CA2244504A1 - Methyl methacrylic resin composition, molded article comprising the same and production of the molded article - Google Patents
Methyl methacrylic resin composition, molded article comprising the same and production of the molded article Download PDFInfo
- Publication number
- CA2244504A1 CA2244504A1 CA002244504A CA2244504A CA2244504A1 CA 2244504 A1 CA2244504 A1 CA 2244504A1 CA 002244504 A CA002244504 A CA 002244504A CA 2244504 A CA2244504 A CA 2244504A CA 2244504 A1 CA2244504 A1 CA 2244504A1
- Authority
- CA
- Canada
- Prior art keywords
- weight
- unsaturated monomer
- resin particles
- resin composition
- parts
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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- 239000000203 mixture Substances 0.000 title claims abstract description 67
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 title claims abstract description 32
- 239000000113 methacrylic resin Substances 0.000 title claims abstract description 30
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 239000000178 monomer Substances 0.000 claims abstract description 85
- 239000011347 resin Substances 0.000 claims abstract description 84
- 229920005989 resin Polymers 0.000 claims abstract description 84
- 239000002245 particle Substances 0.000 claims abstract description 74
- 239000011342 resin composition Substances 0.000 claims abstract description 41
- 229920000642 polymer Polymers 0.000 claims abstract description 19
- 230000000694 effects Effects 0.000 claims abstract description 15
- 238000010526 radical polymerization reaction Methods 0.000 claims abstract description 15
- 239000007870 radical polymerization initiator Substances 0.000 claims abstract description 11
- 239000000463 material Substances 0.000 claims description 53
- 238000000465 moulding Methods 0.000 claims description 27
- -1 methacryloxy groups Chemical group 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 23
- 230000032683 aging Effects 0.000 claims description 13
- 238000002156 mixing Methods 0.000 claims description 12
- 230000000379 polymerizing effect Effects 0.000 claims description 12
- 239000003505 polymerization initiator Substances 0.000 claims description 11
- 238000001746 injection moulding Methods 0.000 claims description 7
- ULQMPOIOSDXIGC-UHFFFAOYSA-N [2,2-dimethyl-3-(2-methylprop-2-enoyloxy)propyl] 2-methylprop-2-enoate Chemical compound CC(=C)C(=O)OCC(C)(C)COC(=O)C(C)=C ULQMPOIOSDXIGC-UHFFFAOYSA-N 0.000 claims description 5
- 239000006096 absorbing agent Substances 0.000 claims description 3
- 238000000748 compression moulding Methods 0.000 claims description 3
- 230000007704 transition Effects 0.000 claims description 2
- 239000002928 artificial marble Substances 0.000 abstract 1
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 46
- 238000004321 preservation Methods 0.000 description 15
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 14
- 238000006116 polymerization reaction Methods 0.000 description 13
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 10
- 238000001723 curing Methods 0.000 description 10
- 230000007547 defect Effects 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 9
- 230000006835 compression Effects 0.000 description 9
- 238000007906 compression Methods 0.000 description 9
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 9
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 8
- 239000004927 clay Substances 0.000 description 8
- 150000002148 esters Chemical class 0.000 description 6
- 239000011521 glass Substances 0.000 description 6
- 150000002500 ions Chemical class 0.000 description 6
- 238000001721 transfer moulding Methods 0.000 description 6
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 5
- 239000003999 initiator Substances 0.000 description 5
- 230000002335 preservative effect Effects 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- PUPZLCDOIYMWBV-UHFFFAOYSA-N (+/-)-1,3-Butanediol Chemical compound CC(O)CCO PUPZLCDOIYMWBV-UHFFFAOYSA-N 0.000 description 4
- MYRTYDVEIRVNKP-UHFFFAOYSA-N 1,2-Divinylbenzene Chemical compound C=CC1=CC=CC=C1C=C MYRTYDVEIRVNKP-UHFFFAOYSA-N 0.000 description 4
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
- 229920001577 copolymer Polymers 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- 238000004898 kneading Methods 0.000 description 4
- SLCVBVWXLSEKPL-UHFFFAOYSA-N neopentyl glycol Chemical compound OCC(C)(C)CO SLCVBVWXLSEKPL-UHFFFAOYSA-N 0.000 description 4
- 150000003254 radicals Chemical class 0.000 description 4
- 239000002994 raw material Substances 0.000 description 4
- 239000002002 slurry Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- KDGNCLDCOVTOCS-UHFFFAOYSA-N (2-methylpropan-2-yl)oxy propan-2-yl carbonate Chemical compound CC(C)OC(=O)OOC(C)(C)C KDGNCLDCOVTOCS-UHFFFAOYSA-N 0.000 description 3
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 3
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 3
- 238000004040 coloring Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- LSXWFXONGKSEMY-UHFFFAOYSA-N di-tert-butyl peroxide Chemical compound CC(C)(C)OOC(C)(C)C LSXWFXONGKSEMY-UHFFFAOYSA-N 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 229940059574 pentaerithrityl Drugs 0.000 description 3
- WXZMFSXDPGVJKK-UHFFFAOYSA-N pentaerythritol Chemical compound OCC(CO)(CO)CO WXZMFSXDPGVJKK-UHFFFAOYSA-N 0.000 description 3
- 229920000573 polyethylene Polymers 0.000 description 3
- 239000006188 syrup Substances 0.000 description 3
- 235000020357 syrup Nutrition 0.000 description 3
- 229940058015 1,3-butylene glycol Drugs 0.000 description 2
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 2
- OZAIFHULBGXAKX-UHFFFAOYSA-N 2-(2-cyanopropan-2-yldiazenyl)-2-methylpropanenitrile Chemical compound N#CC(C)(C)N=NC(C)(C)C#N OZAIFHULBGXAKX-UHFFFAOYSA-N 0.000 description 2
- IYMZEPRSPLASMS-UHFFFAOYSA-N 3-phenylpyrrole-2,5-dione Chemical compound O=C1NC(=O)C(C=2C=CC=CC=2)=C1 IYMZEPRSPLASMS-UHFFFAOYSA-N 0.000 description 2
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 2
- BAPJBEWLBFYGME-UHFFFAOYSA-N Methyl acrylate Chemical compound COC(=O)C=C BAPJBEWLBFYGME-UHFFFAOYSA-N 0.000 description 2
- GYCMBHHDWRMZGG-UHFFFAOYSA-N Methylacrylonitrile Chemical compound CC(=C)C#N GYCMBHHDWRMZGG-UHFFFAOYSA-N 0.000 description 2
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 2
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 2
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 2
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 239000003963 antioxidant agent Substances 0.000 description 2
- 230000003078 antioxidant effect Effects 0.000 description 2
- 235000019437 butane-1,3-diol Nutrition 0.000 description 2
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 239000012986 chain transfer agent Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000004035 construction material Substances 0.000 description 2
- 229920006037 cross link polymer Polymers 0.000 description 2
- 239000003431 cross linking reagent Substances 0.000 description 2
- 125000000113 cyclohexyl group Chemical group [H]C1([H])C([H])([H])C([H])([H])C([H])(*)C([H])([H])C1([H])[H] 0.000 description 2
- 125000003438 dodecyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 2
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 2
- STVZJERGLQHEKB-UHFFFAOYSA-N ethylene glycol dimethacrylate Chemical compound CC(=C)C(=O)OCCOC(=O)C(C)=C STVZJERGLQHEKB-UHFFFAOYSA-N 0.000 description 2
- 239000003063 flame retardant Substances 0.000 description 2
- 230000002431 foraging effect Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- XXMIOPMDWAUFGU-UHFFFAOYSA-N hexane-1,6-diol Chemical compound OCCCCCCO XXMIOPMDWAUFGU-UHFFFAOYSA-N 0.000 description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 2
- 125000002768 hydroxyalkyl group Chemical group 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- FPYJFEHAWHCUMM-UHFFFAOYSA-N maleic anhydride Chemical compound O=C1OC(=O)C=C1 FPYJFEHAWHCUMM-UHFFFAOYSA-N 0.000 description 2
- 150000002825 nitriles Chemical class 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 239000000049 pigment Substances 0.000 description 2
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 2
- 239000004926 polymethyl methacrylate Substances 0.000 description 2
- 229920001451 polypropylene glycol Polymers 0.000 description 2
- FBCQUCJYYPMKRO-UHFFFAOYSA-N prop-2-enyl 2-methylprop-2-enoate Chemical compound CC(=C)C(=O)OCC=C FBCQUCJYYPMKRO-UHFFFAOYSA-N 0.000 description 2
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 238000006748 scratching Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 125000000999 tert-butyl group Chemical group [H]C([H])([H])C(*)(C([H])([H])[H])C([H])([H])[H] 0.000 description 2
- 229920001187 thermosetting polymer Polymers 0.000 description 2
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 description 2
- DTGKSKDOIYIVQL-WEDXCCLWSA-N (+)-borneol Chemical group C1C[C@@]2(C)[C@@H](O)C[C@@H]1C2(C)C DTGKSKDOIYIVQL-WEDXCCLWSA-N 0.000 description 1
- AYMDJPGTQFHDSA-UHFFFAOYSA-N 1-(2-ethenoxyethoxy)-2-ethoxyethane Chemical compound CCOCCOCCOC=C AYMDJPGTQFHDSA-UHFFFAOYSA-N 0.000 description 1
- FXNDIJDIPNCZQJ-UHFFFAOYSA-N 2,4,4-trimethylpent-1-ene Chemical compound CC(=C)CC(C)(C)C FXNDIJDIPNCZQJ-UHFFFAOYSA-N 0.000 description 1
- AVTLBBWTUPQRAY-UHFFFAOYSA-N 2-(2-cyanobutan-2-yldiazenyl)-2-methylbutanenitrile Chemical compound CCC(C)(C#N)N=NC(C)(CC)C#N AVTLBBWTUPQRAY-UHFFFAOYSA-N 0.000 description 1
- PGYMOOZJFWIARO-UHFFFAOYSA-N 2-[(1-carboxy-1-hydroxypropyl)diazenyl]-2-hydroxybutanoic acid Chemical compound CCC(C(=O)O)(N=NC(CC)(C(=O)O)O)O PGYMOOZJFWIARO-UHFFFAOYSA-N 0.000 description 1
- WROUWQQRXUBECT-UHFFFAOYSA-N 2-ethylacrylic acid Chemical compound CCC(=C)C(O)=O WROUWQQRXUBECT-UHFFFAOYSA-N 0.000 description 1
- IFXDUNDBQDXPQZ-UHFFFAOYSA-N 2-methylbutan-2-yl 2-ethylhexaneperoxoate Chemical compound CCCCC(CC)C(=O)OOC(C)(C)CC IFXDUNDBQDXPQZ-UHFFFAOYSA-N 0.000 description 1
- BIISIZOQPWZPPS-UHFFFAOYSA-N 2-tert-butylperoxypropan-2-ylbenzene Chemical compound CC(C)(C)OOC(C)(C)C1=CC=CC=C1 BIISIZOQPWZPPS-UHFFFAOYSA-N 0.000 description 1
- UJTRCPVECIHPBG-UHFFFAOYSA-N 3-cyclohexylpyrrole-2,5-dione Chemical compound O=C1NC(=O)C(C2CCCCC2)=C1 UJTRCPVECIHPBG-UHFFFAOYSA-N 0.000 description 1
- 239000004342 Benzoyl peroxide Substances 0.000 description 1
- OMPJBNCRMGITSC-UHFFFAOYSA-N Benzoylperoxide Chemical compound C=1C=CC=CC=1C(=O)OOC(=O)C1=CC=CC=C1 OMPJBNCRMGITSC-UHFFFAOYSA-N 0.000 description 1
- GAWIXWVDTYZWAW-UHFFFAOYSA-N C[CH]O Chemical group C[CH]O GAWIXWVDTYZWAW-UHFFFAOYSA-N 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 239000004641 Diallyl-phthalate Substances 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- YIVJZNGAASQVEM-UHFFFAOYSA-N Lauroyl peroxide Chemical compound CCCCCCCCCCCC(=O)OOC(=O)CCCCCCCCCCC YIVJZNGAASQVEM-UHFFFAOYSA-N 0.000 description 1
- JCYZMTMYPZHVBF-UHFFFAOYSA-N Melarsoprol Chemical compound NC1=NC(N)=NC(NC=2C=CC(=CC=2)[As]2SC(CO)CS2)=N1 JCYZMTMYPZHVBF-UHFFFAOYSA-N 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-M Methacrylate Chemical compound CC(=C)C([O-])=O CERQOIWHTDAKMF-UHFFFAOYSA-M 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 102100024306 [F-actin]-monooxygenase MICAL1 Human genes 0.000 description 1
- 125000003647 acryloyl group Chemical group O=C([*])C([H])=C([H])[H] 0.000 description 1
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 125000000217 alkyl group Chemical group 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 235000019400 benzoyl peroxide Nutrition 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- QUDWYFHPNIMBFC-UHFFFAOYSA-N bis(prop-2-enyl) benzene-1,2-dicarboxylate Chemical compound C=CCOC(=O)C1=CC=CC=C1C(=O)OCC=C QUDWYFHPNIMBFC-UHFFFAOYSA-N 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 238000012674 dispersion polymerization Methods 0.000 description 1
- CIKJANOSDPPCAU-UHFFFAOYSA-N ditert-butyl cyclohexane-1,4-dicarboperoxoate Chemical compound CC(C)(C)OOC(=O)C1CCC(C(=O)OOC(C)(C)C)CC1 CIKJANOSDPPCAU-UHFFFAOYSA-N 0.000 description 1
- GKCPCPKXFGQXGS-UHFFFAOYSA-N ditert-butyldiazene Chemical compound CC(C)(C)N=NC(C)(C)C GKCPCPKXFGQXGS-UHFFFAOYSA-N 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- PYGSKMBEVAICCR-UHFFFAOYSA-N hexa-1,5-diene Chemical group C=CCCC=C PYGSKMBEVAICCR-UHFFFAOYSA-N 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- MTNDZQHUAFNZQY-UHFFFAOYSA-N imidazoline Chemical compound C1CN=CN1 MTNDZQHUAFNZQY-UHFFFAOYSA-N 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- KQNPFQTWMSNSAP-UHFFFAOYSA-M isobutyrate Chemical compound CC(C)C([O-])=O KQNPFQTWMSNSAP-UHFFFAOYSA-M 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 239000002932 luster Substances 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 229910001507 metal halide Inorganic materials 0.000 description 1
- 150000005309 metal halides Chemical class 0.000 description 1
- QYZFTMMPKCOTAN-UHFFFAOYSA-N n-[2-(2-hydroxyethylamino)ethyl]-2-[[1-[2-(2-hydroxyethylamino)ethylamino]-2-methyl-1-oxopropan-2-yl]diazenyl]-2-methylpropanamide Chemical compound OCCNCCNC(=O)C(C)(C)N=NC(C)(C)C(=O)NCCNCCO QYZFTMMPKCOTAN-UHFFFAOYSA-N 0.000 description 1
- CYTJMBLSQUBVMS-UHFFFAOYSA-N n-[[2-cyanopropan-2-yl(formyl)amino]hydrazinylidene]formamide Chemical compound N#CC(C)(C)N(C=O)NN=NC=O CYTJMBLSQUBVMS-UHFFFAOYSA-N 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 125000000864 peroxy group Chemical group O(O*)* 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 239000001294 propane Substances 0.000 description 1
- 230000002393 scratching effect Effects 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- MWNQXXOSWHCCOZ-UHFFFAOYSA-L sodium;oxido carbonate Chemical compound [Na+].[O-]OC([O-])=O MWNQXXOSWHCCOZ-UHFFFAOYSA-L 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000010557 suspension polymerization reaction Methods 0.000 description 1
- SWAXTRYEYUTSAP-UHFFFAOYSA-N tert-butyl ethaneperoxoate Chemical compound CC(=O)OOC(C)(C)C SWAXTRYEYUTSAP-UHFFFAOYSA-N 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L33/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
- C08L33/04—Homopolymers or copolymers of esters
- C08L33/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, which oxygen atoms are present only as part of the carboxyl radical
- C08L33/10—Homopolymers or copolymers of methacrylic acid esters
- C08L33/12—Homopolymers or copolymers of methyl methacrylate
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2/00—Processes of polymerisation
- C08F2/46—Polymerisation initiated by wave energy or particle radiation
- C08F2/48—Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light
- C08F2/50—Polymerisation initiated by wave energy or particle radiation by ultraviolet or visible light with sensitising agents
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F220/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride ester, amide, imide or nitrile thereof
- C08F220/02—Monocarboxylic acids having less than ten carbon atoms; Derivatives thereof
- C08F220/10—Esters
- C08F220/12—Esters of monohydric alcohols or phenols
- C08F220/14—Methyl esters, e.g. methyl (meth)acrylate
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F265/00—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00
- C08F265/04—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00 on to polymers of esters
- C08F265/06—Polymerisation of acrylate or methacrylate esters on to polymers thereof
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0065—Manufacturing aspects; Material aspects
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Abstract
A methyl methacrylic resin composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles and (C) 0.1 to 5 % by weight of a radical polymerization initiator, is provided. The resin composition has an excellent handling property, generates little odor, and can be easily molded to obtain artificial marble. The methyl methacrylic resin composition gives a molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistance. The molded article may be preferably used as a lamp cover.
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles and (C) 0.1 to 5 % by weight of a radical polymerization initiator, is provided. The resin composition has an excellent handling property, generates little odor, and can be easily molded to obtain artificial marble. The methyl methacrylic resin composition gives a molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistance. The molded article may be preferably used as a lamp cover.
Description
CA 02244~04 1998-08-06 M~THYL METHACRYLIC RESIN COMPOSITION, MOLDED ARTICLE
COMPRISING THE SAME AND PRODUCTION OF THE MOLDED ARTICLE
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a methyl methacrylic resin composition, a molded article comprising the composition and a method of producing the molded article.
BAC~GROUND OF TH~ INVENTION
Methyl methacrylic resins containing methyl methacrylate as a main component have found applications in variety of fields such as lighting apparatuses, parts for automobiles, billboards and construction materials, sincethe resin is advantageous in regardstotransparency, luster on the surface and the like.
The methyl methacrylic resins are not always sufficient in view of scratch-resistance and hardness of the surface. To improve the scratch-resistance, a variety of methods such as a metnod of applying or laminating a hard-coat layer to the resin surface, has been conducted to prevent scratching. However, these methods consist of many steps before obtainingthe products and, are therefore unnecessarily costly for industrial production.
On the otner hand, methods wherein methyl methacrylic resin compositions are obtained by cross-linking the resin CA 02244~04 1998-08-06 itself have been proposed for improving the scratch-resistance of the molded article thereof.
For example, the Japanese Patent Laid-Open No. 6-62380-B (corresponding to the United States Patent No.
4,698,373) discloses prosthetic teeth (i) made of a hardened polymer made of composition containing a blend of (a) from 0 % to about 50 % by weight of an uncross-linked polymer solution, (b) from about 2 % to about 30 % by weight of a polymerizable monomer, (c) from about 10 % to about 70 % of a cross-linked polymer in the form of discrete particles having average diameters from about 0.001 micron to about 500 microns and being swollen in said solution and (d) from 20 % to about 70 % of a cross-linking agent fcr said monomer, provided that when the component (d) is of from 20 % to 27 %, the component (b) is of 20 % or less and that the above percentages are based on the total weight of components (a), (b), (c) and (d) in said composition;
(ii) possessing a superior chemical resistance against methyl methacrylate; and (iii) having a grind-resistance value from 450 to 550 g/sec. It discloses a use of the above-mentionedmethylmethacrylicresincompositionwhich somewhat improves the scratch-resistance thereof. The resin composition is used for prosthetic .eeth which are made of a stable one part dental prosthesis composition 26 employing an IP~ technology.
CA 02244~04 1998-08-06 Additionally, various methods for obtaining alkyl methacrylic resin compositions such as methyl methacrylic resin compositions have been proposed.
For example, the Japanese Patent Application Laid-Open No. 62-2201-A discloses a methyl methacrylic resin compositionobtainedbycross-linkingtheresinitselfsuch that the resin composition is obtained by polymerizing a mixture which comprises (a) resin raw materials selected from an alkyl methacrylate monomer, an ~,~-ethylenic unsaturated monomer mixture containing mainly alkyl methacrylates, and a syrup containing a polymer thereof, and (b) 12 to 40 parts by weight of a cross-linking agent based on 100 parts by weisht of the resin raw materials.
It discloses the resin composition is used for production of a lens for lamp having a thermal deformation temperature of 130 ~C or more.
The Japanese Patent Application Laid-Open No. 62-79206-A discloses another methyl methacrylic resin compositionobtainedbycross-linkingtheresinitself,and discloses that methacrylic resin moldings are produced by moldingpartially-crosslinkedgel-likepo'ymerpreparedby polymerizing partially mixtures of 100 parts by weight of (a)resin raw materials selected from an alkyl methacrylate monomer, an ~,~-ethylenic unsaturated monomer mixture containing mainly alkyl methacrylates, and a syrup CA 02244~04 1998-08-06 containing a polymer thereof, and (b) 2 to 250 parts by weight of across-linking agentbased on 100partsby weight of the resin raw materials, wherein the total amounts of the polymers contained in crosslinked polymers are not more than 80 weight % and they are 4 to 65 weight % more than the amounts of the polymers contained in the said mixture of (a) and (D), by a injection molding method, aco~pression molding method or a transition molding method.
The Japanese Patent Application ~aid-Open No. 7-70236-A also discloses another methyl methacrylic resin compositionobtainedbycross-linkingtheresinitself,and discloses thermosetting resin compositions containing (i) partially crosslinked gel-like polymers prepared by polymerising (a) monomers containing mainly alkyl methacrylates or syrups thereof and (b) at least two (meth)acryloyl groups-containing compounds and (ii) peroxides containing mainly peroxy-ketals having exothermic peak temperature of at least 110~C and below 130~C in amount of 0.05-0.2 ~ in terms or active oxygen.
However, in the Japanese Patent Application Laid-Open No. 6-62380-A, the objects of the invention are that the methylmethacrylicresincompositionisusedforprosthetic dental appli~nces such as prosthetic teeth and, therefore, it is suggested that the component is used with pigments and fillers to improve the appearance, the density and the CA 02244~04 1998-08-06 physical properties of the desirable prosthetic teeth, and is not neededthat the article made ofthe resincomposition has high transparency.
In all of the Japanese Patent Application Laid-Open Nos~ 62-2201-A, 62-79206-A and 7-70236-A, the method of partially polymerizing the methyl methacrylic resin components in the composition are carried out. In such a method, the reaction conditions such as temperature and time have to be elaborately controlled since the content 0 of the polymer is likeiy to vary widely and this amount of scattering in the content may cause trou~les when the composition are molded. Additionally, even once the polymerization reaction is terminated, the reaction might ~e started again by the remaining polymerization initiator resulting in an unintended composition when the resin composition is transported or is stocked as lt is. Specia~
apparatuses or facilities such as an apparatus for keeping cold are needed since a preservative property is not enough and, therefore, the method is disadvantageous, industrially.
SUMMARY AND OBJECTS OF TH~ lNV~N'l'ION
The present inventor has intensively investigated regarding a methyl methacrylic resin composition having little amount of scattering in the content and an excellent CA 02244~04 1998-08-06 preservative property and being capable of giving a molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistance. As a result, ithasbeenfoundthataspecific methyl methacrylic 6 resin composition comprising the components of (A) a certainamountofanunsaturatedmonomermixturecomprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (3) a certain amount of resin particles made of a polymer of a specific methyl methacrylic unsaturated monomer, and (C) a certain amount of a radical polymerization initiator, has little amount of scattering in the content and an excellent preservative property, and is able to give a molded article whichhasa~ightransparency,ahighhardnessofthesurface 16 and an excellent scratch-resistance.
Thus, the present invention provides a methyl methacrylic resin composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymeri7ation, (B) 40 to 70 ~ by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linkedresinparticlesand(ii)Oto80partsbyweight ofuncross-linkedresinparticles,whereinthetotalamount CA 02244~04 1998-08-06 of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each OI components ~A), (B) and (C) is based on the total amount of components (A~ and (B).
The present invention further provides a molded article, especially a lamp cover, obtained by polymerizing and curing said methyl m.ethacrylic resin composition.
The present invention still further provides a method for producing a molded article, comprising the steps of mixing components (A), (B) and (C) to obtain a material for molding, and heating and curing the material for molding.
1~
DETAILED DESCRIPTION OF THE INVENTION
The methyl methacrylic resin composition of the present invention comprises the components of:
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can erfect radical polymeri~ation, (~) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially c-oss-linkedresinparticlesand(ii)Oto80partsbyweight CA 02244~04 1998-08-06 ofuncross-linkedresinparticles,whereinthetotalamount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weisht of a radical polymerization initiator, wherein the amount of each of components (A), (B) and (C) is based on the iotal amount of components (A) and (B).
~he ursaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, which is used as component (A) in the present invention, is preferably a mixtureofanunsaturatedmonomerhavingat leasttwodouble bonds which can effect radical polymerization and an 16 unsaturated monomer copolymeri~able with s~id unsaturated monomer. Hereinafter, the unsaturated monomer having at least two double bonds which can effect radical polymerization is called "a polyfunctional unsaturated monomer", andtheunsaturated monomer copolvmerizable with the polyfunctional unsaturated monomer is called "a monofunctional unsaturated monomer". lhe unsaturated monomer mixture preferably contains about 50 % by weight or more, more preferably about 55 % by weight or more, of said polyfunctional unsaturated monomer.
Examples of the polyfunctional unsaturated monomer CA 02244~04 1998-08-06 include allyl methacrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,3-butylene glycol di~meth)acrylate, 1,6-hexane diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, divinylbenzene, diallyl ph~h~late, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethyloimethane tetra(meth)acrylate, and the like. ~ere, the term "(meth)acrylate"representsbothacrylateandmethacrylate, and hereinafter, the term "(meth)" has an analogous meaning indicating the optional presence of a methyl substituent.
Among them, a polyfunctional unsaturated monomer having at least two methacryloxy groups as a double bond which can effect radical polymerization is preferred since the polyfunctional unsaturated monomer reacts readily with an unsaturated monomer copolymerizable with said polyfunctional unsaturated monomer and, thererore, there remains only a little amount of unsaturated monomer which hasnotreactedinthecuringreactionthereof. Amongthese, neopentyl glycol dimethacrylate is one of the most preferred examples. The polyfunctional unsaturated monomer can be used independently or in ~ombination of two or more.
CA 02244~04 1998-08-06 In the present invention, the monofunctional unsaturated monomer can be used with the polyfunctional unsaturated monomer and is not restricted as long as it has the copolymerizable property, and can be appropriately selected for use. Example of the monofunctional unsaturated monomer include esters of methacrylic acid or acrylicacidwithaliphatic,aromaticoralicyclicalcohols, such as methyl (meth)acrylate, ethyl ~meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, ~-ethylhexyl (meth)acrylate, lauryl ~meth)acrylate, tetrahydrofurfuryl (meth)acryiate, isoborny' (meth)acrylate, benzyl (meth)acrylate and cyclohexyl (meth)acrylate; (meth)acryl-based monomers such as hydroxyalkyl esters such 2S hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate; unsaturated acids such as acrylic acid ard methacrylic acid; styrene-based monomers such as styrene and ~-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; and monofunctional unsaturated monomers such as maleic anhydride, phenylmaleimide, cvclohexylmaleimide and vinyl acetate.
Among them, esters of methacrylic acid are preferred.
In the present invention, the above-mentioned monofunctional unsaturated monomer and/or polyfunctional unsaturated monomer can also be used with dissolving a CA 02244~04 1998-08-06 homo-polyme_ thereof and/or co-polymer thereof.
The methyl methacrylic resin composition of the present invention comprises about from 30 to about 60 % by weight, preferably about from 40 to about 55 % by weight, of the unsaturated monomer mixture component (A) based on the total amount of components (A) and (B). When the content of the unsaturated monomer mixture component (A) is less than bout 30 % by weignt, sufficient moldability is not obtained in molding the resin composition. On tne other hand, when the content is over about 60 % by weight, stickinessofamaterialtobemoldedwhichisobtainedafter kneading the resin composition is high and it is difficult to keep the form after kneading and, therefore, handling inbothcases is not good, undesirably. In additiontothat, whenthecontentisoverabout60%byweiaht,iticdifficult to obtain a molded article having a flat surface, undesirably, since a shrinkage of the molded article due to the polymerization becomes large.
The methyl methacrylic resin composition of the present invention comprises from about 40 to about 70 % by weight ofresinparticles ofcomponent (B) made of apolymer of a methyl methacrylic unsaturated monomer, based on the total amount of components (A) and (B), which comprise (i) partially cross-linked resin particles and (ii) uncross-linked resin particles. The resin particles of CA 02244~04 1998-08-06 component (B) made of a polymer of a methyl methacrylic unsaturated monomer are made from a copolymer comprising a methyl methacrylate monomer and an unsaturated monomer copolymerizable with methyl methacrylate, or the copolymer 6 and a homopolymer of methyl methacrylate, and the resin particles are preferably made from about ~0 ~ by weight or more, morepreferably about80%byweightormore,ofmethyl methacrylate based on the resin particles.
Examples of the unsaturated monomer copolymerizable with methyl methacrylate include the same monofunctional unsaturated monomers and the same polyfunctional unsaturated monomers as mentioned above.
Specific examples of the polyfunctional unsaturated monomers which are used as the unsaturated monomer copolymerizable with methyl methacrylate include, but are not limited to, allyl methacrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethvlene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,6-hexane diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, divinylbenzene, diallyl phthalate, trimethylolpropane tri(meth)acryl te, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane 2~ tetra(meth)acrylate, and the like.
CA 02244~04 1998-08-06 Specific examples of the monofunctional unsaturated monomer include, but are not limited to, esters of methacrylic acid or acrylic acid with aliphatic, aromatic or alicyclic alcohols, such as methyl acrylate, ethyl 5 (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, ben2yl (meth)acrylate and cyclohexyl (meth)acrylate; (meth)acryl-based monomers such as hydroxyalkyl esters such as hydroxye~hyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate; unsaturated acids such as acrylic acid and methacrylic acid; styrene-based monomers such as styrene and ~-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; and monofunctional unsaturated monomers such as maleic anhydride, phenylmaleimide, cyclohexylmaleimide and vinyl acetate.
When component (B) is made, the unsaturated monomer 2~ of which component (B) is composed can be used with dissolving a homo-poiymer thereof and/or co-polymer thereof in the same way as mentioned regarding component (A).
The resin particles used as component (B) in the present invention are, fcr example, resin particles CA 02244~04 l998-08-06 obtainedbypolymerizationsuchasemulsionpolymerization, suspension polymerization and dispersion polymerization, and resin particles obtained by grinding a resin polymer, which is obtained by other polymerization, into pieces.
An average particle size of the resin particles, especially that ofpartially cross-linkedresinparticles~
is usually in the range of about i to about 100 ~ m. The size can be controlled by conducting a suitable polymerizationmethodwhichismentionedabove. Whenresin particles having a particle size less than about 1 ~ m are used, it tends to be difficult tO mix or knead the -esin particleswiththeunsaturatedmonomermixtureofcomponent (A). On the other hand, when resin particles having a particle size over about 100 ~ m are used, the form of the particles tends to be noticeable after molding.
The resin particles of component (B) comprise (i) from about 20 to about 100 parts by weight of partially cross-linked resin particles and (ii) from 0 to about 80 parts by weight Gf uncross-linkea resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight. When the ratio of the partially cross-linked resin particles accounts for less than about 20partsbyweightinthetotalamountoftheresinparticles 2a addins up to 100 parts by weight, the stickiness of the CA 02244~04 1998-08-06 composition is high, and the handling property deteriorates.
The ratio of the partially cross-linked resin particles accounting for about 20 to about 100 % by weight a of component (B) and the ratio of the uncross-linked resin particles accounting for 0 to about 80 % by weight of component (B), eachbeing based onthe total amount of these resin particles, can be appropriately selected depending on the use of the molded article to be obtained, provided that these -atios falls in the each above-mentioned range.
~mong these, the ratio of the partia1ly cross-linked resin particles is preferabiy from about 50 to about 100 % by weight.
The partially cross-linked resin particles in the la present invention swell and are not completely dissolved in solvents in which polymethylmethacrylate can be dissolved, such as acetone.
The partially cross-linked resin particles can be obtained, for example, by adding the polyfunctional unsaturated monomer when a mixture of about ~C % by weight or more of methylmethacrylate and an unsaturated monomer copolymeriza~le with methylmethacrylate is polymerized to obtain resin particles thereof or of a polymer thereof.
The resin particles of component (B) are contained in the present resin composition in an amount of about 40 to CA 02244~04 1998-08-06 about 70 % by weight, preferably about 45 to about 60 % by weight, based on the total amount of compounds (A) and (B).
Whenthe amountislesstnanabout40~byweight,stickiness of a material to be molded which is obtained after kneading a the resin composition is high and it is difficult to keep theformafterkneadingand,therefore,handlingisnotgood, undesirably. On the other hand, when the amount is more than about 70 % by weight, it is difficult to uniformly mix or knead the resin composition, undesir~Dly.
The resinparticlesc2noption211ycont2inagentssuch as an antioxidant, an ultraviolet-ray absorbing agent, a chain transfer agent, a releasing agent, a flame retardant and a dye, and these agents can be used in the resin composition of the present invention.
1~ A radical polymerization initiator is used as component (C) in the resin composition of the present composition, and it effects polymerization and curing of the unsaturated monomer mixture component (A).
Examples of the radical polymerization initiator include azo compounds such as 1,1'-a70bis(cycloh2xane-l-carbonitrile), 2,2'-azobis(2,4,4-trimethylpentene), 2,2'-azobis(2-methylpropane), 2-cyano-2-propylazoformamide, 2,2'-azobis(2-hydroxy-methylpropionate), 2,2'-azobis(2-methyl-butyronitrile), 2a 2,2'-azobisisobutyronitrile, 2~2~-azobis[2-(2-CA 02244~04 l998-08-06 imidazolin-~-yl)propane] and dimethyl-2,2~-azobis(2-methylpropionate); diacyl and/or dialkyl peroxide-based initiatorssuchasdicumylperoxide,t-butylcumylperoxide, di-t-butyl peroxide, benzoyl peroxide and lauroyl peroxide; peroxy ester-based initiators such as t-butyl peroxy-3,3,5-trimethylhexanoate,t-butylperoxyllaurate, t-butyl peroxy isobutyrate, t-butyl peroxy acetate, di-t-butyl peroxyhexahydro terephthalate, di-t-butyl peroxy a7elate, t-butyl peroxy-~-ethyl hexanoate~ 1,1,3,3-tetramethylbutyl peroxy-2-ethyl nexanoate and t-amyl peroxy-2-ethyl hexanoate; percarbonate-based initiators such as t-butyl peroxy allyl carbon-te and t-butyl peroxyisopropyl carbonate; and peroxy ~etal-based initiators such as l,l-di-t-butyl peroxycyclohexane, la l,l-di-t-butyl peroxy-3,3,5-trimethylcyclohexane and l,l-di-t-hexyl peroxy-3,3,5-trimethylcyclohexane.
These radical polymerlzation initiators can be used independently or in combination of two or more~
When a polymerization initiator which decomposes even at low temperature is used, lt may cause the radical polymerizatior. in mixing the resin composition or in storage after the mixing and, therefore, a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is about 60 ~C o_ higher is ~a preferablyusedinthepresentinvention. Ontheotherhand, CA 02244~04 1998-08-06 a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is over about 100 ~C is not industrially preferable, since it needs high temperature or much time for a curing reaction a of the unsaturated monomer mixture component (A) which is described later in detail. Therefore, a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is in the r~nge of about 60 to about 100 ~C is preferably used, and by using sucr. a polymerization initiator, both an excellent preservative property of the resin composition, and desirable temperature andtimeforthecuringreactioncanbeachieved at the same time.
~he radical polymerization initiator component (C) is contained in the present resin composition in an amount of about 0.1 to about 5 % by weight, preferably about 0.1 to about 2 % by weight, based on the total amount of components (A) and (B). When the amount is less than about 0.1 ~ by weight, the radical polymerization reauires long period of time, and when the amount is more than about 5 % by weight, the unsaturated monomer mixture component (A) can not be polymerized steadily.
The resin composition of the present invention can further contain a releasing agent, an ultraviolet-ray 2~ absorbing agent, a dye, a pigment, a polymerization CA 02244~04 1998-08-06 inhibitor, a chain transfer agent, an antioxidant, a flame retardant, a reirforcing agent and the like. For example, an ultraviolet-ray a~sorbing agent can be contained in the methyl methacrylic resin composition of the present 5 invention in amount of about 10 to about 1000 ppm based on the total amount of components (A), (B) and (C).
The p-esent inventiGn also provides a method for producing a molded article using the methyl methacrylic resin composition.
The method for producing the molded article comprises steps of (i) mixing and aging the methyl methacrylic resin compositionof'hepresentinvention,and(ii)polymerizing and curing the resulting composition.
In the step of the mixing and aging the methyl methacrylic resin composition, components (A), (B) and (C) are mixed to obtain a final uniform resin composition.
Specific examples of the step include a step such that components (A), (B) and (C) zre mixed to obtzin a slurry of the resin composition, tAen the slurry is aged in an appropriate vessel.
A shape of the vessel is not particularly restricted.
Examples of the vessel include a cell composed OI at least two flat plates facing each other and a sealing material.
A material of the vessel ia not particularly restricted, 2~ provided that it is not dissolved in or is not corroded by CA 02244~04 1998-08-06 component (A) or (C).
Theresincompositionmixedmaybeenclosedinavessel, and heated for aging. During the aging, the unsaturated monomer mixture component (A) may be impregnated into the 6 resin particles component (B) and the uncross-linked resin pzrticles in the component (B), when it is used, may be dissolvedintheunsaturatedmonomermixturecomponent(A).
An appearance of the resin composition usually changes from a slurry form to a clay form during the aging, and the resin composition after tr.e aging, which is a so~t m~terial, can be used as a material to be molded.
The aging temperature preferably falls in the range of about 20 ~C to about 80~C. When the mixed resin composition is heated over about 80~C, undesirable polymerization and curing reaction may occur due to the added radical polymerization initiator. When the mixed resin composition is aged at a temperature lower than about 20~C, the aging requires ar. undesirable length of time.
The aging conditions, except the temperature, are chosen according tc the resin composition, especially to the kind of the resin particles component (B), the composition of the unsaturated monomer mixture component (A), the kind OI the radical polymerization initiator component (C) and the like.
26 For example, the mixing and the heating of the resin CA 02244~04 l998-08-06 composition can be conducted at the same time by selecting an appropriate temperature when the mixing and the aging of the resin composition are carried out. At that time, a known kneading apparatus such as a 2-axis extruder, an 6 almighty mixing apparatus, a kneader and a banbury mixer can be used as a ~neading apparatus.
Afterthemixingandagingstep,amaterialtobemolded is obtained. Thls materiai is soft and, therefore, has excellent handling property. The material can be easily processed and desirably shaped. For example, the material can be handled ln var-ous forms such as sheet, block, cake, rod, pellet, ribbon and slrand.
That is, after the mixing and aging step, polymerizing and curing steps are conducted, and the above-mentioned la material to be molded may be thrown into a mold of various shapes, pressed, heated, shaped and cured to obtain molded articles of various forms.
When a curing reaction by a radical polymerization reaction is conducted in the present inventionr a reaction temperature from about 80 to about 160 ~C is preferable.
When the temperature is lower than about 80 ~C, the curing reaction requires a long period of time and is industrially disadvantageous. On the other hand, when the temperature isoverabout160 ~C,decompositionandcolorationmayoccur, 2~ undesirably.
CA 02244~04 1998-08-06 Any method of molding can be used as long as the material to be molded is pressed, heated, shaped and cured.
Examples thereofinclude press molding, injection molding, transfer molding and the like.
When press molding is carried out, a press molding apparatus comprising a pressure-applying unit and a mold may be used. Temperature of a mold in press molding is preferablycontrolledtobeintherangeofzbout 80toabout 160 ~C.
The mold-surtace of the outer and inner molds may or may not have the same temperature provided the difference between outer mold surfacs and inner mold surface does not exceed about 20 ~C.
A mold compression pressure is usually in the range 1~ of about 20 to about 100 kg/cm2. When the pressure is lower than about 20 kg/cm2, defects such as inner cracks tend to be caused, and surface defects may be caused on the surface of the molded article by boiling of methyl methacrylate contained in the material to be molded. On the other hand, when the pressure is over about 100 ~g/cm2, the material to be molded may flow undesirably out of the mold during compression.
The molding conditions such zs the temperature of the mold, the mold compression pressure, a rate of a mold 2~ compression and a place at which the material to be molded CA 02244~04 1998-08-06 is thrown into the mold are selected depending on the shape of the molded article and tne period of time needed for producing the molded article.
When injection molding or transfer molding is carried out, an injection molding apparatus or a transfer molding apparatus comprising an injection unit and a mold compression unit is used.
A suitable screw used for a measurement or a injection has a pressure ratio of 1.5 or less. The screw may have a bac~-flow-preventing ring, which can be of a various structure, in vicinity of the top.
Temperature of a cylinder covering a screw and cr a pipe for iransfer of transfer molding is preferably controlled at about 60 ~C or less. When the temperature is la over about 60 ~C, a local-temperature increase may take place due to shearing heat generation between the screw and thecylinderorinthepipe duringthetransfer, andacuring reaction of the material may be initiated, undesirably.
When injection molding or transfer molding is carried out,temperatureofthe moldiscontrolledtobeintherange of about 80 to about 160 ~C. The mold-surface of the outer and inner molds may or may not have the same temperature provided the difference between outer mold surface and inner mold surface does not exceed about 20 ~C.
2~ A mold compression pressure and a clearance between CA 02244~04 1998-08-06 molds may be controlled constantly, or may be controlled continuously or gradually depending on the progress of the curing reaction.
The molding conditions of injection molding and transfer molding such as the ~emperatur2 of the mold, the mold compression pressure, a rate of a mold compression and a place at which the material to be molded is added into the mold are also selected depending on the shape of the molded article and the period of time needed for producing the molded article.
~ sdescribedabove,themoldedarticleisthusobtained in the present invention~ The molded article has a high hardnessofthesurfaceandanexcellentscratch-resistance.
The surface hardness thereof can be at least 3H, and is 16 usually 4~ or more of tne pencil hardness. In addition, the molded article has an excellent appearance without any defects such as cracks.
The moldedarticleofthepresent inventioncanbeused in variety of fields. Examples of the fields include automobile-related parts such as a tail-lamp cover, head-lamp cover, a meter panel, various windows and components for mirrors, construction materials such as commonly used windows and boards for room-compartments, coating materials used for, for example, a bath tub or a washstand, kitchenware such as resin tableware, parts for CA 02244~04 1998-08-06 2a appliances concerning running-water such as windows of microwave ovens, protecting front panels used for, for example, a liquid crystal display, other front panels for displays or various kinds of monitors, covers for various machines, lenses such as _resnel lenses, lenses for a watch and lenses for glasses, disk substrates used for, for example, compact disks or digita'-videc àis~s, ccvers for hot-water apparatuses using solar energy, protecting covers for solar batteries and various signboards.
The molded article of the present invention has a high transparency and an excellent weather-resistance as well as a high hardness of the surface and an excellent scratch-resistance and, therefore, may be preferably used inthefieldswhereinpropertiessuchasahightransparency, an excellent weather-resistance and an excellent scratch-resistance are needed. ~specially, the molded article is preferably used as a lamp cover in the various fields such as automobile, shipp-ng, _-rlin2 system, outdoor apparatuses and signals. Specific examples of the usage thereof include materials of covers for lamps such as a tail lamp, a head lamp, a fog lamp, a halogen lzmp, a metal halide lamp, a xenon lamp, a fluorescence mercury lamp and sodium lamp.
~s described above, the present invention provides methyl methacrylic resin compositions whicn have little CA 02244~04 1998-08-06 amount of scattering in the content and an excellent preservative property, and is able to give a molded article whichhasahightransparency,ahighhardnessofthesurface and an excellent scratch-resistance. The material to be molded comprising said methyl methacrylic resin composition is excellent ir.view of a handlins ?roper'y and amoldingproperty, andcangive anexcellent molded article having a gooa appearan.ce. AccQrai ng tO th~ ~resent invention, the molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistarce can be steadily and easily processed. The presert invention may be p_eferably used inthefieldswhereinpropertiessuchasahightransparency, ar. excellent weatr.~r-resistance and an excellent sc~atch-resistance are needed, ror example, in the field of a lamp cover.
The entire disclosure of the Japanese Patent Application No. 5-212942 _iled on August 7, lg97 ard the JapanesePatent Applicat-on No.l0-739l7 filed or March23, 1998, both indicating specification, claims and s~mmary, are incorporated herein by reference in their entirety.
EXAMPLES
The present invention is described in more detail by reference to the following Examples, which should not be CA 02244~04 1998-08-06 construed as a limitation upon the scope of the present invention.
In the Examples, the measurement of physical properties was conducted by the following methods.
(1) Handling property of the m-~ erial to be molded:
A handling propertv of the obtained m2terial to be molded was evaluated by the extent of stickiness thereof, whlch is determined by a method of touching while wearing a polyethylene glov~.
(2) Molding property of the material to be molded:
80 g OI the obtained material to be molded WâS thrown into a plate-form mold of 120 x 120 x 20 mm, and was subjected to thermal compression molding for 10 minutes under conditions of a temperature of 120 ~C and a mold compressionpressure Ot- 7 0 kg/cm2 tO obtaina~oldedarti-le.
Amoldingpropertyo_thematerialtobemoldedwasevaluated bv the appearance OI the obtained mol~ed article.
COMPRISING THE SAME AND PRODUCTION OF THE MOLDED ARTICLE
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a methyl methacrylic resin composition, a molded article comprising the composition and a method of producing the molded article.
BAC~GROUND OF TH~ INVENTION
Methyl methacrylic resins containing methyl methacrylate as a main component have found applications in variety of fields such as lighting apparatuses, parts for automobiles, billboards and construction materials, sincethe resin is advantageous in regardstotransparency, luster on the surface and the like.
The methyl methacrylic resins are not always sufficient in view of scratch-resistance and hardness of the surface. To improve the scratch-resistance, a variety of methods such as a metnod of applying or laminating a hard-coat layer to the resin surface, has been conducted to prevent scratching. However, these methods consist of many steps before obtainingthe products and, are therefore unnecessarily costly for industrial production.
On the otner hand, methods wherein methyl methacrylic resin compositions are obtained by cross-linking the resin CA 02244~04 1998-08-06 itself have been proposed for improving the scratch-resistance of the molded article thereof.
For example, the Japanese Patent Laid-Open No. 6-62380-B (corresponding to the United States Patent No.
4,698,373) discloses prosthetic teeth (i) made of a hardened polymer made of composition containing a blend of (a) from 0 % to about 50 % by weight of an uncross-linked polymer solution, (b) from about 2 % to about 30 % by weight of a polymerizable monomer, (c) from about 10 % to about 70 % of a cross-linked polymer in the form of discrete particles having average diameters from about 0.001 micron to about 500 microns and being swollen in said solution and (d) from 20 % to about 70 % of a cross-linking agent fcr said monomer, provided that when the component (d) is of from 20 % to 27 %, the component (b) is of 20 % or less and that the above percentages are based on the total weight of components (a), (b), (c) and (d) in said composition;
(ii) possessing a superior chemical resistance against methyl methacrylate; and (iii) having a grind-resistance value from 450 to 550 g/sec. It discloses a use of the above-mentionedmethylmethacrylicresincompositionwhich somewhat improves the scratch-resistance thereof. The resin composition is used for prosthetic .eeth which are made of a stable one part dental prosthesis composition 26 employing an IP~ technology.
CA 02244~04 1998-08-06 Additionally, various methods for obtaining alkyl methacrylic resin compositions such as methyl methacrylic resin compositions have been proposed.
For example, the Japanese Patent Application Laid-Open No. 62-2201-A discloses a methyl methacrylic resin compositionobtainedbycross-linkingtheresinitselfsuch that the resin composition is obtained by polymerizing a mixture which comprises (a) resin raw materials selected from an alkyl methacrylate monomer, an ~,~-ethylenic unsaturated monomer mixture containing mainly alkyl methacrylates, and a syrup containing a polymer thereof, and (b) 12 to 40 parts by weight of a cross-linking agent based on 100 parts by weisht of the resin raw materials.
It discloses the resin composition is used for production of a lens for lamp having a thermal deformation temperature of 130 ~C or more.
The Japanese Patent Application Laid-Open No. 62-79206-A discloses another methyl methacrylic resin compositionobtainedbycross-linkingtheresinitself,and discloses that methacrylic resin moldings are produced by moldingpartially-crosslinkedgel-likepo'ymerpreparedby polymerizing partially mixtures of 100 parts by weight of (a)resin raw materials selected from an alkyl methacrylate monomer, an ~,~-ethylenic unsaturated monomer mixture containing mainly alkyl methacrylates, and a syrup CA 02244~04 1998-08-06 containing a polymer thereof, and (b) 2 to 250 parts by weight of across-linking agentbased on 100partsby weight of the resin raw materials, wherein the total amounts of the polymers contained in crosslinked polymers are not more than 80 weight % and they are 4 to 65 weight % more than the amounts of the polymers contained in the said mixture of (a) and (D), by a injection molding method, aco~pression molding method or a transition molding method.
The Japanese Patent Application ~aid-Open No. 7-70236-A also discloses another methyl methacrylic resin compositionobtainedbycross-linkingtheresinitself,and discloses thermosetting resin compositions containing (i) partially crosslinked gel-like polymers prepared by polymerising (a) monomers containing mainly alkyl methacrylates or syrups thereof and (b) at least two (meth)acryloyl groups-containing compounds and (ii) peroxides containing mainly peroxy-ketals having exothermic peak temperature of at least 110~C and below 130~C in amount of 0.05-0.2 ~ in terms or active oxygen.
However, in the Japanese Patent Application Laid-Open No. 6-62380-A, the objects of the invention are that the methylmethacrylicresincompositionisusedforprosthetic dental appli~nces such as prosthetic teeth and, therefore, it is suggested that the component is used with pigments and fillers to improve the appearance, the density and the CA 02244~04 1998-08-06 physical properties of the desirable prosthetic teeth, and is not neededthat the article made ofthe resincomposition has high transparency.
In all of the Japanese Patent Application Laid-Open Nos~ 62-2201-A, 62-79206-A and 7-70236-A, the method of partially polymerizing the methyl methacrylic resin components in the composition are carried out. In such a method, the reaction conditions such as temperature and time have to be elaborately controlled since the content 0 of the polymer is likeiy to vary widely and this amount of scattering in the content may cause trou~les when the composition are molded. Additionally, even once the polymerization reaction is terminated, the reaction might ~e started again by the remaining polymerization initiator resulting in an unintended composition when the resin composition is transported or is stocked as lt is. Specia~
apparatuses or facilities such as an apparatus for keeping cold are needed since a preservative property is not enough and, therefore, the method is disadvantageous, industrially.
SUMMARY AND OBJECTS OF TH~ lNV~N'l'ION
The present inventor has intensively investigated regarding a methyl methacrylic resin composition having little amount of scattering in the content and an excellent CA 02244~04 1998-08-06 preservative property and being capable of giving a molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistance. As a result, ithasbeenfoundthataspecific methyl methacrylic 6 resin composition comprising the components of (A) a certainamountofanunsaturatedmonomermixturecomprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (3) a certain amount of resin particles made of a polymer of a specific methyl methacrylic unsaturated monomer, and (C) a certain amount of a radical polymerization initiator, has little amount of scattering in the content and an excellent preservative property, and is able to give a molded article whichhasa~ightransparency,ahighhardnessofthesurface 16 and an excellent scratch-resistance.
Thus, the present invention provides a methyl methacrylic resin composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymeri7ation, (B) 40 to 70 ~ by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linkedresinparticlesand(ii)Oto80partsbyweight ofuncross-linkedresinparticles,whereinthetotalamount CA 02244~04 1998-08-06 of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each OI components ~A), (B) and (C) is based on the total amount of components (A~ and (B).
The present invention further provides a molded article, especially a lamp cover, obtained by polymerizing and curing said methyl m.ethacrylic resin composition.
The present invention still further provides a method for producing a molded article, comprising the steps of mixing components (A), (B) and (C) to obtain a material for molding, and heating and curing the material for molding.
1~
DETAILED DESCRIPTION OF THE INVENTION
The methyl methacrylic resin composition of the present invention comprises the components of:
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can erfect radical polymeri~ation, (~) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially c-oss-linkedresinparticlesand(ii)Oto80partsbyweight CA 02244~04 1998-08-06 ofuncross-linkedresinparticles,whereinthetotalamount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weisht of a radical polymerization initiator, wherein the amount of each of components (A), (B) and (C) is based on the iotal amount of components (A) and (B).
~he ursaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, which is used as component (A) in the present invention, is preferably a mixtureofanunsaturatedmonomerhavingat leasttwodouble bonds which can effect radical polymerization and an 16 unsaturated monomer copolymeri~able with s~id unsaturated monomer. Hereinafter, the unsaturated monomer having at least two double bonds which can effect radical polymerization is called "a polyfunctional unsaturated monomer", andtheunsaturated monomer copolvmerizable with the polyfunctional unsaturated monomer is called "a monofunctional unsaturated monomer". lhe unsaturated monomer mixture preferably contains about 50 % by weight or more, more preferably about 55 % by weight or more, of said polyfunctional unsaturated monomer.
Examples of the polyfunctional unsaturated monomer CA 02244~04 1998-08-06 include allyl methacrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,3-butylene glycol di~meth)acrylate, 1,6-hexane diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, divinylbenzene, diallyl ph~h~late, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethyloimethane tetra(meth)acrylate, and the like. ~ere, the term "(meth)acrylate"representsbothacrylateandmethacrylate, and hereinafter, the term "(meth)" has an analogous meaning indicating the optional presence of a methyl substituent.
Among them, a polyfunctional unsaturated monomer having at least two methacryloxy groups as a double bond which can effect radical polymerization is preferred since the polyfunctional unsaturated monomer reacts readily with an unsaturated monomer copolymerizable with said polyfunctional unsaturated monomer and, thererore, there remains only a little amount of unsaturated monomer which hasnotreactedinthecuringreactionthereof. Amongthese, neopentyl glycol dimethacrylate is one of the most preferred examples. The polyfunctional unsaturated monomer can be used independently or in ~ombination of two or more.
CA 02244~04 1998-08-06 In the present invention, the monofunctional unsaturated monomer can be used with the polyfunctional unsaturated monomer and is not restricted as long as it has the copolymerizable property, and can be appropriately selected for use. Example of the monofunctional unsaturated monomer include esters of methacrylic acid or acrylicacidwithaliphatic,aromaticoralicyclicalcohols, such as methyl (meth)acrylate, ethyl ~meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, ~-ethylhexyl (meth)acrylate, lauryl ~meth)acrylate, tetrahydrofurfuryl (meth)acryiate, isoborny' (meth)acrylate, benzyl (meth)acrylate and cyclohexyl (meth)acrylate; (meth)acryl-based monomers such as hydroxyalkyl esters such 2S hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate; unsaturated acids such as acrylic acid ard methacrylic acid; styrene-based monomers such as styrene and ~-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; and monofunctional unsaturated monomers such as maleic anhydride, phenylmaleimide, cvclohexylmaleimide and vinyl acetate.
Among them, esters of methacrylic acid are preferred.
In the present invention, the above-mentioned monofunctional unsaturated monomer and/or polyfunctional unsaturated monomer can also be used with dissolving a CA 02244~04 1998-08-06 homo-polyme_ thereof and/or co-polymer thereof.
The methyl methacrylic resin composition of the present invention comprises about from 30 to about 60 % by weight, preferably about from 40 to about 55 % by weight, of the unsaturated monomer mixture component (A) based on the total amount of components (A) and (B). When the content of the unsaturated monomer mixture component (A) is less than bout 30 % by weignt, sufficient moldability is not obtained in molding the resin composition. On tne other hand, when the content is over about 60 % by weight, stickinessofamaterialtobemoldedwhichisobtainedafter kneading the resin composition is high and it is difficult to keep the form after kneading and, therefore, handling inbothcases is not good, undesirably. In additiontothat, whenthecontentisoverabout60%byweiaht,iticdifficult to obtain a molded article having a flat surface, undesirably, since a shrinkage of the molded article due to the polymerization becomes large.
The methyl methacrylic resin composition of the present invention comprises from about 40 to about 70 % by weight ofresinparticles ofcomponent (B) made of apolymer of a methyl methacrylic unsaturated monomer, based on the total amount of components (A) and (B), which comprise (i) partially cross-linked resin particles and (ii) uncross-linked resin particles. The resin particles of CA 02244~04 1998-08-06 component (B) made of a polymer of a methyl methacrylic unsaturated monomer are made from a copolymer comprising a methyl methacrylate monomer and an unsaturated monomer copolymerizable with methyl methacrylate, or the copolymer 6 and a homopolymer of methyl methacrylate, and the resin particles are preferably made from about ~0 ~ by weight or more, morepreferably about80%byweightormore,ofmethyl methacrylate based on the resin particles.
Examples of the unsaturated monomer copolymerizable with methyl methacrylate include the same monofunctional unsaturated monomers and the same polyfunctional unsaturated monomers as mentioned above.
Specific examples of the polyfunctional unsaturated monomers which are used as the unsaturated monomer copolymerizable with methyl methacrylate include, but are not limited to, allyl methacrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethvlene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,6-hexane diol di(meth)acrylate, neopentyl glycol di(meth)acrylate, divinylbenzene, diallyl phthalate, trimethylolpropane tri(meth)acryl te, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane 2~ tetra(meth)acrylate, and the like.
CA 02244~04 1998-08-06 Specific examples of the monofunctional unsaturated monomer include, but are not limited to, esters of methacrylic acid or acrylic acid with aliphatic, aromatic or alicyclic alcohols, such as methyl acrylate, ethyl 5 (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, ben2yl (meth)acrylate and cyclohexyl (meth)acrylate; (meth)acryl-based monomers such as hydroxyalkyl esters such as hydroxye~hyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate; unsaturated acids such as acrylic acid and methacrylic acid; styrene-based monomers such as styrene and ~-methylstyrene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; and monofunctional unsaturated monomers such as maleic anhydride, phenylmaleimide, cyclohexylmaleimide and vinyl acetate.
When component (B) is made, the unsaturated monomer 2~ of which component (B) is composed can be used with dissolving a homo-poiymer thereof and/or co-polymer thereof in the same way as mentioned regarding component (A).
The resin particles used as component (B) in the present invention are, fcr example, resin particles CA 02244~04 l998-08-06 obtainedbypolymerizationsuchasemulsionpolymerization, suspension polymerization and dispersion polymerization, and resin particles obtained by grinding a resin polymer, which is obtained by other polymerization, into pieces.
An average particle size of the resin particles, especially that ofpartially cross-linkedresinparticles~
is usually in the range of about i to about 100 ~ m. The size can be controlled by conducting a suitable polymerizationmethodwhichismentionedabove. Whenresin particles having a particle size less than about 1 ~ m are used, it tends to be difficult tO mix or knead the -esin particleswiththeunsaturatedmonomermixtureofcomponent (A). On the other hand, when resin particles having a particle size over about 100 ~ m are used, the form of the particles tends to be noticeable after molding.
The resin particles of component (B) comprise (i) from about 20 to about 100 parts by weight of partially cross-linked resin particles and (ii) from 0 to about 80 parts by weight Gf uncross-linkea resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight. When the ratio of the partially cross-linked resin particles accounts for less than about 20partsbyweightinthetotalamountoftheresinparticles 2a addins up to 100 parts by weight, the stickiness of the CA 02244~04 1998-08-06 composition is high, and the handling property deteriorates.
The ratio of the partially cross-linked resin particles accounting for about 20 to about 100 % by weight a of component (B) and the ratio of the uncross-linked resin particles accounting for 0 to about 80 % by weight of component (B), eachbeing based onthe total amount of these resin particles, can be appropriately selected depending on the use of the molded article to be obtained, provided that these -atios falls in the each above-mentioned range.
~mong these, the ratio of the partia1ly cross-linked resin particles is preferabiy from about 50 to about 100 % by weight.
The partially cross-linked resin particles in the la present invention swell and are not completely dissolved in solvents in which polymethylmethacrylate can be dissolved, such as acetone.
The partially cross-linked resin particles can be obtained, for example, by adding the polyfunctional unsaturated monomer when a mixture of about ~C % by weight or more of methylmethacrylate and an unsaturated monomer copolymeriza~le with methylmethacrylate is polymerized to obtain resin particles thereof or of a polymer thereof.
The resin particles of component (B) are contained in the present resin composition in an amount of about 40 to CA 02244~04 1998-08-06 about 70 % by weight, preferably about 45 to about 60 % by weight, based on the total amount of compounds (A) and (B).
Whenthe amountislesstnanabout40~byweight,stickiness of a material to be molded which is obtained after kneading a the resin composition is high and it is difficult to keep theformafterkneadingand,therefore,handlingisnotgood, undesirably. On the other hand, when the amount is more than about 70 % by weight, it is difficult to uniformly mix or knead the resin composition, undesir~Dly.
The resinparticlesc2noption211ycont2inagentssuch as an antioxidant, an ultraviolet-ray absorbing agent, a chain transfer agent, a releasing agent, a flame retardant and a dye, and these agents can be used in the resin composition of the present invention.
1~ A radical polymerization initiator is used as component (C) in the resin composition of the present composition, and it effects polymerization and curing of the unsaturated monomer mixture component (A).
Examples of the radical polymerization initiator include azo compounds such as 1,1'-a70bis(cycloh2xane-l-carbonitrile), 2,2'-azobis(2,4,4-trimethylpentene), 2,2'-azobis(2-methylpropane), 2-cyano-2-propylazoformamide, 2,2'-azobis(2-hydroxy-methylpropionate), 2,2'-azobis(2-methyl-butyronitrile), 2a 2,2'-azobisisobutyronitrile, 2~2~-azobis[2-(2-CA 02244~04 l998-08-06 imidazolin-~-yl)propane] and dimethyl-2,2~-azobis(2-methylpropionate); diacyl and/or dialkyl peroxide-based initiatorssuchasdicumylperoxide,t-butylcumylperoxide, di-t-butyl peroxide, benzoyl peroxide and lauroyl peroxide; peroxy ester-based initiators such as t-butyl peroxy-3,3,5-trimethylhexanoate,t-butylperoxyllaurate, t-butyl peroxy isobutyrate, t-butyl peroxy acetate, di-t-butyl peroxyhexahydro terephthalate, di-t-butyl peroxy a7elate, t-butyl peroxy-~-ethyl hexanoate~ 1,1,3,3-tetramethylbutyl peroxy-2-ethyl nexanoate and t-amyl peroxy-2-ethyl hexanoate; percarbonate-based initiators such as t-butyl peroxy allyl carbon-te and t-butyl peroxyisopropyl carbonate; and peroxy ~etal-based initiators such as l,l-di-t-butyl peroxycyclohexane, la l,l-di-t-butyl peroxy-3,3,5-trimethylcyclohexane and l,l-di-t-hexyl peroxy-3,3,5-trimethylcyclohexane.
These radical polymerlzation initiators can be used independently or in combination of two or more~
When a polymerization initiator which decomposes even at low temperature is used, lt may cause the radical polymerizatior. in mixing the resin composition or in storage after the mixing and, therefore, a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is about 60 ~C o_ higher is ~a preferablyusedinthepresentinvention. Ontheotherhand, CA 02244~04 1998-08-06 a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is over about 100 ~C is not industrially preferable, since it needs high temperature or much time for a curing reaction a of the unsaturated monomer mixture component (A) which is described later in detail. Therefore, a polymerization initiator having a decomposition temperature such that a 10-hour half-life temperature is in the r~nge of about 60 to about 100 ~C is preferably used, and by using sucr. a polymerization initiator, both an excellent preservative property of the resin composition, and desirable temperature andtimeforthecuringreactioncanbeachieved at the same time.
~he radical polymerization initiator component (C) is contained in the present resin composition in an amount of about 0.1 to about 5 % by weight, preferably about 0.1 to about 2 % by weight, based on the total amount of components (A) and (B). When the amount is less than about 0.1 ~ by weight, the radical polymerization reauires long period of time, and when the amount is more than about 5 % by weight, the unsaturated monomer mixture component (A) can not be polymerized steadily.
The resin composition of the present invention can further contain a releasing agent, an ultraviolet-ray 2~ absorbing agent, a dye, a pigment, a polymerization CA 02244~04 1998-08-06 inhibitor, a chain transfer agent, an antioxidant, a flame retardant, a reirforcing agent and the like. For example, an ultraviolet-ray a~sorbing agent can be contained in the methyl methacrylic resin composition of the present 5 invention in amount of about 10 to about 1000 ppm based on the total amount of components (A), (B) and (C).
The p-esent inventiGn also provides a method for producing a molded article using the methyl methacrylic resin composition.
The method for producing the molded article comprises steps of (i) mixing and aging the methyl methacrylic resin compositionof'hepresentinvention,and(ii)polymerizing and curing the resulting composition.
In the step of the mixing and aging the methyl methacrylic resin composition, components (A), (B) and (C) are mixed to obtain a final uniform resin composition.
Specific examples of the step include a step such that components (A), (B) and (C) zre mixed to obtzin a slurry of the resin composition, tAen the slurry is aged in an appropriate vessel.
A shape of the vessel is not particularly restricted.
Examples of the vessel include a cell composed OI at least two flat plates facing each other and a sealing material.
A material of the vessel ia not particularly restricted, 2~ provided that it is not dissolved in or is not corroded by CA 02244~04 1998-08-06 component (A) or (C).
Theresincompositionmixedmaybeenclosedinavessel, and heated for aging. During the aging, the unsaturated monomer mixture component (A) may be impregnated into the 6 resin particles component (B) and the uncross-linked resin pzrticles in the component (B), when it is used, may be dissolvedintheunsaturatedmonomermixturecomponent(A).
An appearance of the resin composition usually changes from a slurry form to a clay form during the aging, and the resin composition after tr.e aging, which is a so~t m~terial, can be used as a material to be molded.
The aging temperature preferably falls in the range of about 20 ~C to about 80~C. When the mixed resin composition is heated over about 80~C, undesirable polymerization and curing reaction may occur due to the added radical polymerization initiator. When the mixed resin composition is aged at a temperature lower than about 20~C, the aging requires ar. undesirable length of time.
The aging conditions, except the temperature, are chosen according tc the resin composition, especially to the kind of the resin particles component (B), the composition of the unsaturated monomer mixture component (A), the kind OI the radical polymerization initiator component (C) and the like.
26 For example, the mixing and the heating of the resin CA 02244~04 l998-08-06 composition can be conducted at the same time by selecting an appropriate temperature when the mixing and the aging of the resin composition are carried out. At that time, a known kneading apparatus such as a 2-axis extruder, an 6 almighty mixing apparatus, a kneader and a banbury mixer can be used as a ~neading apparatus.
Afterthemixingandagingstep,amaterialtobemolded is obtained. Thls materiai is soft and, therefore, has excellent handling property. The material can be easily processed and desirably shaped. For example, the material can be handled ln var-ous forms such as sheet, block, cake, rod, pellet, ribbon and slrand.
That is, after the mixing and aging step, polymerizing and curing steps are conducted, and the above-mentioned la material to be molded may be thrown into a mold of various shapes, pressed, heated, shaped and cured to obtain molded articles of various forms.
When a curing reaction by a radical polymerization reaction is conducted in the present inventionr a reaction temperature from about 80 to about 160 ~C is preferable.
When the temperature is lower than about 80 ~C, the curing reaction requires a long period of time and is industrially disadvantageous. On the other hand, when the temperature isoverabout160 ~C,decompositionandcolorationmayoccur, 2~ undesirably.
CA 02244~04 1998-08-06 Any method of molding can be used as long as the material to be molded is pressed, heated, shaped and cured.
Examples thereofinclude press molding, injection molding, transfer molding and the like.
When press molding is carried out, a press molding apparatus comprising a pressure-applying unit and a mold may be used. Temperature of a mold in press molding is preferablycontrolledtobeintherangeofzbout 80toabout 160 ~C.
The mold-surtace of the outer and inner molds may or may not have the same temperature provided the difference between outer mold surfacs and inner mold surface does not exceed about 20 ~C.
A mold compression pressure is usually in the range 1~ of about 20 to about 100 kg/cm2. When the pressure is lower than about 20 kg/cm2, defects such as inner cracks tend to be caused, and surface defects may be caused on the surface of the molded article by boiling of methyl methacrylate contained in the material to be molded. On the other hand, when the pressure is over about 100 ~g/cm2, the material to be molded may flow undesirably out of the mold during compression.
The molding conditions such zs the temperature of the mold, the mold compression pressure, a rate of a mold 2~ compression and a place at which the material to be molded CA 02244~04 1998-08-06 is thrown into the mold are selected depending on the shape of the molded article and tne period of time needed for producing the molded article.
When injection molding or transfer molding is carried out, an injection molding apparatus or a transfer molding apparatus comprising an injection unit and a mold compression unit is used.
A suitable screw used for a measurement or a injection has a pressure ratio of 1.5 or less. The screw may have a bac~-flow-preventing ring, which can be of a various structure, in vicinity of the top.
Temperature of a cylinder covering a screw and cr a pipe for iransfer of transfer molding is preferably controlled at about 60 ~C or less. When the temperature is la over about 60 ~C, a local-temperature increase may take place due to shearing heat generation between the screw and thecylinderorinthepipe duringthetransfer, andacuring reaction of the material may be initiated, undesirably.
When injection molding or transfer molding is carried out,temperatureofthe moldiscontrolledtobeintherange of about 80 to about 160 ~C. The mold-surface of the outer and inner molds may or may not have the same temperature provided the difference between outer mold surface and inner mold surface does not exceed about 20 ~C.
2~ A mold compression pressure and a clearance between CA 02244~04 1998-08-06 molds may be controlled constantly, or may be controlled continuously or gradually depending on the progress of the curing reaction.
The molding conditions of injection molding and transfer molding such as the ~emperatur2 of the mold, the mold compression pressure, a rate of a mold compression and a place at which the material to be molded is added into the mold are also selected depending on the shape of the molded article and the period of time needed for producing the molded article.
~ sdescribedabove,themoldedarticleisthusobtained in the present invention~ The molded article has a high hardnessofthesurfaceandanexcellentscratch-resistance.
The surface hardness thereof can be at least 3H, and is 16 usually 4~ or more of tne pencil hardness. In addition, the molded article has an excellent appearance without any defects such as cracks.
The moldedarticleofthepresent inventioncanbeused in variety of fields. Examples of the fields include automobile-related parts such as a tail-lamp cover, head-lamp cover, a meter panel, various windows and components for mirrors, construction materials such as commonly used windows and boards for room-compartments, coating materials used for, for example, a bath tub or a washstand, kitchenware such as resin tableware, parts for CA 02244~04 1998-08-06 2a appliances concerning running-water such as windows of microwave ovens, protecting front panels used for, for example, a liquid crystal display, other front panels for displays or various kinds of monitors, covers for various machines, lenses such as _resnel lenses, lenses for a watch and lenses for glasses, disk substrates used for, for example, compact disks or digita'-videc àis~s, ccvers for hot-water apparatuses using solar energy, protecting covers for solar batteries and various signboards.
The molded article of the present invention has a high transparency and an excellent weather-resistance as well as a high hardness of the surface and an excellent scratch-resistance and, therefore, may be preferably used inthefieldswhereinpropertiessuchasahightransparency, an excellent weather-resistance and an excellent scratch-resistance are needed. ~specially, the molded article is preferably used as a lamp cover in the various fields such as automobile, shipp-ng, _-rlin2 system, outdoor apparatuses and signals. Specific examples of the usage thereof include materials of covers for lamps such as a tail lamp, a head lamp, a fog lamp, a halogen lzmp, a metal halide lamp, a xenon lamp, a fluorescence mercury lamp and sodium lamp.
~s described above, the present invention provides methyl methacrylic resin compositions whicn have little CA 02244~04 1998-08-06 amount of scattering in the content and an excellent preservative property, and is able to give a molded article whichhasahightransparency,ahighhardnessofthesurface and an excellent scratch-resistance. The material to be molded comprising said methyl methacrylic resin composition is excellent ir.view of a handlins ?roper'y and amoldingproperty, andcangive anexcellent molded article having a gooa appearan.ce. AccQrai ng tO th~ ~resent invention, the molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistarce can be steadily and easily processed. The presert invention may be p_eferably used inthefieldswhereinpropertiessuchasahightransparency, ar. excellent weatr.~r-resistance and an excellent sc~atch-resistance are needed, ror example, in the field of a lamp cover.
The entire disclosure of the Japanese Patent Application No. 5-212942 _iled on August 7, lg97 ard the JapanesePatent Applicat-on No.l0-739l7 filed or March23, 1998, both indicating specification, claims and s~mmary, are incorporated herein by reference in their entirety.
EXAMPLES
The present invention is described in more detail by reference to the following Examples, which should not be CA 02244~04 1998-08-06 construed as a limitation upon the scope of the present invention.
In the Examples, the measurement of physical properties was conducted by the following methods.
(1) Handling property of the m-~ erial to be molded:
A handling propertv of the obtained m2terial to be molded was evaluated by the extent of stickiness thereof, whlch is determined by a method of touching while wearing a polyethylene glov~.
(2) Molding property of the material to be molded:
80 g OI the obtained material to be molded WâS thrown into a plate-form mold of 120 x 120 x 20 mm, and was subjected to thermal compression molding for 10 minutes under conditions of a temperature of 120 ~C and a mold compressionpressure Ot- 7 0 kg/cm2 tO obtaina~oldedarti-le.
Amoldingpropertyo_thematerialtobemoldedwasevaluated bv the appearance OI the obtained mol~ed article.
(3) Preservation property of the material to be molded:
A material to be molded was formed to be two plates having a thickness of about 5 mm. ~etween these plates, a thermocouple was placed. The thermocouple and the two plates were wrapped in aluminum foil and were placed in an air-oven at 90 ~C to carry out a test of a preservation property of the material to be molded. The change of 2a temperature was traced.
CA 02244~04 1998-08-06 A length of time needed for showing the maximum of calorification due to the polymerization was measured and the length of time gave a criterion for judçm~nt OI a preservation property of the material to be molded. The longer period of time means that the material to be molded has the better preservation property.
A material to be molded was formed to be two plates having a thickness of about 5 mm. ~etween these plates, a thermocouple was placed. The thermocouple and the two plates were wrapped in aluminum foil and were placed in an air-oven at 90 ~C to carry out a test of a preservation property of the material to be molded. The change of 2a temperature was traced.
CA 02244~04 1998-08-06 A length of time needed for showing the maximum of calorification due to the polymerization was measured and the length of time gave a criterion for judçm~nt OI a preservation property of the material to be molded. The longer period of time means that the material to be molded has the better preservation property.
(4) Scratch-resistQr.cc of a molded article:
Acco-ding to _~e pencil-scratching test of the Japanese St~ndards Association JIS-~5~00 method, a hardness of a molded material surface was evaluated by a measurement of a pencil hardness, which corresponds to the hardness of the surface. The larger pencil hardness means that the obtained molded article has the more excellent s~ratch-resistance.
1~ (5) T ansparency or a molded article:
In the following Examples 1 to 6 and Comparative Examples 1 to 2, the molded articles were obtained by the same method that is described in tne above (2) ~Molding propertyofthemateri21tob2 mGl ded". Theobtainedmolded articles were cut O"t into the square-rorm of ~A X ~A C~ and the total light transmission thereof was measured with a haze-meter to evaluate the transparency of the obtained molded articles.
In the following Examples 7 and 8, the total light 2~ ~ransmission of the obtained lamp covers W2S measured according to the Japanese Standards Association JIS-K7105 method to evaluate the transparency of the obtained lamp covers.
(6) Weather-resistance:
In ~ne following E~amples 7 and 8, aweather-resistance test was concucted by ~Xposin.S _he obta-'ne~ 1 aIl':p covers to light, using Sunshine we~her-oIr.eter (manl~factured by Suga Test Inst~uments Co, Lit.) The test was carried out at o3 C
for 1000 hollrs, using a carDon-arc lamp -s a light source 10 while water was atomi~ed for '8 minutes ir. every 2 hours.
After the test, the total light transmission of the ob~ained lamp covers was measured. The weather-res stance o_ the lamp cover was evaluated s~n basis of the difference of the total light t_ansmission thereof and the eye-estimated 15 changes of appearance of the lamp cover, such as coloring, before and after the exposure.
Example 1 Into a 1000 ml round-bottom lask were charged 28 parts 20 by weight of neopentyl glycol dimethacrylate ~NK ester NPG, manufactured by SHIN-NAKAMURACHEMICPLCO./ LTD.), 22 parts by weight of methyl methacrylate, 50 parts by weight of a partially cross-linkec resin. particle (Techlpolvmer MBX-5, manufactured by Sekisui Chemical Co, Ltd., in which non-dissolved material with acetone is 94.6 % ) and 0.23 parts by weight of t-butyl peroxyisopropyl carbonate as a polymerization initiator, and the resulting mixture was stirred and mixed to o~tain a methyl methacrylic resin composition in the form of slurry.
Acco-ding to _~e pencil-scratching test of the Japanese St~ndards Association JIS-~5~00 method, a hardness of a molded material surface was evaluated by a measurement of a pencil hardness, which corresponds to the hardness of the surface. The larger pencil hardness means that the obtained molded article has the more excellent s~ratch-resistance.
1~ (5) T ansparency or a molded article:
In the following Examples 1 to 6 and Comparative Examples 1 to 2, the molded articles were obtained by the same method that is described in tne above (2) ~Molding propertyofthemateri21tob2 mGl ded". Theobtainedmolded articles were cut O"t into the square-rorm of ~A X ~A C~ and the total light transmission thereof was measured with a haze-meter to evaluate the transparency of the obtained molded articles.
In the following Examples 7 and 8, the total light 2~ ~ransmission of the obtained lamp covers W2S measured according to the Japanese Standards Association JIS-K7105 method to evaluate the transparency of the obtained lamp covers.
(6) Weather-resistance:
In ~ne following E~amples 7 and 8, aweather-resistance test was concucted by ~Xposin.S _he obta-'ne~ 1 aIl':p covers to light, using Sunshine we~her-oIr.eter (manl~factured by Suga Test Inst~uments Co, Lit.) The test was carried out at o3 C
for 1000 hollrs, using a carDon-arc lamp -s a light source 10 while water was atomi~ed for '8 minutes ir. every 2 hours.
After the test, the total light transmission of the ob~ained lamp covers was measured. The weather-res stance o_ the lamp cover was evaluated s~n basis of the difference of the total light t_ansmission thereof and the eye-estimated 15 changes of appearance of the lamp cover, such as coloring, before and after the exposure.
Example 1 Into a 1000 ml round-bottom lask were charged 28 parts 20 by weight of neopentyl glycol dimethacrylate ~NK ester NPG, manufactured by SHIN-NAKAMURACHEMICPLCO./ LTD.), 22 parts by weight of methyl methacrylate, 50 parts by weight of a partially cross-linkec resin. particle (Techlpolvmer MBX-5, manufactured by Sekisui Chemical Co, Ltd., in which non-dissolved material with acetone is 94.6 % ) and 0.23 parts by weight of t-butyl peroxyisopropyl carbonate as a polymerization initiator, and the resulting mixture was stirred and mixed to o~tain a methyl methacrylic resin composition in the form of slurry.
6 After being deformed under the reduced pressure, the resincompositionwaspouredintoapolyethylenecont2iner, and ther. sealed in a bag, and left in ~ hc= a r d-y~r ât 60~C for 7 hours for agir.g. The resin comp~sition was cooled down io room temperalure, then, the ~G3 ar!d _he container were removed to obtain a material to be moided in the form of clay.
Thismaterialhadlittlestickinessandagoodhandling property. A molded article was obtained y using the material. The appearance of the arti clê was excellent without defects such as crackir,s and, therefo-e, it was recognizedthat the materialtobe molded has a good molding property. The pencil hardness of the article surface was 5~ andthetotallighttransmissionofthe articlewas g~.3%
and, therefore, it was recognized tha_ the a~t' cle has an excellent scratch-res-a~ar!ce -nd high _-ans ar2ncy.
A test of a p-eservatior property of-_he ma_ê~ial to be molded was conducted. A long period cf time was needed for showing the maximum of calorification due to the polymerization, of 41 minutes and, therefore, it was 26 recognized that the material to be molded has an excellent CA 02244504 l998-08-06 preservation property.
Example 2 Thesameprocedure asinExamplelwas conductedexcept 6 that 50 p~rts by weight of SUMTPEX XC-~A (m~ufactur~d by Sl~mitomo Chemical ~5. / __C., 'n WhiCn non-a' SSOl'Jed m-Lerial wi~h ace~or2 ls ?~.6 %~ wa -sed ac a pa__ial~y cross-linked resin particle instead of Techpolymer MBX-5 (manufactured ~y Sekisui Chemical Co, ~td.), to obtain a mâterial tO be ~olded in the fGrm of clay.
Thismaterialhadlittlestickinessandagoodhandling property. ~ molded article was obtained by using the material. The appear-nce of the article was exsellent without defects such as cracking and, therefore, it was recogni~edtha~the materialtobe molded has 2 good molding property. The pencil hardness of the ar~icle surface was 4u andthetot211ighttransmissionofthe articlewas9~.2 %
andr hereforef ~t WâS -eccgnized -hal _he ar-_ c'e has an excellent scratch-resistance and high transparency.
A test of a preservation property of the materlal to be molded was conducted. A long period of _ime was needed for sh.owlng the maximum of calorification due to the polvmerization, of 46 min~tes and, tnerefore, t was recognized that the material tc be molded has an excellent preservation property.
Example 3 The same procedure as in Example 2 was conducted except that 36 parts by weight or diethylene glycol dim~ethacrylate 5 (NK ester 2&, manufactured by SHI~-~AKAMURA CHEMTCAL CO., LTD.) was used instead of neopentyl glycol dimethacrylate and ~he aIrLount of met;rlyl met:rlacrylate was changed _c 14 parts by weight, to obta :~ G r.a~erial to 02 -mOldêd ir ~he orm GI C' ay.
This material had li tl2 stickinêss ard a good hanaling property. A molded artic7e was obtaired by using the material. The appearance of the article was excellent without defects such âS cracking nd, therefore, it was recognized that the material to be molded has a good molding 1~ property. The penc 1 hardn~ss or ~he articlc s~rf-ce WaS
4H and the total light transmission of the article was 90.7 96 and, therefore, it was recogni~ed that the article has an excellent scratch-resistance and righ transparency.
A test or a preservation propertv of the ma-erial to 20 be molded was conducted. ~ long period of timê w25 neêded for showir.g the maxim~l~r3 of caloritica~ion d~e _o thê
polymerization, of 50 minutês znd, therefore, it was recognized that the material to be molded has an excellent preservation property.
2~
Example 4 Thesameprocedure asinExample2 wasconductedexcept that the amount of the partially cross-linked resin particle, SUMIPEX XC-lA, was changed to 34 parts by weight, and an uncross-linXed resin particle~ CUMTPEX
(manufactured by Sumitomo Chemica1 Co., ~td.~ was adc -- or~' ly used ? 2r 2~.!0Ur!_ 0~ ~tS D~ '.Jcigr~t~ tC
obtain a material ~o De moldec in the form of clay.
Thismaterialhadlittlestickinessandagoodhandling roperty. A molded article was obtained ~y using the material. The appe2rance of the ~rticle was excellent without defects such as crac~ing and, therefore~ it w~s recognizedthat the~.al~rialtobe molded has a good molding property. The pencil hardness of the article surface was 4H andthetotallighttransmissionofthearticlewas93.9%
and, therefore, it was recogni2ed that tne article has an excellent scratch-resistance and high transparency.
A test of a preserv2tion property or the materi21 ~o be molded was cor.ducted A long period of time was needed for showing the m~ximllm of calorification due to the polymerization, of 45 minutes znd, therefore, it WâS
recognized 'hat the mâterial to be molced hac an exceller.t preservation property.
Example 5 Thesameprocedure asinExample4 wasconductedexcept that the amount of the partially cross-linked resin particle, SUMIPEX XC-lA, was changed to 49 parts by weight, and the amount of the uncross-linked resin particle, 6 SUMIPEX MHF, was chan~ed ~o 1 part by weight, -o obt ir. 2 material to be molded in the fcrm of clay.
Thismaterialhadlittlestickinessandagoodhandling roperry. .~ moldec ar_ cle was obtained ~y using the material. The appearance of tr.e ~rticle was excellent withoul defects such as crack rg and, hercf~rê, t was recognizedthat thematerialto be molded has a good molding property. The pencil hardness of the article surface was 5H andthetotalliqhttransmissionofthe articlewas93.7%
and, therefore, it was recognized that the article has an excellent scratch--esictance and high transparency.
A test of a preservation property of the materiai to be molded was conducted. .~ long period of time was needed for showing the maximum of calorification due to the polymeri7ation, of 45 miruies and, therefore, it was recognized that the mcteri21 to De molded has an excellent preservation property.
Example 6 Thesameprocedure asinExample4 wasconductedexcept that the amount of the partially cross-linked resin 3~
particle,SUMIPEXXC-lA,waschangedto47.5partsbyweight, and the amount of the uncross-linked resin particle, SUMIPEX MHF, was changed to 2.5 parts by w2ight, to obtain a material to be molded in the form of clay.
6 Th-smaterialhadlittlestickiressandagoodhandlin.g property. A molded article was o~taired ~y using the material. The appear-r.c~ Ot tne a-t cie was excellent wi ho_t de_2cts suc. GS c~2c~ing ~nd, _h_-__s~_~ it w~s recognized that the materialto~e molded has a good molding property. The pencil hardness of the article surface was 5~ and ~he ~otallighttrarsmissiono~ _he a-ticle-was93.7~
and, therefore, t was recognized tha~ ~ne _r~icLe r.as an excellent scratch-resistance an~ high =-a-!sp--rencv.
A test of a preservation property o_ ~ne m~terlal to be molded was conducted. A long period of time was needed for showing the maximum of calorification due to the polymerization, of 5 minutes ~nd, ~herefore, it was recognized that the material to be molded has an excellenT
prese~a~ion property.
Comparative Example 1 The stirring and mixing were conducted in the same manner as in Example ~ except that methyl methacrylat~ was used instead of neoper.tyl glycol dimethacrylate, that is, the total amount of methyl methac-ylate was changed to 50 parts by weight andneopentyl glyccl dimethacrylate was not used. Flowability was lost during the stirring, and uniform mixing became impossible.
The resulting mixture was poured, as it was, irto a a polyethylene contair.erJ and ~her sea'ed in _ b c, -n.d lett in z hot air dryer at 60 C for 7 hours for aginS. The resir.
composition was cooled down to room temperature, then, the bag and the contai~2r were remLoved to obtain a malerial to be molded.
The material was in the wet-chalk-like form and the nandling property was not good. The materi_ genGra~ed strong odor of methyl metnacrylate. The thermal compression molding was conducted in the same manner as in Example 1, to obtal~ a molded article. ~he article had a 16 lot ofpartswherethecuring-~asnotenough, ardthe arti~le had a lot of cracks.
A test of a preservation property of the material to be molded was conducted. A short period of time was needed for showing the maximum of calorification due to the polymeri~ation, of 31 minutes and, therGrore, it was recogni7ed that Ihe material to be molded does not have a er.ough preserva~ior property.
Comparative Example 2 Ir.to alOOOmlround-bottomflaskwerecharged20parts by weight ofneopentyl glycol dimethacrylate ~NK esterNPG, manufactured by SHIN-NAKAMURA C~MICAL CO.~ ~TD.) and 80 parts by weight Qf methyl methacrylate incluaing 9~ by weight of polymethyl methacrylate having an average 5 polymerization degree of about 13,000. Into the mixture wereaddedO.0025%byweightofcumylperoxydecanoate,0.2%
by weight of di-t-butyl peroxide and ~.01 % by weight of 2,3-di~.ethyl-2,3-c D:rLs~_Du _:~2 -~d thC ~es~ _-~g ,Lix~ure was stirred and mixed to o~tain a methyl methacrylic resin composition.
This resin composition was poured into a cell comprising glass plates (thickness: 5 ~rn,) cnd G gasket made of vinyl chloride resin insertec between.the glass plates so tha' the clearance between them was 5 mm, and left in a water bath at 60~C for 2.5 hours for zging. The composition was cooled down to room temperature, then, the glass plates were removed to obtain a partially polymerized material in the form of gel.
A ~est of a preserva~ion p-operly of the material tc be moldea WGS concucted. ~P sh3r~ per-od o~ _ime W2S reeded for showing the maximum of calorific~tion due to the polymerization, of 26 minutes and, therefore, it was recognized that the material tO be molded ~oes not have a enough preservation property.
Example 7 Into alOOO mlround-bottomflaskwerecharged28parts by weight of neopentyl glycol dimethacrylate, NR ester NPG, 22partsbyweightofmethylmethacrylate,36partsbyweight ofthepartiallycross-linkedrcs~npart cle~SUMIPEXXC-~, 14 parts by weight Ot- ~he un.cross-linked resin par~icle, SUMIPEX M~F and 0.23 parts by weight of t-butyl peroxyisopropyl carbonate as a polymerization initiator, ard the ~esulting mixtu~e was stirred and mixed to o~tain a methyl methacrylic resin compositior in the rorm of s _~ ~y .
After being derormed under tAe reduced pressure, the resin composition was sandwiched between glass plates (thickness: 5 ~m) carrying on inner surface thereof a polyethylenefilmpasted, andthesurroundingsthereorwere sealed by a gasket made of a vinyl chloride resin inserted between the glass plates so that the clearance betweer.them was 5 mm, and left in a hot air dryer at 60~C for 7 hours for aging. The composition was cooled down to room ~emperature, then~ the ylass plates and the polyethylene film were removed to obtair a mate~ial _c be ~olded i~ the form of clay.
Thismaterialhadlittlestickiness andagoodhandling property. 80 g of the obtained material ~o be molded was thrown into a plate-form mold of 120 x 120 x 20 mm, and was subjected to thermalcompression moldingfor lO minutes under conditions of a temperature of 120 ~C and a mold compression pressure of 70 kg/cm2 to obtain a lamp cover.
The appearance of the lamp cover was excellent without 6 defects such as cracking and, therefore, it was recognized that the materi2l to De molded has a goo~ molding property.
The pencil hardness of the lamp ccver surface was 4H and the tct~l light trancmis_ion or the lamp cover was 93.0 %
~nd, therefo_e, it waC recogni~ed that the ;~mp co~er has ar. excellent scratch-resistance and hign transparency.
A weather-resistance test was conducted by exposing ~he 03t~ined la~p cover tO light. After th~s lO00-hour exposure, the lamp cover kept high transparency, of 92.6 ~
of the total light ~_âr.smissior and any char.gss/ such 2S
coloring, was not observed in appearance of the lamp cover before and after the exposure.
Example 8 Ir.to a kneader were charged 25 parts by weight of reopenlyl glycol dimethacrvla~e, ~K esier NPE~ 20 parts by weight of methyl methacrylate, 40 parts by weight of the partially cross-linked resin particle, SUMIPEX XC-lA, 15 parts by weight of the uncross-linked resin pa-ticle, SUMIPEX MHF and 0.23 parts by weight of t-butyl 26 peroxyisopropyl carbonate as a polymeri7ation initiator, CA 02244504 l998-08-06 and the resultins mixture was kneaded for 2 hours, while keeping a temperature of 70 ~C with a circulation of hot-water. The kneaded mixture was cooled down to room temperature to obtain a material to be molded in the form 6 of clay.
Thismaterialhad ittlesrickiressanaagco~hancling property. The obtzined materi~l to be molded was thrown into a ir.jection molding apparatus for a thermosetting resin having a plate-form mcld ~or lamp cover of 120 x 120 x ~0 mn, and was subjected IO injec_ion molding zt a mold tempe-ztlre o- 133 ~C to obta-.-e~ a l~mp cover. The ap e~rance of _ne lamp cover was excellcnt without defects such as cracking and, therefore, it was recognized that the material tobe molded has a good molding 13 property. The pencil hardness of the lamp cover surface was 4H and the total light transmission of the lamp cover was 92.5 ~ and, therefore, it WaS recogni~ed that the lamp cover has an excellent scratch-resistznce and nigh transparency.
A weather-resistance test was conducted by exposing the obtained lamp cover ~o light. Af~er l h2 ~000-hour exposure, the lamp cove~ kept high transpzrency, of ~1.8 %
of thG lotzl l~sht trancmissior. ~nd any changes, such .~s coloring, was not observed in appearance of the lamp cover 2~ before and after the exposure.
Thismaterialhadlittlestickinessandagoodhandling property. A molded article was obtained y using the material. The appearance of the arti clê was excellent without defects such as crackir,s and, therefo-e, it was recognizedthat the materialtobe molded has a good molding property. The pencil hardness of the article surface was 5~ andthetotallighttransmissionofthe articlewas g~.3%
and, therefore, it was recognized tha_ the a~t' cle has an excellent scratch-res-a~ar!ce -nd high _-ans ar2ncy.
A test of a p-eservatior property of-_he ma_ê~ial to be molded was conducted. A long period cf time was needed for showing the maximum of calorification due to the polymerization, of 41 minutes and, therefore, it was 26 recognized that the material to be molded has an excellent CA 02244504 l998-08-06 preservation property.
Example 2 Thesameprocedure asinExamplelwas conductedexcept 6 that 50 p~rts by weight of SUMTPEX XC-~A (m~ufactur~d by Sl~mitomo Chemical ~5. / __C., 'n WhiCn non-a' SSOl'Jed m-Lerial wi~h ace~or2 ls ?~.6 %~ wa -sed ac a pa__ial~y cross-linked resin particle instead of Techpolymer MBX-5 (manufactured ~y Sekisui Chemical Co, ~td.), to obtain a mâterial tO be ~olded in the fGrm of clay.
Thismaterialhadlittlestickinessandagoodhandling property. ~ molded article was obtained by using the material. The appear-nce of the article was exsellent without defects such as cracking and, therefore, it was recogni~edtha~the materialtobe molded has 2 good molding property. The pencil hardness of the ar~icle surface was 4u andthetot211ighttransmissionofthe articlewas9~.2 %
andr hereforef ~t WâS -eccgnized -hal _he ar-_ c'e has an excellent scratch-resistance and high transparency.
A test of a preservation property of the materlal to be molded was conducted. A long period of _ime was needed for sh.owlng the maximum of calorification due to the polvmerization, of 46 min~tes and, tnerefore, t was recognized that the material tc be molded has an excellent preservation property.
Example 3 The same procedure as in Example 2 was conducted except that 36 parts by weight or diethylene glycol dim~ethacrylate 5 (NK ester 2&, manufactured by SHI~-~AKAMURA CHEMTCAL CO., LTD.) was used instead of neopentyl glycol dimethacrylate and ~he aIrLount of met;rlyl met:rlacrylate was changed _c 14 parts by weight, to obta :~ G r.a~erial to 02 -mOldêd ir ~he orm GI C' ay.
This material had li tl2 stickinêss ard a good hanaling property. A molded artic7e was obtaired by using the material. The appearance of the article was excellent without defects such âS cracking nd, therefore, it was recognized that the material to be molded has a good molding 1~ property. The penc 1 hardn~ss or ~he articlc s~rf-ce WaS
4H and the total light transmission of the article was 90.7 96 and, therefore, it was recogni~ed that the article has an excellent scratch-resistance and righ transparency.
A test or a preservation propertv of the ma-erial to 20 be molded was conducted. ~ long period of timê w25 neêded for showir.g the maxim~l~r3 of caloritica~ion d~e _o thê
polymerization, of 50 minutês znd, therefore, it was recognized that the material to be molded has an excellent preservation property.
2~
Example 4 Thesameprocedure asinExample2 wasconductedexcept that the amount of the partially cross-linked resin particle, SUMIPEX XC-lA, was changed to 34 parts by weight, and an uncross-linXed resin particle~ CUMTPEX
(manufactured by Sumitomo Chemica1 Co., ~td.~ was adc -- or~' ly used ? 2r 2~.!0Ur!_ 0~ ~tS D~ '.Jcigr~t~ tC
obtain a material ~o De moldec in the form of clay.
Thismaterialhadlittlestickinessandagoodhandling roperty. A molded article was obtained ~y using the material. The appe2rance of the ~rticle was excellent without defects such as crac~ing and, therefore~ it w~s recognizedthat the~.al~rialtobe molded has a good molding property. The pencil hardness of the article surface was 4H andthetotallighttransmissionofthearticlewas93.9%
and, therefore, it was recogni2ed that tne article has an excellent scratch-resistance and high transparency.
A test of a preserv2tion property or the materi21 ~o be molded was cor.ducted A long period of time was needed for showing the m~ximllm of calorification due to the polymerization, of 45 minutes znd, therefore, it WâS
recognized 'hat the mâterial to be molced hac an exceller.t preservation property.
Example 5 Thesameprocedure asinExample4 wasconductedexcept that the amount of the partially cross-linked resin particle, SUMIPEX XC-lA, was changed to 49 parts by weight, and the amount of the uncross-linked resin particle, 6 SUMIPEX MHF, was chan~ed ~o 1 part by weight, -o obt ir. 2 material to be molded in the fcrm of clay.
Thismaterialhadlittlestickinessandagoodhandling roperry. .~ moldec ar_ cle was obtained ~y using the material. The appearance of tr.e ~rticle was excellent withoul defects such as crack rg and, hercf~rê, t was recognizedthat thematerialto be molded has a good molding property. The pencil hardness of the article surface was 5H andthetotalliqhttransmissionofthe articlewas93.7%
and, therefore, it was recognized that the article has an excellent scratch--esictance and high transparency.
A test of a preservation property of the materiai to be molded was conducted. .~ long period of time was needed for showing the maximum of calorification due to the polymeri7ation, of 45 miruies and, therefore, it was recognized that the mcteri21 to De molded has an excellent preservation property.
Example 6 Thesameprocedure asinExample4 wasconductedexcept that the amount of the partially cross-linked resin 3~
particle,SUMIPEXXC-lA,waschangedto47.5partsbyweight, and the amount of the uncross-linked resin particle, SUMIPEX MHF, was changed to 2.5 parts by w2ight, to obtain a material to be molded in the form of clay.
6 Th-smaterialhadlittlestickiressandagoodhandlin.g property. A molded article was o~taired ~y using the material. The appear-r.c~ Ot tne a-t cie was excellent wi ho_t de_2cts suc. GS c~2c~ing ~nd, _h_-__s~_~ it w~s recognized that the materialto~e molded has a good molding property. The pencil hardness of the article surface was 5~ and ~he ~otallighttrarsmissiono~ _he a-ticle-was93.7~
and, therefore, t was recognized tha~ ~ne _r~icLe r.as an excellent scratch-resistance an~ high =-a-!sp--rencv.
A test of a preservation property o_ ~ne m~terlal to be molded was conducted. A long period of time was needed for showing the maximum of calorification due to the polymerization, of 5 minutes ~nd, ~herefore, it was recognized that the material to be molded has an excellenT
prese~a~ion property.
Comparative Example 1 The stirring and mixing were conducted in the same manner as in Example ~ except that methyl methacrylat~ was used instead of neoper.tyl glycol dimethacrylate, that is, the total amount of methyl methac-ylate was changed to 50 parts by weight andneopentyl glyccl dimethacrylate was not used. Flowability was lost during the stirring, and uniform mixing became impossible.
The resulting mixture was poured, as it was, irto a a polyethylene contair.erJ and ~her sea'ed in _ b c, -n.d lett in z hot air dryer at 60 C for 7 hours for aginS. The resir.
composition was cooled down to room temperature, then, the bag and the contai~2r were remLoved to obtain a malerial to be molded.
The material was in the wet-chalk-like form and the nandling property was not good. The materi_ genGra~ed strong odor of methyl metnacrylate. The thermal compression molding was conducted in the same manner as in Example 1, to obtal~ a molded article. ~he article had a 16 lot ofpartswherethecuring-~asnotenough, ardthe arti~le had a lot of cracks.
A test of a preservation property of the material to be molded was conducted. A short period of time was needed for showing the maximum of calorification due to the polymeri~ation, of 31 minutes and, therGrore, it was recogni7ed that Ihe material to be molded does not have a er.ough preserva~ior property.
Comparative Example 2 Ir.to alOOOmlround-bottomflaskwerecharged20parts by weight ofneopentyl glycol dimethacrylate ~NK esterNPG, manufactured by SHIN-NAKAMURA C~MICAL CO.~ ~TD.) and 80 parts by weight Qf methyl methacrylate incluaing 9~ by weight of polymethyl methacrylate having an average 5 polymerization degree of about 13,000. Into the mixture wereaddedO.0025%byweightofcumylperoxydecanoate,0.2%
by weight of di-t-butyl peroxide and ~.01 % by weight of 2,3-di~.ethyl-2,3-c D:rLs~_Du _:~2 -~d thC ~es~ _-~g ,Lix~ure was stirred and mixed to o~tain a methyl methacrylic resin composition.
This resin composition was poured into a cell comprising glass plates (thickness: 5 ~rn,) cnd G gasket made of vinyl chloride resin insertec between.the glass plates so tha' the clearance between them was 5 mm, and left in a water bath at 60~C for 2.5 hours for zging. The composition was cooled down to room temperature, then, the glass plates were removed to obtain a partially polymerized material in the form of gel.
A ~est of a preserva~ion p-operly of the material tc be moldea WGS concucted. ~P sh3r~ per-od o~ _ime W2S reeded for showing the maximum of calorific~tion due to the polymerization, of 26 minutes and, therefore, it was recognized that the material tO be molded ~oes not have a enough preservation property.
Example 7 Into alOOO mlround-bottomflaskwerecharged28parts by weight of neopentyl glycol dimethacrylate, NR ester NPG, 22partsbyweightofmethylmethacrylate,36partsbyweight ofthepartiallycross-linkedrcs~npart cle~SUMIPEXXC-~, 14 parts by weight Ot- ~he un.cross-linked resin par~icle, SUMIPEX M~F and 0.23 parts by weight of t-butyl peroxyisopropyl carbonate as a polymerization initiator, ard the ~esulting mixtu~e was stirred and mixed to o~tain a methyl methacrylic resin compositior in the rorm of s _~ ~y .
After being derormed under tAe reduced pressure, the resin composition was sandwiched between glass plates (thickness: 5 ~m) carrying on inner surface thereof a polyethylenefilmpasted, andthesurroundingsthereorwere sealed by a gasket made of a vinyl chloride resin inserted between the glass plates so that the clearance betweer.them was 5 mm, and left in a hot air dryer at 60~C for 7 hours for aging. The composition was cooled down to room ~emperature, then~ the ylass plates and the polyethylene film were removed to obtair a mate~ial _c be ~olded i~ the form of clay.
Thismaterialhadlittlestickiness andagoodhandling property. 80 g of the obtained material ~o be molded was thrown into a plate-form mold of 120 x 120 x 20 mm, and was subjected to thermalcompression moldingfor lO minutes under conditions of a temperature of 120 ~C and a mold compression pressure of 70 kg/cm2 to obtain a lamp cover.
The appearance of the lamp cover was excellent without 6 defects such as cracking and, therefore, it was recognized that the materi2l to De molded has a goo~ molding property.
The pencil hardness of the lamp ccver surface was 4H and the tct~l light trancmis_ion or the lamp cover was 93.0 %
~nd, therefo_e, it waC recogni~ed that the ;~mp co~er has ar. excellent scratch-resistance and hign transparency.
A weather-resistance test was conducted by exposing ~he 03t~ined la~p cover tO light. After th~s lO00-hour exposure, the lamp cover kept high transparency, of 92.6 ~
of the total light ~_âr.smissior and any char.gss/ such 2S
coloring, was not observed in appearance of the lamp cover before and after the exposure.
Example 8 Ir.to a kneader were charged 25 parts by weight of reopenlyl glycol dimethacrvla~e, ~K esier NPE~ 20 parts by weight of methyl methacrylate, 40 parts by weight of the partially cross-linked resin particle, SUMIPEX XC-lA, 15 parts by weight of the uncross-linked resin pa-ticle, SUMIPEX MHF and 0.23 parts by weight of t-butyl 26 peroxyisopropyl carbonate as a polymeri7ation initiator, CA 02244504 l998-08-06 and the resultins mixture was kneaded for 2 hours, while keeping a temperature of 70 ~C with a circulation of hot-water. The kneaded mixture was cooled down to room temperature to obtain a material to be molded in the form 6 of clay.
Thismaterialhad ittlesrickiressanaagco~hancling property. The obtzined materi~l to be molded was thrown into a ir.jection molding apparatus for a thermosetting resin having a plate-form mcld ~or lamp cover of 120 x 120 x ~0 mn, and was subjected IO injec_ion molding zt a mold tempe-ztlre o- 133 ~C to obta-.-e~ a l~mp cover. The ap e~rance of _ne lamp cover was excellcnt without defects such as cracking and, therefore, it was recognized that the material tobe molded has a good molding 13 property. The pencil hardness of the lamp cover surface was 4H and the total light transmission of the lamp cover was 92.5 ~ and, therefore, it WaS recogni~ed that the lamp cover has an excellent scratch-resistznce and nigh transparency.
A weather-resistance test was conducted by exposing the obtained lamp cover ~o light. Af~er l h2 ~000-hour exposure, the lamp cove~ kept high transpzrency, of ~1.8 %
of thG lotzl l~sht trancmissior. ~nd any changes, such .~s coloring, was not observed in appearance of the lamp cover 2~ before and after the exposure.
Claims (18)
1. A methyl methacrylic resin composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each of components (A), (B) and (C) is based on the total amount of components (A) and (B).
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each of components (A), (B) and (C) is based on the total amount of components (A) and (B).
2. A resin composition according to Claim 1, wherein the unsaturated monomer mixture comprises 50 % by weight or more of the unsaturated monomer having a least two double bonds which can effect radical polymerization.
3. A resin composition according to Claim 1 or 2, wherein component (B) consists of resin particles made of a polymer of a methyl methacrylic unsaturated monomer consisting of partially cross-linked resin particles.
4. A resin composition according to Claim 1 or 2, wherein component (B) consists of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 60 to 80 parts by weight of partially cross-linked resin particles and (ii) 20 to 40 parts by weight of uncross-linked resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight.
5. A resin composition according to any one of Claims 1 to 4, wherein the unsaturated monomer having at least two double bonds which can effect radical polymerization is an unsaturated monomer having at least two methacryloxy groups.
6. A resin composition according to any one of Claims 1 to 4, wherein the partially cross-linked resin particles have an average particle size of 1 to 100 µm.
7. A resin composition according to any one of Claims 1 to 4, wherein the polymerization initiator has a 10-hour half-life temperature of 60 °C or higher.
8. A resin composition according to any one of Claims 1 to 4, wherein the unsaturated monomer mixture comprises 50 % by weight or more of the unsaturated monomer having at least two double bonds which can effect radical polymerization, the unsaturated monomer having at least two double bonds is an unsaturated monomer having at least two methacryloxy groups, the partially cross-linked resin particles have an average particle size of 1 to 100 µm and the polymerization initiator has a 10-hour half-life temperature of 60 to 100 °C.
9. A resin composition according to any one of Claims 1 to 8, wherein the unsaturated monomer having at least two double bonds which can effect radical polymerization is neopentyl glycol dimethacrylate.
10. A resin composition according to Claim 1 or 8, which comprises an ultraviolet-ray absorbing agent in an amount of 10 to 1000 ppm based on the total amount of components (A), (B) and (C).
11. A molded article obtained by polymerizing and curing a resin composition according to Claim 1 or 8.
12. A lamp cover obtained by polymerizing and curing a resin composition according to Claim 1 or 8.
13. A method for producing a molded article comprising steps of:
(I) mixing and aging a methyl methacrylic resin.
composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each or components (A), (B) and (C) is based on the total amount of components (A) and (B), to obtain a material to be molded, and (II) polymerizing and curing the material.
(I) mixing and aging a methyl methacrylic resin.
composition comprising :
(A) 30 to 60 % by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization, (B) 40 to 70 % by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles, wherein the total amount of the partially cross-linked resin particles and the uncross-linked resin particles adds up to 100 parts by weight and (C) 0.1 to 5 % by weight of a radical polymerization initiator, wherein the amount of each or components (A), (B) and (C) is based on the total amount of components (A) and (B), to obtain a material to be molded, and (II) polymerizing and curing the material.
14. A method for producing a molded article according to Claim 13, wherein a methyl methacrylic resin composition comprises the unsaturated monomer having at least two double bonds which can effect radical polymerization is an unsaturated monomer having at least two methacryloxy groups, the partially cross-linked resin particles having an average particle size of 1 to 100 µ m, and the polymerization initiator having a 10-hour half-life temperature of 60 °C or higher.
15. A method according to Claim 13 or 14, wherein the polymerizing and curing is conducted by an injection molding method, a compression molding method or a transition molding method.
16. A method according to Claim 13 or 14, wherein the aging is conducted at a temperature of 20°C to 30°C.
17. A method according to Claim 13 or 14, wherein the polymerizing and curing is conducted at a temperature of 80°C to 160°C.
18. A method according to Claim 13 or 14, wherein the aging is conducted at a temperature of 20°C to 80°C and the polymerizing and curing is conducted at a temperature or 80°C to 160°C.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09-212942 | 1997-08-07 | ||
| JP21294297 | 1997-08-07 | ||
| JP10-073917 | 1998-03-23 | ||
| JP07391798A JP3919925B2 (en) | 1997-08-07 | 1998-03-23 | RESIN COMPOSITION, MOLDED BODY THEREOF, AND METHOD FOR PRODUCING MOLDED BODY |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2244504A1 true CA2244504A1 (en) | 1999-02-07 |
Family
ID=26415062
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002244504A Abandoned CA2244504A1 (en) | 1997-08-07 | 1998-08-06 | Methyl methacrylic resin composition, molded article comprising the same and production of the molded article |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US6075094A (en) |
| EP (1) | EP0896007B1 (en) |
| JP (1) | JP3919925B2 (en) |
| KR (1) | KR19990023446A (en) |
| CA (1) | CA2244504A1 (en) |
| DE (1) | DE69815606T2 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002539291A (en) * | 1999-03-16 | 2002-11-19 | ゼットエムエス， エルエルシー | Precision integrated articles |
| US6416690B1 (en) | 2000-02-16 | 2002-07-09 | Zms, Llc | Precision composite lens |
| JP2003073430A (en) * | 2001-09-04 | 2003-03-12 | Sumitomo Chem Co Ltd | Resin composition, molding and method for producing molding |
| KR100796435B1 (en) * | 2005-08-24 | 2008-01-21 | 주식회사 엘지화학 | Artificial marble containing styrene methylmethacrylate chip and lighting fixtures using the same |
| JP2007084783A (en) * | 2005-08-24 | 2007-04-05 | Nippon Shokubai Co Ltd | Curable composition and cured product |
| KR100643399B1 (en) * | 2005-09-12 | 2006-11-10 | 박설환 | Radiating pipe and manufacturing method thereof, and radiator using that |
| JP5210858B2 (en) * | 2006-03-17 | 2013-06-12 | 株式会社きもと | Binder composition for polyester film and optical film using the same |
| ITVR20070078A1 (en) * | 2007-06-05 | 2008-12-06 | Aros Srl | COMPOSITION AND PROCEDURE FOR OBTAINING ARTIFICIAL STONE MATERIAL |
| JP2011063698A (en) * | 2009-09-16 | 2011-03-31 | Idemitsu Kosan Co Ltd | Raw material composition for resin for optical part and optical part |
| CN112867772A (en) * | 2018-10-18 | 2021-05-28 | 汉高知识产权控股有限责任公司 | Two-part, cyanoacrylate/free radical curable adhesive systems |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4396476A (en) * | 1979-02-01 | 1983-08-02 | Dentsply Research & Development Corporation | Blend of cross-linked polymer, swelling monomer and cross-linking agent and curing process |
| EP0014515B2 (en) * | 1979-02-01 | 1991-03-13 | Dentsply International, Inc. | Hardenable compositions, process to make a shaped article therefrom and dental appliance comprising it |
| US4396377A (en) * | 1980-04-07 | 1983-08-02 | Dentsply Research & Development Corporation | Dental appliances having interpenetrating polymer networks |
| US4698373A (en) * | 1981-01-21 | 1987-10-06 | Dentsply Research & Development Corp. | Stable one part dental compositions employing ipn technology |
| IL64757A0 (en) * | 1981-01-21 | 1982-03-31 | Dentsply Int Inc | Hardenable polymer compositions and production of shaped articles therefrom |
| JPS622201A (en) * | 1985-06-28 | 1987-01-08 | Kyowa Gas Chem Ind Co Ltd | Lens for lamp |
| JPH0667991B2 (en) * | 1985-10-01 | 1994-08-31 | 株式会社クラレ | Method for producing methacrylic resin molded article |
| JPS6335508A (en) * | 1986-07-31 | 1988-02-16 | G C Dental Ind Corp | Resin composition for denture base |
| DE3642212A1 (en) * | 1986-12-10 | 1988-06-23 | Espe Stiftung | POLYMERIZABLE MEASURES, METHOD FOR THEIR PRODUCTION AND THEIR USE AS DENTAL MEASURES |
| JPS63182315A (en) * | 1987-01-22 | 1988-07-27 | Kyowa Gas Chem Ind Co Ltd | Syrup composition |
| US5004785A (en) * | 1987-11-30 | 1991-04-02 | Mitsubishi Rayon Co., Ltd. | Light-diffusing methacrylic resin and process for production thereof |
| US4963624A (en) * | 1988-02-17 | 1990-10-16 | Mitsubishi Rayon Co., Ltd. | Process for producing light-diffusing methacrylic resin article |
| JPH01282208A (en) * | 1988-05-09 | 1989-11-14 | Mitsui Toatsu Chem Inc | Boilproof acrylic syrup composition |
| JP3433826B2 (en) * | 1993-09-03 | 2003-08-04 | 株式会社クラレ | Thermosetting resin composition |
| US5705552A (en) * | 1993-11-26 | 1998-01-06 | Aristech Chemical Corporation | Thermoformable acrylic sheet having uniform distribution of color and mineral filler |
| JPH09111086A (en) * | 1995-10-13 | 1997-04-28 | Mitsubishi Rayon Co Ltd | Resin composition, acrylic premix and production of acrylic artificial marble |
| US5880207A (en) * | 1995-10-17 | 1999-03-09 | Ici Acrylics Inc. | Acrylic compositions |
-
1998
- 1998-03-23 JP JP07391798A patent/JP3919925B2/en not_active Expired - Lifetime
- 1998-08-06 CA CA002244504A patent/CA2244504A1/en not_active Abandoned
- 1998-08-06 EP EP98306307A patent/EP0896007B1/en not_active Expired - Lifetime
- 1998-08-06 DE DE69815606T patent/DE69815606T2/en not_active Expired - Lifetime
- 1998-08-07 US US09/131,335 patent/US6075094A/en not_active Expired - Fee Related
- 1998-08-07 KR KR1019980032142A patent/KR19990023446A/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH11106449A (en) | 1999-04-20 |
| US6075094A (en) | 2000-06-13 |
| JP3919925B2 (en) | 2007-05-30 |
| DE69815606D1 (en) | 2003-07-24 |
| KR19990023446A (en) | 1999-03-25 |
| EP0896007B1 (en) | 2003-06-18 |
| DE69815606T2 (en) | 2004-05-13 |
| EP0896007A1 (en) | 1999-02-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |