CN1205341A - Synthetic method of AB-type block polymer and prepared block polymer thereof - Google Patents
Synthetic method of AB-type block polymer and prepared block polymer thereof Download PDFInfo
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- CN1205341A CN1205341A CN 97106509 CN97106509A CN1205341A CN 1205341 A CN1205341 A CN 1205341A CN 97106509 CN97106509 CN 97106509 CN 97106509 A CN97106509 A CN 97106509A CN 1205341 A CN1205341 A CN 1205341A
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Abstract
An AB-type block copolymer features that its block A is polyvinyl acetate and its block B is the polymer of polystyrene and methyl polyacrylate, and is prepared through the reaction of ethylene acetate on carbon tetrachloride under existance of trigger to generate polyvinyl acetate as prepolymer, and the reaction of said prepolymer with ethyl monomer under existance of catalyst. The block copolymer features low distribution index of molecular weights and clear structure.
Description
The present invention relates to a kind of Polymer Synthesizing method of AB block copolymer, the di-block copolymer that this AB block copolymer is made up of polyvinyl acetate (PVA) and other polymers of vinyl monomers.
As everyone knows, polymer homopolymer and the multipolymer that is polymerized by small molecule monomer obtained widespread use in polymer fields such as plastics, rubber, chemical fibre, coating and polymer builders.AB block copolymer both is different from A because of containing two kinds of segmented structure that performance is different simultaneously, showing, and also is different from the characteristic of B, has expanded the range of application of product greatly.The di-block copolymer that polyvinyl acetate (PVA) and other monomer form is exactly the interested polymkeric substance of class people, and existing synthetic method has following several:
1. document Liu, Futian; Cao, Shuqin, J.Appl.Polym.Sci.48 (3), 425-434 (1993) has reported a kind of elder generation and has regulated the polystyrene low-grade polymer that monomer polymerization such as vinylbenzene obtains holding sulfydryl with sulfocompound, regulates the polystyrene-poly vinyl acetate di-block copolymer that the vinyl acetate between to for plastic polyisocyanate polyaddition obtains sulfur-bearing with this end sulfydryl polymkeric substance again.This method side reaction is many, the system complexity.
2. Japanese Patent JP 01,174, and 513 disclose the initiator that a kind of usefulness has two peroxy-radicals, causes the method for the di-block copolymer of the synthetic polyvinyl acetate (PVA) of different monomers and other alkene monomer polymer composition under two different temperature.The junction that this segmented copolymer is two sections is the initiator fragment, and two end groups are uncertain groups.This method exists side reaction many too, forms complexity, the shortcoming that molecular weight distribution is very wide.
3. document Mardare, Deniela; Malyjaszewski, Krzysztof, Polym.Prep.34 (2), 566-7 (1993) has reported a kind of method of making catalyst to synthesize vinyl acetate between to for plastic ester block copolymer with trialkylaluminium etc., two non-chlorine substituents of end group of synthetic segmented copolymer, two sections junction is a random copolymerization segment.This system is too complicated, and side reaction is more, and agents useful for same very easily fires explosive.
4. document M.Destarac, J.M.Bessiere, Bouteven, polym.preprins.38 (1), 677-8 (1997) mentions a kind of redox telomerization, can synthesizing vinyl acetate ester-styrene block copolymer, but the molecular weight of the A section of this AB block copolymer is less than 700, and be not with the chlorine atom, do not have clear and definite molecular weight and molecular weight distribution data.
The objective of the invention is to overcome the deficiencies in the prior art, a kind of synthetic novel method that contains the AB type di-block copolymer of polyvinyl acetate (PVA) is provided, wherein the A section is a polyvinyl acetate (PVA), and the B section is the polymkeric substance of polystyrene or poly-(methyl) vinylformic acid (ester).This method have reaction conditions gentleness, suitable monomers extensively, the length of two sections of resulting polymers clear in structure, A, B, the advantage that ratio can be regulated, molecular weight distribution is narrower.
Design of the present invention is such:
Vinyl acetate, tetracol phenixin, radical initiator, solvent are placed reactor, it is trichloromethyl that reaction generates an end, the other end is the prepolymer of a chlorine atom, allow prepolymer in the presence of catalyzer, cause vinylbenzene or (methyl) vinylformic acid monomer polymerizations such as (esters), just obtain two ends respectively with the AB block copolymer of a chlorine atom, the tie point of A and B is a saturated carbon atom that contains two chlorine atoms.
The present invention realizes according to such design:
Place reactor to react Vinyl Acetate Monomer, tetracol phenixin, solvent 1 (also not solubilizing agent), radical initiator, the material of gained dissolves with solvent 1, with precipitation agent 1 precipitation, so handle for several times, the oven dry of gained precipitation just obtains prepolymer, place reactor to react prepolymer, catalyzer, vinyl monomer, solvent 2 (or not solubilizing agent), after the gained material dissolves with solvent 2, with precipitation agent 2 precipitations, so handle for several times, the oven dry of gained precipitation promptly gets AB block copolymer of the present invention.
Described solvent 1 is methyl alcohol, ethanol, butanols, acetone, butanone, acetate esters, tetrahydrofuran (THF), dioxane, benzene and alkyl substituent thereof.
Described precipitation agent 1 is the mixture of water, sherwood oil or they and solvent 1.
Described catalyzer is the title complex of CuCl, CuBr and bipyridine or its alkyl substituent.
Described solvent 2 is benzene and alkyl substituent thereof, tetrahydrofuran (THF), dioxane, phenyl ether, methyl-phenoxide, acetate esters, acetone, butanone, N, dinethylformamide.
Described precipitation agent 2 is the mixture that methyl alcohol, ethanol, glycerine, water, methanol, ethanol/water, glycerin/water, sherwood oil or they and solvent 2 are formed.
The molecular weight of described prepolymer is 1000～60000, chlorine atom of an end band of prepolymer, the other end has a trichloromethyl, its structure be Cl-(VAc-)
n-CCl
3VAc represents vinyl acetate.
Described vinyl monomer is vinylbenzene, (methyl) vinylformic acid (ester)
The A section of described AB block copolymer is a polyvinyl acetate (PVA), and molecular weight is 1000～60000; The B section is a vinylbenzene, the polymkeric substance that (methyl) vinylformic acid (ester) monomer forms, and the molecular weight of B section is 500～90000; The molecular weight of AB block copolymer is 2000～150000; The tie point of A and B is a saturated carbon atom that contains two chlorine atoms, and two end groups respectively are with a chlorine atom, and its structural formula is: Cl-(VAc-)
n-CCl
2-(M-)
m-Cl, M represent vinylbenzene or (methyl) vinylformic acid (ester).
The synthetic technological condition of AB block copolymer is such:
With Vinyl Acetate Monomer, tetracol phenixin, solvent 1, radical initiator places reactor, go out intrasystem air with nitrogen or argon replaces, stir down and (be generally 1～10 hour) more than 0.5 hour in 30～110 ℃ of reactions, cooling back material dissolves with solvent 1, with precipitation agent 1 precipitation, so handle for several times, oven dry just obtains performed polymer, with it and catalyzer, vinyl monomer, solvent 2 (or not solubilizing agent) places reactor, stir down and (be generally 2～48 hours) more than 0.5 hour in 30～140 ℃ of reactions, after product dissolves with solvent 2, with precipitation agent 2 precipitations, the precipitation repeated treatments is dried and is promptly got AB block copolymer of the present invention for several times.
The synthetic of the di-block copolymer of polyvinyl acetate (PVA) is difficult, especially the AB block copolymer that has above constitutional features is more difficult synthetic, in the existing synthetic method, no matter be to regulate polymerization with the organism of sulfur-bearing, still under differing temps, cause two kinds of monomer polymerizations with dual functional superoxide, all produce a lot of side reactions inevitably, the molecular weight size of segmented copolymer is difficult to control, troublesome poeration.Alkyl aluminum system is very complicated, and aluminum alkyls very easily burns, explodes, and in the AB block copolymer that this method obtains, A, B connection portion are clear inadequately, and the molecular weight of AB segmented copolymer is lower.The A segment molecule amount of redox telomerization method synthetic AB block copolymer is too little, and the AB segmented copolymer does not have clear and definite molecular weight and molecular weight distribution data.Have only a carbon atom that contains two chlorine atoms to connect between resulting AB block copolymer A of the present invention and the B, respectively there is a chlorine atom that is convertible into other functional group at two ends, the molecular weight of A section is bigger, shared large percentage in AB block copolymer can fully demonstrate the character of polyvinyl acetate (PVA).Suitable monomers of the present invention is extensive, and the structure of the segmented copolymer that obtains is distinct.The molecular weight of A section and B segment molecule amount and AB can be regulated as required.Therefore, utilize the present invention can synthesize other method and be difficult to the very useful AB type Vinyl Acetate Copolymer ester block copolymer of synthetic one class, the reaction conditions gentleness, reagent is easy to get, and working method is simple and easy to do, is easy to industrialization.
Embodiment one
In the reaction flask that has condenser, agitator, logical nitrogen conduit, add the VAc monomer after 45ml makes with extra care, the 2ml tetracol phenixin, 0.0747 the AIBN of gram, the air in the logical nitrogen replacement bottle 15 minutes stirs and is warming up to 60 ℃, insulation reaction 120 minutes, be cooled to room temperature, add 40ml methyl alcohol, after stirring, slowly pour in the 200ml water, precipitation washes with water, repeated treatments three times, and 50 ℃ of vacuum dryings got prepolymer 34 grams in 8 hours.The GPC gel chromatography records Mn=3088, take by weighing prepolymer 1.000 grams, cuprous chloride 0.0449 gram, 2,2 '-bipyridine 1.669 restrains in reactor, injects 5ml butyl methacrylate, 5ml butylacetate with syringe, stirring makes the prepolymer dissolving,-20 ℃ of vacuum nitrogen filling gas three times, sealed reactor was in 125 ℃ of reactions 24 hours, product dissolves with tetrahydrofuran (THF), with methanol extraction three times, precipitation is prior to 50 ℃ of oven dry 2 hours, again in 50 ℃ of following vacuum dryings 8 hours, get prepolymer 4.91 grams, transformation efficiency 87% contains vinyl acetate and two kinds of segments of butyl methacrylate through the Infrared spectroscopy proof, and what therefore obtain is the PVAc-b-PBMA segmented copolymer, it is Mn=18042 that the GPC gel chromatography records molecular weight, molecular weight distribution coefficient Mw/Mn=1.27.
Embodiment two
In the reaction flask that has condenser, agitator, logical nitrogen conduit, add the VAc monomer after 45ml makes with extra care, the 2ml tetracol phenixin, 0.0747 the AIBN of gram, the air in the logical nitrogen replacement bottle 15 minutes stirs and is warming up to 60 ℃, insulation reaction 120 minutes is cooled to room temperature, adds 40ml methyl alcohol, after stirring, slowly pour in the 200ml water, precipitation washes with water, repeated treatments three times, precipitation got prepolymer 34 grams in 8 hours in 50 ℃ of vacuum dryings again prior to 50 ℃ of oven dry 2 hours.The GPC gel chromatography records Mn=3088, take by weighing prepolymer 1.006 grams, cuprous chloride 0.0420 gram, 2,2 '-bipyridine 0.1675 restrains in reactor, injects 5ml methyl methacrylate, 5ml dimethylbenzene with syringe, stirring makes the prepolymer dissolving,-20 ℃ of vacuum nitrogen filling gas three times, sealed reactor was in 130 ℃ of reactions 24 hours, product dissolves with tetrahydrofuran (THF), with methanol extraction three times, precipitation is prior to 50 ℃ of oven dry 2 hours, again in 50 ℃ of following vacuum dryings 8 hours, get product 5.020 grams, transformation efficiency 89.3%.Contain vinyl acetate and two kinds of segments of methyl methacrylate through the Infrared spectroscopy proof, what therefore obtain is the PVAc-b-PMMA segmented copolymer, and it is Mn=16801 that the GPC gel chromatography records molecular weight, molecular weight distribution coefficient Mw/Mn=1.27.
Embodiment three
In the reaction flask that has condenser, agitator, logical nitrogen conduit, add the VAc monomer after 45ml makes with extra care, 5ml tetracol phenixin, the AIBN of 0.0500 gram, logical N
2Air in the displacement bottle 15 minutes stirs and is warming up to 60 ℃, and insulation reaction 120 minutes is cooled to room temperature, add 40ml methyl alcohol, after stirring, slowly pour in the 200ml water, precipitation washes with water, repeated treatments three times, and 50 ℃ of vacuum dryings got prepolymer 31 grams in 8 hours.The GPC gel chromatography records Mn=1243, take by weighing prepolymer 0.2013 gram, cuprous chloride 0.0153 gram 2,2 '-bipyridine 0.0647 restrains in reactor, inject the 3ml styrene monomer with syringe, the 5ml phenyl ether stirs and to make the prepolymer dissolving ,-20 ℃ of vacuum nitrogen filling gas three times, sealed reactor, in 120 ℃ of reactions 24 hours, product dissolved with tetrahydrofuran (THF), used methanol extraction three times, precipitation was prior to 50 ℃ of oven dry 2 hours, again in 50 ℃ of following vacuum dryings 8 hours, product 1.16 grams, transformation efficiency 66%, contain vinyl acetate and two kinds of segments of vinylbenzene through the Infrared spectroscopy proof, what therefore obtain is the PVAc-b-PSt segmented copolymer, and it is Mn=7014 that the GPC gel chromatography records molecular weight, molecular weight distribution coefficient Mw/Mn=1.23.
Embodiment four
In the reaction flask that has condenser, agitator, logical nitrogen conduit, add the VAc monomer after 45ml makes with extra care, 5ml tetracol phenixin, the AIBN of 0.0500 gram, logical N
2Air in the displacement bottle 15 minutes stirs and is warming up to 60 ℃, and insulation reaction 120 minutes is cooled to room temperature, add 40ml methyl alcohol, after stirring, slowly pour in the 200ml water, precipitation washes with water, repeated treatments three times, and 50 ℃ of vacuum dryings got prepolymer 31 grams in 8 hours.The GPC gel chromatography records Mn=1243, take by weighing prepolymer 0.2300 gram, cuprous chloride 0.0164 gram, 2,2 '-bipyridine 0.0666 restrains in reactor, inject the 3ml methyl methacrylate with syringe, 3ml dimethylbenzene stirs and makes the prepolymer dissolving,-20 ℃ of vacuum nitrogen filling gas three times, sealed reactor was in 130 ℃ of reactions 20 hours, product dissolves with tetrahydrofuran (THF), uses methanol extraction three times, precipitation was prior to 50 ℃ of oven dry 2 hours, again in 50 ℃ of following vacuum dryings 8 hours, product 2.684 grams, transformation efficiency 90%, contain vinyl acetate and two kinds of segments of methyl methacrylate through the Infrared spectroscopy proof, what therefore obtain is the PVAc-b-PMMA segmented copolymer, and it is Mn=15600 that the GPC gel chromatography records molecular weight, molecular weight distribution coefficient Mw/Mn=1.20.
Embodiment five
In the reaction flask that has condenser, agitator, logical nitrogen conduit, add the VAc monomer after 45ml makes with extra care, 1ml tetracol phenixin, the AIBN of 0.050 gram, logical N
2Air in the displacement bottle 15 minutes, stirring is warming up to 60 ℃, insulation reaction 120 minutes is cooled to room temperature, adds 40ml methyl alcohol, after stirring, slowly pour in the 200ml sherwood oil precipitation petroleum ether, repeated treatments three times into, precipitation got prepolymer 26 grams in 8 hours in 50 ℃ of vacuum dryings again prior to 50 ℃ of oven dry 2 hours.The GPC gel chromatography records Mn=58700, take by weighing prepolymer 3.110 grams, cuprous chloride 0.0051 gram, 2,2 '-bipyridine 0.0254 restrains in reactor, injects 5ml vinylbenzene, 5ml dimethylbenzene with syringe, stirring makes the prepolymer dissolving,-20 ℃ of vacuum nitrogen filling gas three times, sealed reactor was in 130 ℃ of reactions 19 hours, product dissolves with tetrahydrofuran (THF), with methanol extraction three times, precipitation is prior to 50 ℃ of oven dry 2 hours, again in 50 ℃ of following vacuum dryings 8 hours, get product 4.33 grams, transformation efficiency 30%.Contain vinyl acetate and two kinds of segments of vinylbenzene through the Infrared spectroscopy proof, what therefore obtain is the PVAc-b-PSt segmented copolymer, and it is Mn=81200 that the GPC gel chromatography records molecular weight, molecular weight distribution coefficient Mw/Mn=1.54.
Claims (8)
1. the AB block copolymer of AB block copolymer synthetic method and preparation thereof, it is characterized in that: vinyl acetate (VAc), tetracol phenixin, radical initiator place reactor, reaction forms prepolymer, then prepolymer, catalyzer, vinyl monomer (M) are placed reactor, reaction forms AB block copolymer of the present invention under nitrogen or argon gas atmosphere.
2. method according to claim 1 is characterized in that employed radical initiator is an azo type free base initiator.
3. method according to claim 1, the constitutional features that it is characterized in that prepolymer are linear polyvinyl acetate (PVA), and in two end group, one is trichloromethyl, and another is the chlorine replacing group, its structure be Cl-(VAc-)-
nCCl
3
4. method according to claim 1, the synthesis temperature of prepolymer are 30～110 ℃.
5. method according to claim 1 is characterized in that employed catalyzer is CuCl, CuBr and 2, the title complex that 2 '-bipyridine and alkyl substituent thereof form.
6. method according to claim 1 is characterized in that used vinyl monomer is vinylbenzene, (methyl) vinylformic acid (ester).
7. method according to claim 1, the temperature of reaction that it is characterized in that adding behind catalyzer, monomer, the solvent is 30～140 ℃.
8. method according to claim 1, it is characterized in that the synthetic AB of institute type block polymer has following constitutional features: (a) in the AB block copolymer, connecting A and B two segmental nodes is saturated carbon atoms that contain two chlorine atoms, a chlorine atom respectively is with at two ends, its structure be Cl-(VAc-)-
nCCl
2-(M-)-
mCl; (b) the A section of AB block copolymer is a polyvinyl acetate (PVA), and A segment molecule amount is 1000～60000; (c) the B section of AB block copolymer is polystyrene, poly-(methyl) vinylformic acid (ester) class, and molecular weight is 500～90000; (d) molecular weight of AB block copolymer is 2000～150000.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1293262C (en) * | 2003-07-16 | 2007-01-03 | 气体产品聚合物公司 | Polymer emulsion coatings for cellulosic substrates with improved barrier properties |
| CN101864050A (en) * | 2010-06-29 | 2010-10-20 | 上海东升新材料有限公司 | High-efficiency salt-tolerance dispersing agent and preparation method and application thereof |
| CN105566587A (en) * | 2016-02-17 | 2016-05-11 | 青岛大学 | Preparation method and application of polyvinyl alcohol diazo polymer |
-
1997
- 1997-07-10 CN CN 97106509 patent/CN1205341A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1293262C (en) * | 2003-07-16 | 2007-01-03 | 气体产品聚合物公司 | Polymer emulsion coatings for cellulosic substrates with improved barrier properties |
| US7427444B2 (en) | 2003-07-16 | 2008-09-23 | Air Products Polymers, L.P. | Polymer emulsion coatings for cellulosic substrates with improved barrier properties |
| CN101864050A (en) * | 2010-06-29 | 2010-10-20 | 上海东升新材料有限公司 | High-efficiency salt-tolerance dispersing agent and preparation method and application thereof |
| CN101864050B (en) * | 2010-06-29 | 2012-11-28 | 上海东升新材料有限公司 | High-efficiency salt-tolerance dispersing agent and preparation method and application thereof |
| CN105566587A (en) * | 2016-02-17 | 2016-05-11 | 青岛大学 | Preparation method and application of polyvinyl alcohol diazo polymer |
| CN105566587B (en) * | 2016-02-17 | 2018-03-30 | 青岛大学 | A kind of preparation method and applications of polyvinyl alcohol diazonium polymer |
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