CA2108860C - Cyclopentadienyl group 6b alpha-olefin polymerization catalysts and process for polymerizing alpha-olefins - Google Patents

Abstract

Disclosed is a catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal hydrocarbyl compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support. The catalyst system may also contain a Group 2 or Group 3 metal alkyl compound.

Description

21 088 fi0 Ol CYCLOPENTADIENYL GROUP 6b METAL ALPHA-OLEFIN POLYMERIZATION
OZ CATALYSTS AND PROCESS FOR POLYMERIZING ALPHA-OLEFINS

FIELD OF THE INVENTION
os 06 The present invention relates to catalyst systems for 09 polymerizing alpha-olefins and processes for polymerizing 08 alpha-olefins using such catalysts.

aACKGROUND OF THE INVENTION

is Chromium based catalysts are used in the commercial 13 polymerization of small alpha-olefins such as ethylene and l~ propylene. One such catalyst is prepared by depositing is chromocene (bis(cyclopentadienyl) chromium (II)) on an 16 inorganic metal oxide support, as disclosed in British 17 Patent No. 1,253,063 to Karapinka. U.S. Patent 18 No. 4,015,059, issued March 29, 1977 to Rarol, describes the 19 use of bis(indenyl)- and bis(flourenyl)-chromium (II) ZO compounds supported on activated inorganic oxide supports as Zl catalysts for the polymerization of ethylene.

Z3 Recently, new synthetic methods have been described for Z~ preparing Cr+3 organometallic compounds. Theopold, J.J. Am.
Z5 Chew. Soc. (1988), ~Q, 5902 entitled "Cationic Chromium 26 (III) Alkyls as Olefin Polymerization Catalysts", Theopold, Z7 Acc. Chem. Res. (1990), ~, 263 entitled "Organochromium Z8 (III) Chemistry: A Neglected Oxidation State" and Thomas Z9 et al., J. Amer. Chem. Soc., ~ (1991), p. 893 et seq.
30 disclose that certain pentamethylcyclopentadienyl chromium 31 (III) alkyls can be prepared, and that they can be used for 3Z making polyethylene homogeneously in CHzCl2. However, these 33 homogeneous Cr (III) polymerization catalysts have several 3 ~1 2~ 088 so 01 deficiencies. These include low polymer productivity, rapid OZ deactivation, and the need to use polar, non-coordinating 03 solvents. Additionally, since they are homogeneous catalysts, they are unsuitable for gas phase olefin 05 polymerizationa.

07 U.S. Patent No. 4,530,914, issued July 23,1985 to Ewen 08 et al., discloses a catalyst system for the polymerization 09 of alpha-olefins which comprises two or more metallocenea, each having different propagation and termination rate 11 constants, and aluminoxane. The metallocenee are iZ cyclopentadienyl derivatives of a transition metal of 13 Group 4b, 5b, and 6b metals of the Periodic Table. They are described by the formulas ( CsR' m) pR", (CsR' m) MeQ~ and R"s(CSR~m)2MeQ' where (CSR'm) is a cyclopentadienyl or 16 s~atituted cyclopentadienyl, each R' is hydrogen or a 17 hydrocarbyl radical, R" is an alkylene radical, a dialkyl i8 germanium or silicon or an alkyl phosphine or amine radical i9 bridging two (CsR'm) rings, Q is a hydrocarbon radical, Me ZO is a Group 4b, 5b, or 6b metal, a is 0 or 1, p is 0, 1, Z1 or 2; when p=0, s=0; m is 4 when s is 1 and m is 5 when a ZZ is 0.

U.S. Patent No. 4,939,217, issued July 3, 1990 to Stricklen, Z5 also discloses a process for polymerizing olefins where the Z6 polymerization is conducted in the presence of hydrogen, and Z7 a catalyst system is used which contains aluminoxane and at Z8 least two metallocenea, each having different olefin 29 polymerization ten~nination rate coastanta. The metallocenes 30 disclosed are similar to those described in aforementioned 31 U,S. Patent No. 4,530,914.

01 U.S. Patent No. 4,975,403, issued December 4, 1990 to Ewen, OZ discloses a catalyst system for use in the polymerization of 03 olefins. The catalyst system includes at least two Os different chiral, stereo-rigid metallocene catalysts of the OS formula R~~(Cs(R~)4)2MeQp (where Me is a Group 4b, 5b or 6b 06 metal and (CS(R~)4) is a cyclopentadienyl or substituted cyclopentadienyl ring) and an aluminum compound.

09 Canadian Patent Application No. 2,000,567, published April 13, 1990, discloses a process for producing 11 polyethylene using a composite catalyst made up of a solid iZ catalyst component typified by a selected chromium compound, 13 a modified aluminum compound typified by a trialkylaluminum, 1~ and an alkylaluminum alkoxide compound. The chromium compound may be chromium oxide, and the modified aluminum 16 compound may be the reaction product of an organoaluminum compound and water.

i9 It has now been discovered that when cyclopentadienyl ZO Group 6b metal hydrocarbyl compounds, in which the Group 6b Z1 metal is in an oxidation state of +3, are supported on ZZ inorganic metal oxide or inorganic metal phosphate supports, Z3 high productivity alpha-olefin polymerization catalysts are Z'~ produced, sad that the use of a co-catalyst improves the Z5 productivity of many of these compounds.

SU1~ARY OP TfIB INVENTION

Z9 In accordance with the present invention, there is provided 30 a catalyst system for the~homopolymerization and 31 copolymerization of alpha-olefins having 2-8 carbon atoms, 3Z said catalyst system comprising a cyclopentadienyl Group 6b 33 metal hydrocarbyl compound in which the metal has an 3~

21 oss s o 01 cxidation state of +3, said Group 6b metal compound being OZ supported on an inorganic support.

There is also provided in accordance with the present 05 invention a catalyst system for the homopolymerization and 06 copolymerization.of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b 08 metal hydrocarbyl compound in which the metal has an O9 oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, and a Group 2 or 3 metal 11 alkyl compound.
iZ
13 Further provided in accordance with the present invention is a process for the homopolymerization or copolymerization of alpha-olefins having 2-8 carbon atoms comprising 16 polymerizing said alpha-olefin, or copolymerizing two or 1~ more alpha-olefins in the presence of a catalyst system 18 comprising a cyclopentadienyl Group 6b metal hydrocarbyl i9 compound in which the metal has an oxidation state of +3, ZO said group 6b metal compound being supported on an inorganic Z1 support.
ZZ
Z3 The present invention also provides a process for the Z~ homopolymerization or copolymerization of alpha-olefins Z5 comprising polymerizing said alpha-olefin, or copolymerizing Z6 two or more alpha-olefins in the presence of a catalyst Z~ system comprising a cyclopentadienyl Group 6b metal Z8 hydrocarbyl compound in which the metal has an oxidation Z9 state of +3, said group 6b metal compound being supported on 30 an inorganic support, and a Group 2 or 3 metal alkyl 31 compound.
3~
33 In the above catalyst systems and processes, chromium is a preferred Group 6b metal, silica, aluminum phosphate and alumina aluminum phosphate are preferred supports, and aluminoxanes and trialkylaluminum compounds are preferred 5 Group 2 or 3 metal alkyl compounds.
According to one aspect of the invention there is provided a catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, wherein the chromium compound is selected from Cp*Cr (CH3) 2 (DMAP) Cp*Cr(CH3)z(PMezPh) Cp*Cr(CH3)2(3,5-lutidine) CpCr ( CH3 ) 3 ( PMe2Ph ) CpCr(CH3)2(DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl.
In accordance with another aspect of the invention there is provided a catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, and a Group 2 or 3 metal alkyl compound, wherein the Group 6b metal compound is selected from 5a Cp*Cr (CH3) 2 (DMAP) Cp*Cr(CH3)z(PMe2Ph) Cp*Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr ( CH3 ) 2 ( DMAP ) wherein Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl and wherein the molar ratio of said metal alkyl compound to said chromium compound is about 1:1 to 1000:1.
In accordance with a further aspect of the invention there is provided a process for the homopolymerization or copolymerization of alpha-olefins having 2-8 carbon atoms comprising polymerizing said alpha-olefin, or copolymerizir~g two or more alpha-olefins in the presence of a catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, wherein the Group 6b metal compound is selected from Cp*Cr (CH3) 2 (DMAP) Cp*Cr (CH3) 2 (PMe2Ph) Cp*Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl.

5b In accordance with yet another aspect of the invention there is provided a process for the homopolymerization or copolymerization of alpha-olefins comprising polymerizing said alpha-olefin, or copolymerizing two or more alpha-olefins in the presence of a catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, and a Group 2 or 3 metal alkyl compound, wherein the Group 6b metal compound is selected from Cp*Cr(CH3)2(DMAP) Cp*Cr(CH3)2(PMe2Ph) Cp*Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl and wherein the molar ratio of said metal alkyl compound to said chromium compound is about 1:1 to 1000:1.
BRIEF DESCRIPTION OF THE FIGURES
Figures 1, 2 and 3 each show scanning electron micrographs of polyethylene samples.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention provides catalyst systems for use in the polymerization (either homopolymerization or copolymerization) of alpha-olefins, including ethylene, propylene, 1-butene, 1-hexene and 4-methyl-1-pentene 5c It has quite surprisingly been found that, even though the productivity of many cyclopentadienyl Group 6b metal hydrocarbyl. compounds is quite low when employed as catalyst in the homogeneous polymerization of alpha-olefins, when these compounds are supported on an inorganic metal oxide or inorganic phosphate solid support, their.productivity increases dramatically, especially when co-catalysts are used. While the catalyst systems of the present invention can be used to polymerize a variety of alpha-olefins, they are especially useful in the polymerization of ethylene.
These catalysts produce polyethylene in high yield, and the polymers produced have remarkably uniform particle size and highly desirable morphology (i.e., substantially spherical) that is suitable for gas phase polymerizations. The catalysts of the present invention allow the use of hydrogen during polymerization of polyethylene to reduce the molecular weight and to broaden the molecular weight distribution. In addition, the catalyst systems of this 01 invention produce polyethylene with a variety of molecular OZ weight distributions, depending on the support used.

Referring now to the Figures, Figure 1 shows a scanning 05 electron micrograph (S8M) at X10 magnification of a 06 polyethylene sample produced by homogeneous polymerization using [Cp*Cr (THF) 2CH3] + [HPh4] ' (where Cp* represents 08 pentamethylcyclopentadienyl, THF is tetrahydrofuran, and Ph O9 is phenyl). As can be seen, this sample is characterized by very small, irregularly shaped particles. These particles 11 are typically less than 20-50 ~cm (microns) in diameter.
is Figure 2 shows an SEM at X10 magnification of a polyethylene 13 s~ple produced by the method of the present invention using 1'~ Cp*Cr (CFi3) 2 (TIiF) on a silica support. As can be seen, this s~ple has particles of much larger size (about 1 mm in 16 diameter) than those in Figure 1. The particle size is 1~ quite suitable for gas phase polymerization applications.
18 Figure 3 shows a SBri of a polyethylene sample produced by i9 the method of this invention using Cp*Cr(CH3)Z(TIiF) on a ZO A1243~2A1P04 support. As can be seen, the particles are Z1 quite uniform in size, and primarily spherical in nature.
ZZ Again, the particle size and spherical nature of the polymer Z3 makes this s stem attractive for 2~ Y gas phase polymerization applications.

Z6 Activities for the catalyst systems of the present invention are greater than 3,000 grams of of Z8 metal er hour (" /g Cr/hr~), p her pe gram of chromium P 9 preferably greater than 29 30,000 g/g Cr/hr, and more preferably greater than 30 200,000 g/g Cr/hr.

32 The term molecular weight distribution (~MWD"), as used 33 herein, is the weight average molecular weight ("1~"") 3~

2~ oss so 01 divided by the number average molecular weight (~I~~), i.e., OZ 1~",/I~". The polymers produced in accordance with the present 03 invention using silica supported catalysts have a MWD
greater than 10, preferably greater than 15, and more 05 preferably greater than 20. These polymers, which have high 06 ~~9, have improved ease of processing, better melt behavior, and other desirable properties such as impact O8 resistance and environmental stress crack resistance. Large 09 blow molded products are superior when made with high MWD
polymers. Additionally, film is more puncture resistant 11 when made from polymer with a high MWD. The polymers made iZ in accordance with this invention using alumina aluminum 13 phosphate supported catalysts possess high molecular weight 1'~ and a more narrow MWD, making them useful in such applications as injection molding. Typically, the MWD for 16 polymers made with alumina aluminum phosphate supported 1~ catalysts is less than 3.

19 ~e catalyst systems of the present invention comprise at ZO least one cyclopentadienyl Group 6b metal hydrocarbyl Z1 compound in which the Group 6b metal is in an oxidation Z2 state of +3, and which is catalytically active when Z3 deposited oa as inorganic metal oxide or inorganic metal Z~ phosphate support. As used herein, the term Z5 ~cyclopentadienyl~ refers to unsubstituted cyclopentadienyl Z6 as well ae substituted derivatives of cyclopentadienyl in Z~ which the cyclopentadienyl ring coatains one or more Z8 substituents which do not interfere with the Group 6b metal Z9 compound's ability to function as an alpha-olefin 30 polymerization catalyst. Bxamples of substituted 31 cyclopentadienyl include pentamethylcyclopentadienyl, 3Z methylcyclopentadienyl, t-butylcyclopentadienyl, and 33 pentaphenylcyclopentadienyl, as well ae compounds where the 01 substituent forms a multi-cyclic riag with the OZ cyclopentadienyl ring. Examples of these multi-cyclic rings 03 include indenyl and fluorenyl rings. For the sake of simplicity, the abbreviation ~Cp~ will be used herein to 05 refer to unsubstituted cyclopentadienyl, and the 06 abbreviation ~Cp*~ will be used to refer to pentamethylcyclopentadienyl. Cp* is a preferred 08 cyclopentadienyl group as it stabilizes the organometallic 09 compound of this invention.
11 The Group 6b metal compounds useful ia.the present invention is include compounds wherein the metal is chromium, molybdenum 13 or tungsten. Compounds in which the metal is chromium are 1~ preferred. The Group 6b metal atom is the compound has an oxidation state of +3.

1~ These Group 6b metal compounds have, in addition to one 18 cyclopentadienyl group, at least one hydrocarbyl group i9 bonded to the metal atom. Ae used herein, the term ZO "hydrocarbyl~ refers to alkyl, alkeayl, aryl, aralkyl and Z1 alkaryl radicals and the like. Exemplary hydrocarbyl ZZ radicals include, but are not limited to, methyl, ethyl, Z3 propyl, butyl, amyl, isoamyl, hexyl, aeopentyl, isobutyl, Z~ heptyl, octyl, aonyl, decyl, cetyl, phenyl, benzyl and other Z5 similar groups. Additionally, organosilyl groups, such as Z6 trimethyleilyl methyl, i.e., (CI~)3SiCFh-, and the like can Z~ be used. If more than one hydrocarbyl group is bonded to Z8 the metal atom, they can be independent or linked, i.e., Z9 they can form a 3-, 4-, 5-, 6-, or 7-mrembered metallocycle.
30 preferably, the hydrocarbyl group is sigma bonded to the 31 Group 6b metal.

33 In addition to the cyclopentadienyl sad hydrocarbyl groups, 3S the Group 6b metal compounds of the present invention may _g_ 01 also contain one or more sigma donor stabilizing ligands.
OZ These liganda contain an atom, such as oxygen, nitrogen, 03 phosphorous or sulfur, which has a nonbonded electron pair.
0! Examples of these ligands include, but are not limited to, 05 ethers, amines, phosphines and thioethers. Ethers such as 06 tetrahydrofuran fTHF) and amines such as pyridine are 07 preferred. Compounds with pyridine are moat preferred and O8 give catalysts With high activity and stability.

E~camples of the Group 6b metal compounds useful in this 11 invention include, but are not limited to, compounds haviag is the following general formulas:

1! (CS(R')s)~L (I) t (Cs(R~ )s),1~DC~,1~ (II) or 16 . t (Cs fR' ) s),I~Cb (L) m] + [A)' (III) 18 wherein M is a Group 6b metal such as chromium, molybdenum 19 and tungsten;
ZO
Z1 (CS(R~)s) is a cyclopentadienyl or substituted ZZ cyclopentadienyl ring;

Z! R' is at each independent occurrence hydrogen, a hydrocarbyl Z5 radical having 1-20 carbon atoms, or adjacent R' groups may Z6 together form one or more rings;

Z8 X is a hydrocarbyl radical having 1-20 carbon atoms (for Z9 example, a monovalent saturated aliphatic or alicyclic 30 radical or a monovalent aromatic radical, or combinations 31 thereof);

33 a ~ 1 or 2 , b - I or 2 where a+b ~ 3 ;
3!

01 c = 1 or 2 with the proviso that when c = 2 then X is alkyl;
OZ
03 L is at each independent occurrence a sigma donor stabilizing ligand;

06 m = 1 to 2 inclusive; and OS A is an anion.

Fac~ples of compounds having Formula (I) above include, but 11 are not limited to, Cp*Cr (CFI3) 2 (TFIF) , Cp*Cr (Hzyl ) 2 (THF) , iZ Cp*Cr (Hzyl)2(Pyr), Cp*Cr(CFi3)Z(Pyr), Cp*Cr(TMSSM)2(Pyr), 13 Cp*Cr (TMSM) 2, Cp*Cr (CH3) 2 (DMAP) , Cp*Cr (CFI3) 2 (PMezPh) , 1~ Cp*Cr(CH3)2(3,5-Lutidine), and CpCr(CH3)2(DMAP), where Hzyl is benzyl, Pyr is pyridine, TMSM is trimethylsilylmethyl, 16 Dip is N,N-dimethylaminopyridine, and PMe2Ph is 17 dimethylphenylphosphine.

19 ~rther examples of the Grou 6b c p ompounds of this invention ZO include monomeric Grou 6b metal c Z1 P ompounds, dimeric Group 6b metal compounds, and cationic Group 6b metal compounds. A
preferred moaomeric Group 6b metal compound is ~3 Cp*Cr (Hzyl) 2 (TIiF) , [Cp*Cr (CH ) ] is a Z~ 3 2 2 Preferred dimeric ~5 compound, and a preferred cationic compound is [Cp*CrCIi3 (TFIF)2] + (HPh~]'. Especially preferred compounds are C~*Cr(CIi3)Z(Pyr), Cp*Cr(CFI3)2(3,5-Lutidine) and ~8 Cp*Cr (CH3) 2 (PMe2Ph) .

30 In Part, the choice of Group 6b metal compound is based on 31 the thernial stability of the compound and its ease of preparation. Of the Group 6b metal compounds useful in this 33 invention, the organochromium compounds are preferred.
3~

Theopold, J. Am. Chem. Soc. (1988), 110, 5902 entitled "Cationic Chromium (III) Alkyls as Olefin Polymerization Catalysts", Theopold, Acc. Chem. Res. (1990), 23, 263 entitled "Organochromium (III) Chemistry: A Neglected Oxidation State", and Thomas et al., J. Amer. Chem.
Soc.,113 (1991), p. 893 et seq. describe syntheses useful in making some of the Group 6b metal compounds of this invention. Similar procedures can be used to make related compounds.
In the catalyst systems of the present invention, the Group 6b metal compound is deposited on an inorganic support. Suitable inorganic metal oxide supports include silica, alumina, silica-alumina mixtures, thoria, zirconia, magnesium oxide and similar oxides. Suitable inorganic metal phosphates include aluminum phosphate, zirconium phosphate, magnesium-containing alumina phosphate and alumina aluminum phosphate. Silicas, aluminum phosphates and alumina aluminum phosphates are preferred. Suitable silica supports include Davison 952, Davison 955, Crosfield EP-10 and Crosfield EP17MS.
Further examples of useful supports are the following:
alumina aluminum phosphates with aluminum to phosphorus ratios of about 5:1 to 1:1 as disclosed in U.S. Patents Nos. 4,080,311 and 4,219,444; magnesia-alumina-aluminum phosphates as described in U.S. Patent No. 4,210,560;
zinc oxide-cadmium oxide-alumina-aluminum phosphates such as those disclosed in U.S. Patent No. 4,367,067; and the calcium, barium, and/or strontium oxide-alumina-aluminum phosphates described in U.S. Patent Nos. 4,382,877 and 4,382,878. The acidity of these supports can be adjusted by judicious inclusion of basic metals such as alkali and alkaline earth metals (Ca, Be, Mg, K, Li) to counteract excessive acidity. Other useful supports include magnesium halides, particularly magnesium chloride, such as 01 those described in "Transition Metals and Organometallics as OZ Catalysts for Olefin Polymerization" (1988, Springer-Verlag) 03 edited by W. Raminsky and H. Sinn and "Transition Metal 0! Catalyzed Polymerizationa-Ziegler-Natta and Metathesis 05 polymerizations" (1988, Cambridge University Press) edited 06 by R. Quirk.

08 The supports useful in this invention should have a high Og surface area. In general, these supports should have the characteristics listed in the following table:
11 Proper Broad Rang,~,_ preferred Ranae 12 Surface area 25-600 m2/g 100-370 m2/g 1! Pore volume 0.25-4 cm3/g 0.7-3 car3/g Mean particle 30-200 microns 60-140 microns 16 diameter 18 preferably, the pore size distribution is broad, with a lg significant percentage of the pores in the macropore range ZO 0500 Angstroms). Preferably, at least SO~r of the pores are Z1 macropores. It is also desirable that the support be ZZ substantially anhydrous before the Group 6b metal c~npound Z3 is deposited on it. Thus, it is desirable to calcine the z! support prior to deposition of the Group 6b metal compound.
zs Z6 The supported catalysts of this invention are readily Z7 prepared by techniques well known is the art. For example, Z8 a solution of the Group 6b metal compound in aliphatic, Zg aromatic or cycloaliphatic hydrocarbons, or ethers such as 30 diethyl ether or tetrahydrofuran can be stirred with the 31 support until the Group 6b metal caanpound is adsorbed on or 3Z reacted with the support. The amount of Group 6b metal 33 compound relative to the amount of support will vary 3! considerably depending upon such factors as the particle 01 size of the support, its pore size and surface area, the OZ solubility of the Group 6b metal compound in the solvent 03 employed, and the amount of Group 6b metal compound which is to be deposited on the support. However, in general the 05 amount of Group 6b metal compound used is adjusted so that 06 the final metal content (calculated as the element), relative to the support, is in the range of from about 0.01 08 to about 10 weight percent. In most cases, the most desirable level is in the range of about 0.1 to about 5 weight percent.
ii is It has been found that the activity of many of the supported 13 Group 6b metal compounds of this invention is significantly 1~ increased when they are employed in conjunction with a co-catalyst. The co-catalysts useful in the practice of the 16 present invention are Group 2 and Group 3 metal alkyls. As used herein, the term "Group 2 and Group 3 metal alkyls"
18 refers to compounds containing a metal from Group 2 or i9 Group 3 of the Periodic Table (such as Mg, Zn, H, or Al) to ZO which is bonded at least one alkyl group, preferably a C1 to 21 C8 alkyl group. Suitable Group 2 and Group 3 metal alkyls ZZ include dialkyl magnesium, dialkyl zinc, trialkylboranes, Z3 and aluminum alkyls. Suitable aluminum alkyls include Z~ trialkylaluminums (such as trimethylalumiaum, Zs triethylaluminum, triisobutylaluminum and trioctylaluminum).
Z6 Trialkylaluminums with alkyl groups of four carbons or greater are preferred. Other aluminum alkyls useful in the Z8 practice of the present invention include alkylaluminum Z9 alkoxides (such as diethylaluminum ethoxide and 30 ethylaluminum diethoxide); and alkylaluminum halides (such 31 as diethylaluminum chloride, diethylalua~inum bromide, 3Z diethylaluminum iodide, diethylaluminum fluoride, ethyl 33 aluminum dichloride, ethyl aluminum dibraanide, ethyl 2~ 088 so 01 aluminum diiodide, ethyl aluminum difluoride, and ethyl OZ aluminum sesquichloride).

04 Other suitable aluminum alkyls are aluminoxanes, including 05 those represented by the general formula (R-Al-0)" for the 06 cyclic fozm and R(R-A1-0)o-A1R2 for the linear form. In these formulas, R is, at each independent occurrence, an 08 alkyl group (such as methyl, butyl, isobutyl and the like) 09 preferably with more than two carbon atoms, more preferably with 3-5 carbon atoms, and n is an integer, preferably from 11 1 to about 20. Moat preferably, R is an isobutyl group.
iZ Mixtures of linear and cyclic aluminoxanea may also be used.
13 Eles of aluminoxanes useful is this invention include, 14 but are not limited to, ethyl aluminoxane, ieobutyl aluminoxane, and methyl aluminoxane. Aluminoxanee (also 16 ~o~ as "alumoxanes") suitable for use in this invention 1~ are described in Pasynkiewicz, "Alumoxanee: Synthesis, 18 Structure, Complexes and Reactions," Polyhedron 9, p. 429 i9 (1990), which is incorporated by reference herein in its ZO entirety.

ZZ The preferred Group 2 and Group 3 metal alkyls are the Z3 aluminoxanes and the trialkylaluminums.

Z5 When used, the Group 2 and Group 3 metal alkyls are used in Z6 a Group 2 or 3 metal alkyl to Group 6b metal compound mole Z~ ratio of from about 1:1 to about 1000:1. The preferred mole Z8 ratio is from about 10:1 to about 200:1.

30 ~e catalyst systems of the present invention may be used in 31 either slurry or gas phase polymerization processes. After 3Z the catalysts have been formed, the polymerization reaction 33 is conducted by contacting the monomer charge with a 01 catalytic amount of the catalyst at a temperature and at a OZ pressure sufficient to initiate the polymerization reaction.
03 If desired, an organic solvent may be used as a diluent and Os to facilitate materials handling. The polymerization 05 reaction is carried out at temperatures of from about 30°C
06 or less up to about 200°C or more, depending to a great extent on the operating pressure, the pressure of the entire 08 monomer charge, the particular catalyst being used, and its 09 concentration. Preferably, the temperature ie from about 30°C to about 125°C. The pressure can be any pressure 11 sufficient to initiate the polymerization of the monomer is charge, and can be from atmospheric up to about 1000 psig.
13 As a general rile, a pressure of about 20 to about 800 psig 1~ is preferred.
is 16 When the catalyst is used in a slurry-type process, an inert 1~ solvent medium is used. The solvent should be one which is 18 inert to all other components and products of the reaction i9 system, and be stable at the reaction coaditions being used.
ZO It is not necessary, however, that the inert organic solvent Z1 medium also ses~re as a solvent for the polymer produced.
ZZ The inert organic solvents which may be used include Z3 saturated aliphatic hydrocarbons (such ae hexane, heptane, Z~ pentane, isopentane, isooctane, purified kerosene and the Z5 like), saturated cycloaliphatic hydrocarbons (such ae Z6 cyclohexane, cyclopentane, dimethylcyclopentane, Z~ methylcyclopentane and the like), aromatic hydrocarbons 28 (such ae beazene, toluene, xylene and the like), and Z9 chlorinated hydrocarbons (such as chlorobeazene, 30 tetrachloroethylene, o-dichlorobenzene and the like).
31 particularly preferred solvents are cyclohexane, pentane, 3Z isopentane, hexane and heptane.

3~

When the catalyst is used in a gas phase process, it is suspended in a fluidized bed with, e.g., ethylene.
Temperature, pressure and ethylene flow rates are adjusted so that to maintain acceptable fluidization of the catalyst particles and resultant polymer particles.
Further descriptions of such a fluidized bed may be found in British Patent No. 1,253,063, to Karapinka.
The following examples are intended to further illustrate the present invention.
EXAMPLES

SUPPORTS
Silica supports were purchased from W. R. Grace & Co., and included Davison 952 and Davison 955 silicas. These silicas have the following properties:
Property Davison 952 Davison 955 Surface area 340 m2/g 300 mz/g Pore volume 1.68 cm3/g 1.60 cm3/g Mean particle 110 microns 40 microns diameter Other silica supports were purchased from Crosfield Catalysts. These included EP-10, EP-11 and EP-12 supports. Some properties of the EP-10 support are:
Property Crosfield EP-10 Surface area 320 mz/g Pore volume 1.80 cm3/g Mean particle 105 microns diameter The A1P09 support was purchased from W.R. Grace & Co. The alumina aluminum phosphate supports used in the following examples were prepared by the procedure of Example 1 in U.S. Patent No. 4,080,311, issued March 21, 1978 to Kehl.
The product had an A1z03 to A1P04 ratio of 1:2.
CATALYST PREPARATIONS
In the preparation of the following catalysts, all manipulations were performed under argon using glove box or Schlenk techniques. All solvents were thoroughly dried over Na/benzophenone or calcium hydride and distilled prior to use.

[Cp*Cr (CH3) z] z The organochromium compound [CP*Cr(CH3)z]z was prepared by the procedure described in Theopold, Acc. Chem. Res., 23 (1990), p. 264.

SUPPORTED [Cp*Cr (CH3) z] z The organochromium compound [Cp*Cr(CH3)z]z (0.040 g, 9.2 x 10-5 mole), prepared as described in Example 2, was dissolved in 10 ml of pentane, giving a dark brown solution to which was added Davison 952 silica (1.00 g). The 2~ oss so 01 resulting mixture was stirred for 15 minutes, giving a dark OZ brown solid and a clear supernatant. The resulting solid 03 catalyst was washed with pentane, and dried to a 04 free-flowing powder.

07 SUPPORTED Cp*Cr (CFi3) 2 (THF) [Cp*Cr(CH3)Z]2 (0.040 g, 9.2 x 10-5 mole) was added to 20 ml of tetrahydrofuran (~THF") and stirred for 0.5 hour, ii generating a green colored solution containing iZ Cp*Cr(CH3)2(THF). A1203~2AlPO4 (1.0 g) solid support was 13 added all at once to this solution, and the resulting i~ mixture was stirred for several minutes. All of the organochromium compound reacted with the solid support 16 yielding a deep purple catalyst and a clear supernatant.
17 The resulting catalyst slurry was filtered and the purple 18 solid was washed twice with 10 ml of THF and dried under i9 vacuum to a free flowing powder.

Z2 [Cp*CrCI~ (THF) 2] + [BPh4]' Z'8 This compound was prepared by the method described in Thomas Z5 et al., J. Amor. Che_fi. Soc , ~3, (1990), p. 900.
Z6 Preparation No. 13, method H was used to prepare compound 27 n~er 14 in that paper, i . e. , [Cp*CrCFl3 (THF) Z] + [HPh~]'.

SUPPORTED [Cp*CrCH3 (THF) 2] + [HPh4] -32 [Cp*Cr (THF) ] + [HPh ]- (0.075 33 ~ 2 4 9. 1.1 x 10''~ mole) was dissolved in 20 ml of THF and treated all at once with O1 1.00 g of A1203~2A1P04. The resulting mixture was stirred OZ for 15 minutes resulting in a dark blue solid and a clear 03 supernatant. The solid was washed with THF, and dried to a 04 free-flowing powder.
os os .
BTHYLBNB POLYMERIZATION USING AN UNSUPPORTBD CATALYST

O9 90 .1 micromolea of [Cp*CrCFi3 (THF) 2] + [HPh4] - was dissolved in 25 ml methylene chloride in a 50 ml Fiacher-Porter bottle, 11 and pressured to 50 psig with ethylene. The reactor was 1Z stirred at 25°C for 1.0 hour. Initially, the ethylene 13 uptake was rapid, but this rate decreased rapidly over the 1'~ first half hour. The reaction was stopped by venting the pressure. The polymer produced was washed with ieopropanol 16 and then with acetone. The polymer was then dried under 1~ vacuum. The results of this polymerization are indicated in 18 Run 1 in Tables I and II.

ZO

ZZ

Z~
zs zs s~

3~

21 0 88 fi 0 O1 c'OMPA_~?nTrVE EXAMPLE H
OZ ETHYLENE POLYMERIZATION USING

OS
05 The procedure of Comparative 8xample A was repeated, except 06 that 71 molar equivalents of isobutyl aluminoxane (IBAO) was 0~ added to the reaction vessel prior to pressurization with 08 ethylene. The results of this polymerization are indicated 09 in Run 2 in Tables I and II.
11 $~AMpLE 7 is ETHYLENE POLYI~RIZATION

1'~ Polymerization runs were conducted in 1 or 2 liter autoclave reactors under particle form (slurry) conditions using 16 between 300 and 500 ml heptane ae diluent, and a weighed 1~ amount of catalyst (typically 0.050 to 0.250 g). Run times 18 of 0.5 to 1.0 hour were normally employed. For example, in 19 a typical run, 0.100 g of the catalyst prepared in 8xample 4 (Cp*Cr (CH3) 2 (THF) adsorbed on A1203.2A1P04) was charged to a~
Z1 one-liter autoclave along with 300 ml of heptane.
ZZ Polyisobutylaluminoxane (0.5 ml of a 1. OM heptane solution, Z3 prepared by slow hydrolysis of triisobutylaluminum with 1.0 Z'~ equivalents of FIzO as in Bxample 3 of U.S. Patent No. 4,665,208, issued May 12, 1987 to Welborn et al., which Z6 patent is incorporated by reference herein) was added to the Z~ stirred reactor as co-catalyst. The reactor temperature and Z8 pressure were adjusted to 85° C. and 550 psi (with Z9 ethylene), respectively. The ethylene was supplied on d~nd from a pressurized reservoir. After 0.5 hour, the 31 reaction was stopped by rapidly cooling the reactor and 3Z venting the pressure. The polymer produced was washed with 33 isopropanol and acetone, and dried under vacuum to yield O1 82.9 g of white, granular solid. The results of this OZ polymerization are indicated in Run 15 in Tables III and IV.

Polymerization runs similar to that described above were 05 conducted using the catalysts and conditions shown in 06 Tables I, III, and V below. Analytical data for the polyethylenes produced in these rune is shown in Tables II, 08 IV and VI below. All molecular weights in these tables were O9 determined by gel permeation chromatography.
il The procedure of 8xample 7 is repeated in a 2 liter, stirred autoclave using the supported Cr+3 catalysts described 16 dove, except that heptane is not added to the autoclave.
1~ The reactor temperature and pressure are adjusted to 85~C
18 and 550 pai (with ethylene), respectively. A white, 19 granular polymer is produced.
ZO

ZZ

zs zs z~

3s C !~ N G M ~D G 10 !' N r' ~ ~i s N

a ~ ' a o o o o o ' ~ ~o e m . ~ o ' w If1 N

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M

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~-~ N e~f ~ Il'1 10 f~ O 0t O .~ eH n1 a Iff ~0 1~ O p~ O ,.~ N t~f O O O O O O O O O ~-1 ,.~ ,~ ,..t ,.~ ~ ,.~ ,.~ ",~ ~",~ N ~y H ty N

01 ~.~

OZ __ 03 ~YTIC11L POLYBTHYL~TBS PORTED
DAT11 PRSP71R~
FOR HITS
SUP

CP~Cr (T8F) R~ Supportp T~, Dlaeity ~ ~ifD
C

05 g/cc a 10';

Davieon 952 138.4 0.941 306 18.2 07 Silica 08 11 Davison 952 139.6 -- 293 19.2 Og Silica 10 12 Davison 955 138.3 -- 301 20.4 Silica iZ 13 Davieon 955 138.3 0.941 270 14.4 Silica 14 Al 0 2A.1P0 135 - - 805 2 .1 68 14 .

15 A1 0 2A1P0 134.7 -- 790 2.63 16 16 A1 0 2A1P0 136.6 0.927 1130 2.75 17 17 Al 0 2A1P0 139.0 0.924 917 4.13 18 18 Al 0 2A1P0 138.1 0.926 1134 5.61 pCalcined hours.
at for 9Detexmined by GPC.

ZZ

zs ss --w. 21 0 8 8 6 0 ~a ~, O O O
i~ N C O
s ~; ~ °' N
n o ~
H
V
~ O O O
N a N
O O c H
.~
A v v°
H
H ao a ~o a o y it c~ ~ cv b ~ U
N V V ~ o .~ rtf C". ~ ir' ~ N O \
W~ W~ ~ ~ U U
"i CI) ''~ fn O
a b ~ ~ v ~r~ r-~ rl p6 '~ N N
m .~ ~ a~
.~1 !V fr1 1~ If'1 1p !~ f~ 01 O .~1 N M 1~ ~f1 10 (~ O 41 O ~1 !V frf 1~
O O O O O O O O 0 ~~1 .~1 ,~ ,.~ ,.~ ~1 ,~~ ,~~ ..1 ~"~ !V lV N !N !V

TABLE
VI

ANALYTICAL
DATA
FOR
POLYETHYLENES
PREPARED

WITH
SUPPORTED
[Cp*CrMe2]2 Run Support T,~, Density Mean ParticleMw" MWD
C

g/cc Diameter, x 10-3 Microns 19 Davison 952 139.3 - - 910 252 23.5 Silica 20 Davison 955 140.6 - - - - 347 14.7 Silica PO9 . 3 °Calcined at 400°C for 48 hours.
"Determined by GPC.
Looking at Tables I and II, it can be seen that the polymerization using the homogeneous cationic Cr+3 compound has low activity (Run 1), and that adding triisobutvl-aluminoxane does not improve the activity, but rather reduces it (Run 2). These runs were performed at 25°C so as to avoid decomposition of the thermally labile homogeneous catalyst.
In contrast, Run 3 shows an approximately ten-fold improvement in activity using a supported catalyst system of this invention.
Runs 4-8 show the need for a co-catalyst when using this cationic Cr+3 compound. The aluminoxane co-catalyst gives improved activity over the trimethylaluminum co-catalyst.
Additionally, higher molecular weights (MW) and higher molecular weight distributions (MWD = MW/Mn) are obtained with the catalyst system of the present invention (see 2t oss so 01 Table II. The activity of this catalyst system was OZ highest when the support was an alumina aluminum phosphate 03 support, and the polymer had higher molecular weight as 0! well.
os 06 Looking at Tables III and IV, a co-catalyst appears to be necessary with the silica support and is advantageous with 08 the alumina aluminum phosphate support. Using the aluminoxane with the longer alkyl groups (isobutyl vs.
ethyl) gives higher activities. Also, the Davieon 955' 11 silica, which has a substantially smaller average particle is size than the Davison 952 silica, gives higher activity 13 (compare Runs 10 and 11 with Runa 12 and 13).
1!
Table III also shows that the catalyst systems of this 16 invention perform exceptionally well over the temperature 1~ range of 65°-85°C.

i9 Looking at Tables V and VI, the catalyst system of this ZO invention based on [Cp*Cr(CFLj)2]2 diner is also quite active, Z1 and gives polymers with very attractive high molecular ZZ weights and broad (high) MWD~s.

Z! BXAMPLB 9 zs Cp*Cr(TMSM)2 Z~ 1.318 g of CrCl3(THF)3 was placed in a 100 ml Schlenk flask Z8 along with a stirring bar and about 50-60 ml of THF.
29 0.500 g of Cp*Li was added to the resulting slurry producing 30 a blue solution ([Cp*CrC1272). This solution was allowed to 31 stir for at least three hours (preferably overnight). To 3Z the stirring solution was slowly added 2 equivalents of 33 LiCFLiBi (CFI3) 3. The solution changed from blue to purple.
3!

01 The THF was then removed by rotoevaporation and the OZ resulting solid was dissolved in pentane yielding a red 03 brown solution which was filtered to remove LiCl. The pentane was removed by rotoevaporation and the solid was 05 redissolved in a minimum amount of pentane and crystallized 06 at -30°C. Yield' S0-60~.

O8 It is important to note that this compound is thermally O9 unstable and decomposes at room temperature liberating tetramethylsilane.

is S1~1llL~LC~ 1 V
13 SUPPORTED Cp*Cr(TMSM)2 Cp*Cr(TMSM)2 (0.075 g) was dissolved in 10 ml of pentane.
16 p,~,203. 2p1P04 ( 1. 00 g) was added all at once to the stirred 17 solution resulting in the formation of a purple solid and i$ clear supernatant after 15 minutes. The solid was i9 collected, washed twice with pentane, and dried in vacuo to a free-flowing powder.

2 ~ $~LB'.l~

The ,upported Cp*Cr(TMSM)2 prepared in Bxample 10 was used Z5 to polymerize ethylene by a procedure similar to that described in 8~ca~mple 7, except that the polymerization was performed at 80°C-85°C and 550 psi total pressure (ethylene Z$ and hydrogen). The results of these polymerization rune are Z9 indicated in Table VII below, and analytical data for the polyethylenes produced are indicated in Table VIII below.

e. P O O O O O O O O N C1 rl N O W e~i!~ ~D !~ 10 tt1tl1 CO 01 i~ I'~1D O 10 d' e~ 10 d~ d~ tD O
N M d' N N ~''1er1 N N N N

i~

O
O O O O O O O O O O O O
~1 O O O O O O O O O O O O
Il1 O O O O O O O O O O
v-I

N O d' N O O d' O L'~~ 01 V' N M ~'~1N N N e~1 N N N v-1 V

V

i O ~ O O O O O O O O O O O O
r ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

E

H

H .. o a o 0 0 o o u~ ~n o 0 0 a ~ N N uw n o ..

H

o .-i ~ ,-i ~ .-~ .-i ,-i v N .

10 n'1 N 01 01 N N N N N N
~-i M ~ rl ~1 eh cn eh M M

H

p ~ O O O~ O O O O ~O O
a~~am ~ ~ ~ d cHao~~a a i N f~1er U1 ~O !'~CO 01 O v-1 N e1 N N N N N N N N cr1~1 e~1n1 N ~'~1 ! If! ~0 f'~ O 01 O ~1 N M ! 1f'1 10 t'~ O 01 O ~1 N N'1 1~
O O 0 O O O O O O ~ '~1 ,~1 .-1 ,~~ rl .~1 "a ,"~ ..1 t~1 !V N f~1 e,,~

b .~
a Gb y .: ~' o : i", v V

m o ~ N

.-~ Ci~
M ~ ~ O O b O O

W O
a' w ~ N .~., H o a o 0 s~
a N x o H w w ~

A ~ w ~ ~ N
U N v ~ y b H ~ ~ U U
H ~ M o Cr N
a ~ -~ ~ C~!

U ~ G
N ~ ~1 O
C~ ~r~ O L~
td .ri 'd ~ ~ b '' ,c ~ ~ ~ a ro b y v o a H
W ~

r.
i N m W ~ E m at '~ ~' ~ o ~t'~ ao a W N w N Nf ~ H
V'f ~ N ~f 1~ If1 ~0 1'~ O a O r~l N M 1~ t11 10 1~ O p~ O ,.I N M
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,..-..

T~18L8VIII
OZ -.

_ _ 03 ~~~=C1~L D11T11 FOR
POLYSTBYL~TSB

PitSP~ ORT~ (T1<
1IIT8 Cp*Cr ~M) SQPP

Os .

_ 05 R~1~ T=' C ~~ 8L1II

x 10~

23 139.1 0 0 1,124 2.02 08 24 139.4 0 0 891 7.61 09 25 136.3 - 1,075 2.72 26 138.1 - - 901 2.71 11 27 137.6 - - 824 2.42 lZ 28 139.9 0 0 _- --13 29 139.9 0 2.27 330 9.29 1~ 30 141.9 0 2.03 276 8.52 31 139.7 0 6.50 228 9.62 17 32 138.8 0 11.9 205.6 9.40 18 33 138.0 2.12 12.7 116.3 8.37 19 34 135.0 High High 55.8 10.50 ZO
'Melt Index (ASTM
D-1238, Condition 8) 21 melt index 8High (ASTM
load D-1238, Condition F) 9Determined by GPC.

~ 400C for runs ioSupport 48 dehydrated hours at for all .

3~

03 Cp*Cr(Hzyl)Z(THF) 0~
05 To a slurry of CrCl3(THF)3 (2.00 g, 5.33 mmoles) in 50 ml of 06 ~g was added LiCp* (0.76 g, 5.34 m~wles) slowly with stirring to yield a deep blue solution. This solution was 08 stirred for two hours. Slow addition of benzyl magnesium 09 chloride (5.3 ml of 2.0 M solution) resulted in a deep purple solution after complete addition. Solvent was 11 s~sequently removed under vacuum to yield a sticky purple iZ residue. Pentane (200 ml) was added and stirred overnight.
13 ~e pentane solution slowly became green-brown during this 1~ time. The pentane solution was filtered to remove metal halides, concentrated to ca. 75 ml and stored at -40°C
16 overnight. The crystalline material that formed was l~ collected, washed with cold pentane, and dried under vacuum, 18 affording 680 mg (29i~) of dark brown material.

COMPl~~?nTTVE BXAMpLB 13 Z1 HOMOG8N80US POLYMERIZATION WITH Cp*Cr(Hzyl)Z(THF) ZZ
Z3 Seventy-five milligrams of Cp*Cr(CH2Ph)2(THF) was dissolved in 50 ml of heptane and placed in a thick-walled glass Z5 vessel which was attached to a purified ethylene supply.
26 8thylene was added to 50 psi at ca. 20°C. A mild exotherm Z~ ensued with the generation of 0.70 g of beige polymer after Z8 one hour. The catalyst was essentially inactive after one Z9 hour as evidenced by the lack of ethylene uptake.

3~

Ol FXAMPLF 14 OZ
03 Cp*Cr(Hzyl)2(THF) was supported on A1203~2A1P04 (which had been dehydrated at 400°C for 48 hours) and used to 05 polymerize ethylene using the procedure described in 06 g~ple 11. The~results of these polymerization runs are 07 indicated in Tables IX and X below.

lZ

ZO

Z~

0 0 0 0 0 ., ''~ o a o o ~r Ll~ .. wn ~

y "' ~, 0 0 0 0 0 ar o 0 0 0 o m ..~ 0 0 0 0 0 o w a ui o ei w cN. o y d~el r, ,..ie~ o m d'N N t0 N ~"~ f.l \ O

~ '~ O
m a _ ~ O

~ O O O O O O ~ ~I
N

O

W

~

~I f'd 0 V

pl 0 0 0 0 o y InIn In In o ., w ~ In In r~
~

H ~ ~ b ' O

p p~ w b v ~' b N N N N N \ N , O

, h~ b ~

H i- m it ; ~ ~
b ~. , h ~ -rlId ~rN
~

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a rl N N N N N

riri e~ ri ri ~ ~ ~ ~

~ l~
rta b ~ U

a N ~ N

- ~r N rl ~ v O ~ w N

~ d' ~ i-I~ f-I

c~1ert O
d' O ~ ~

O rtf ~''rW N ~ ~ H

~1 N Iy1 ~ Ilf 1p t~ O 01 O ,.1 N M 1r Ill 1p N~ ID 01 O rl IV M
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Ol OZ

Z

3~T71LYTIC11L
D~1T11 FOR
pOL7CSTSYL~8 BRBP7I~t.SD
IIITB

05 Cp*Cr(Hsyl)=(TSg) Ruts T~, C Dl:iaity l~, :11''~ ~fD

Q$ 39 135.7 0.9288 1,243 1.75 Qg 40 135.4 0.9325 881 3.13 41 ___ ___ 22.6 2.34b lZ

sDetermined by GPC.

eData for homogeneous polymerization of unsupported catalyst Per Example 13.

17 $~MPLE

18 Cp t Cr ( ) ( Pyr ) ZO
This compound was prepared following the general description Zl contained in Noh, S.R.;
Sendlinger, 8.
C.;
Janiak, C.;

ZZ
Theopold, K.
H.
J.
Aan.
Chem Soc.
(1989), 111, 9127.
Lithium cyclopentadienide (0.380 g, 2.67 manol) was added slowly to a Z~
slurry of 1.

g (2 .

manol ) of CrCl3 (THF) in mL
of THF.

The resulting blue solution was stirred for hours.

Pyridine (0.222 g, 2.80 mmol) was added resulting in the deposition of a light blue solid.
Stirring was continued for hour after which was added (dropwise) 2.0 equivalents Zg (3.80 mL
of 1.4 M
solution in 8t20) of methyllithium.
The dark green-brown solutioa was stirred awadditional 0.5 hr and then taken to dryness under vacuum.
The dark solid was extracted into pentane, filtered to remove metal halides, and taken dryness.
The remaining solid was reextracted into pentane, filtered, and the solvent was reduced until 2~ os8 so O1 microcrystals appeared. The dark brown solution was kept at 0Z -40°C overnight resulting in the depositor of black 03 crystals. The crystals were collected and dried under 04 vacuum.
os 07 Cp*Cr(Hzyl)2(Pyr) 09 This compound was prepared as in Example 15 except that two equivalents of benzylmagnesium bromide were substituted for 11 methyllithium. A microcrystalline solid foxated and was i? dried under vacuum. Anal. Calc. for C~H34NCr: C,77.65;
13 H,7.64; N,3.12. Found: C,77.03; H,7.48; N,2.80.

$~pLB 17 16 Cp*Cr(TMSM)2(Pyr) 18 his compound was prepared as in Example 15 except that two i9 equivalents of trimethylsilylmethyllithium solution were ZO added in place of methyllithium. Long, black needles formed Z1 after cooling to -40 °C overnight. These were collected and ZZ dried to yield 1.30 g (55~) of pure material. Anal. Calc.
Z3 for C~H42N81ZCr: C, 62.67; H, 9.60; N, 3.17. Pound: C, Z4 62.36; H, 9.46; N, 2.84.

Z~ CP*Cr (CH3) 2 (DMAP) 29 This compound was prepared as described in Exaarple 15 except that 1.05 equivalents of N,N-dimethylaminopyridine (DMAP) 31 were added instead of pyridine. Large, dark brown crystals 32 were collected and dried under vacuum (710 mg, 78~ yield).

3~

01 Anal. Calc. (Found) for C19H3iN2Cr: C, 67.22 (66.69) ; H, 9.20 OZ (9.01) ; N, 8.25 (7.73) .

04 Lg 19 05 CpCr(CH3)2(DMAP) 06 .
This compound was prepared ae described in Example 15 except 08 that 1.0 equivalent of a 1.0 M solution of sodium O9 cyclopentadienide in the THF was added in place of lithium pentamethycyclopentadienide. Dark brows microcrystalslwere 11 obtained in 67~r overall yield (485 mg)~. Anal. Calc. (Found) iZ for C14H2iN2Cr: C, 62.43 (62.12) ; H, 7.88 (7.87) ; N, 10.40 13 (10.42).
l~
$~Lg 20 17 CP*Cr (CH3) 2 (PMe2Ph) 18 This co ound was mp prepared as described in Example 15 except i9 that 1.05 equivalents of dimethylphenylphoephine (PMe2Ph) were added instead of pyridine. Large blue/putple crystals Z1 were obtained in 56~ overall yield (530 mg). Anal. Calc.
22 (Found) for C~ZpCr: C, 67.58 (67.14); H, 9.07 (8.96); N, 23 0.0 (0.12) Z 6 F~~~l 2' CpCr ( CH3 ) 2 ( PMe2Ph ) This material was prepared according to Example 20 except that 1.0 equivalents of sodium cyclopentadienide was added in place of lithium pentamethylcyclpentadienide. Long blue/purple needles were obtained in 59~ yield (453 mg).

Anal. Calc. (Found) for CISH~PCr: c, 63.15 (62.33); H, 7.77 34 (7.59); N, 0.0 (0.0).

Ol EXAMPLE 22 OZ Cp*Cr(CH3)(3,5-Lutidine) Prepared as in 8xample 15 above except that 1.05 equivalents 05 of 3,5-lutidine were added in place of pyridine. Dark 06 microcrystals (510 mg, 59~) were collected and dried., Os EXAMPLB 23 09 CpCr(CH3)2(pyr) prepared as described in Example 15 above except that 1.0 11 equivalent of sodium cyclopentadienide was added instead of iZ lithium pentamethylcyclopentadienide.

1!
EXAMpLB 24 16 . SUPPORTED COMPLEXES

18 ~*Cr(CH3)2(Pyr), Cp*Cr(Hzyl)2(Pyr), Cp*Cr(TMSM)2(Pyr), 19 Cp*CrMe2(DMAP), CpCrMe2(DMAP), Cp*CrMe2EPMeZPh), CpCrMe (PMe Ph), Cp*CrMe (3,5-Lutidine), and 2 2 2 CpCrMe2 (Pyr) ~1 were individually supported on dehydrated (400 °C) supports 2~ as in Example 10 to give catalysts with ca 1.0 wt ~
Z3 chromium. The supports used are listed in the following Z4 tables.
z5 ss $~jrB 2 5 28 The su orted catal sts of PP y Example 24 were each in turn used to polymerize ethylene by a procedure similar to that described in Example 11. The results of these polymerization runs are indicated in the following tables.

3~

''~ 2~ os$ so Ol All molecular weight distributions were determined using 02 liquid size exclusion (gel permeation) chromatography. The 03 columns were Polymer Labs Inc. PLgel 20 dun Mixed-a columns.
04 The solvent used was 1,2,4-trichlorobenzene at a temperature 05 of 150°C.

All supports were dehydrated prior to use in order to 08 provide increased polymerization activity. Specific O9 dehydration temperatures and conditions are noted in the tables.
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Claims (45)

1. A catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, wherein the chromium compound is selected from Cp * Cr (CH3) 2 (DMAP) Cp * Cr (CH3) 2 (PMe2Ph) Cp * Cr (CH3) 2 (3,5-lutidine) CpCr (CH3) 3 (PMe2Ph) CpCr (CH3) 2 (DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl.

2. The catalyst system of Claim 1 wherein the support is an inorganic metal oxide or inorganic metal phosphate.

3. The catalyst system of Claim 1 wherein the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate.

4. The catalyst system of Claim 1 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

5. The catalyst system of Claim 4 wherein the support is alumina aluminum phosphate.

6. The catalyst system of Claim 3 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

7. The catalyst system of Claim 6 wherein the support is alumina aluminum phosphate.

8. A catalyst system for the homopolymerization and copolymerization of alpha-olefins having 2-8 carbon atoms, said catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, and a Group 2 or 3 metal alkyl compound, wherein the Group 6b metal compound is selected from Cp *(CH3)2(DMAP) Cp * Cr (CH3) 2 (PMe2Ph) Cp * Cr (CH3) 2 (3,5-lutidine) CpCr (CH3) 3 (PMe2Ph) CpCr (CH3) 2 (DMAP) wherein Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl and wherein the molar ratio of said metal alkyl compound to said chromium compound is about 1:1 to 1000:1.

9. The catalyst system of Claim 8 wherein the support is an inorganic metal oxide or inorganic metal phosphate.

10 . The catalyst system of Claim 9 wherein the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate.

11. The catalyst system of Claim 10 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

12. The catalyst system of Claim 11 wherein the support is alumina aluminum phosphate.

13. The catalyst system of Claim 8 wherein the Group 2 or Group 3 metal alkyl compound is an alkylaluminum compound.

14. The catalyst system of Claim 13 wherein the alkylaluminum compound is selected from the group consisting of trialkylaluminum compounds, alkylaluminum alkoxides, alkylaluminum halides and aluminoxanes.

15. The catalyst system of Claim 14 wherein the alkylaluminum compound is an aluminoxane or trialkylaluminum compound.

16. The catalyst system of Claim 8 wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate, and the Group 2 or 3 metal alkyl compound is an alkylaluminum compound.

17. The catalyst system of Claim 16 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

18. The catalyst system of Claim 17 wherein the support is alumina aluminum phosphate.

19. The catalyst system of Claim 16 wherein the alkylaluminum compound is selected from the group consisting of trialkylaluminum compounds, alkylaluminum alkoxides, alkylaluminum halides and aluminoxanes.

20. The catalyst system of Claim 19 wherein the alkylaluminum compound is an aluminoxane or trialkylaluminum compound.

21. The catalyst system of Claim 8 wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) the support is silica or alumina aluminum phosphate, and the alkylaluminum compound is an aluminoxane or a trialkylaluminum compound,

22. The catalyst system of Claim 21 wherein the support is alumina aluminum phosphate.

23. A process for the homopolymerization or copolymerization of alpha-olefins having 2-8 carbon atoms comprising polymerizing said alpha-olefin, or copolymerizing two or more alpha-olefins in the presence of a catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N-dimethylaminopyridine, PMe2Ph is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl.

24. The process of Claim 23 wherein the support is an inorganic metal oxide or inorganic metal phosphate.

25. The process of Claim 23 wherein the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate.

26. The process of Claim 25 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

27. The process of Claim 26 wherein the support is alumina aluminum phosphate.

28. The process of Claim 23 wherein the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate.

29. The process of Claim 28 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

30 . The process of Claim 29 wherein the support is alumina aluminum phosphate.

31. A process for the homopolymerization or copolymerization of alpha-olefins comprising polymerizing said alpha-olefin, or copolymerizing two or more alpha-olefins in the presence of a catalyst system comprising a cyclopentadienyl Group 6b metal chromium compound in which the metal has an oxidation state of +3, said Group 6b metal compound being supported on an inorganic support, and a Group 2 or 3 metal alkyl compound, wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) where Cp* is pentamethylcyclopentadienyl, DMAP is N,N--dimethylaminopyridine, PMejPh is dimethylphenylphosphine, and Cp is unsubstituted cyclopentadienyl and wherein the molar ratio of said metal alkyl compound to said chromium compound is about 1:1 to 1000:1.

32. The process of Claim 31 wherein the support is an inorganic metal oxide or inorganic metal phosphate.

33. The process of Claim 32 wherein the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate.

34. The process of Claim 33 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

35, The process of Claim 34 wherein the support is alumina aluminum phosphate.

36. The process of Claim 31 wherein the Group 2 or Group 3 metal alkyl compound is an alkylaluminum compound.

37. The process of Claim 36 wherein the alkylaluminum compound is selected from the group consisting of trialkylaluminum compounds, alkylaluminum alkoxides, alkylaluminum halides and aluminoxanes.

38. The process of Claim 37 wherein the alkylaluminum compound is an aluminoxane or trialkylaluminum compound.

39. The process of Claim 31 wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) the support is selected from the group consisting of alumina, silica, silica-alumina, aluminum phosphate, zirconium phosphate, and alumina aluminum phosphate, and the Group 2 or 3 metal alkyl compound is an alkylaluminum compound.

40. The process of Claim 39 wherein the support is selected from silica, aluminum phosphate and alumina aluminum phosphate.

41. The process of Claim 40 wherein the support is alumina aluminum phosphate.

42. The process of Claim 39 wherein the alkylaluminum compound is selected from the group consisting of trialkylaluminum compounds, alkylaluminum alkoxides, alkylaluminum halides and aluminoxanes.

43. The process of Claim 42 wherein the alkylaluminum compound is an aluminoxane or trialkylaluminum compound.

44. The process of Claim 39 wherein the Group 6b metal compound is selected from CP * Cr(CH3)2(DMAP) Cp * Cr(CH3)2(PMe2Ph) Cp * Cr(CH3)2(3,5-lutidine) CpCr(CH3)3(PMe2Ph) CpCr(CH3)2(DMAP) the support is silica or alumina aluminum phosphate, and the alkylaluminum compound is an aluminoxane or a trialkylaluminum compound.

45. The process of Claim 44 wherein the support is alumina aluminum phosphate.