Preparation of ultra high molecular weight ethylene copolymer

Patent metadata

Field	Value
Publication number	US-2016229932-A1
Application number	US-201415029894-A
Country	US
Kind code	A1
Filing date	Oct 24, 2014
Priority date	Oct 25, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

The invention relates to a process for the preparation of a particulate ultra high molecular weight polyethylene (pUHMWPE copolymer, comprising the steps of preparing a magnesium containing carrier, loading the carrier with a organometallic compound forming a supported catalyst and contacting the supported catalyst with ethylene and at least one olefinic co-monomer under polymerization conditions, wherein the organometallic compound is of the formula R 3 3 P═N—TiCpX n .

First claim

1 . Process for preparation of a particulate ultra high molecular weight polyethylene (pUHMWPE), comprising the steps of
a) preparing a magnesium containing carrier by interaction of a solution of an organomagnesium compound having composition MgR 1 2 .nMgCl 2 .mR 2 2 O where n=0.37-0.7, m=1.1-3.5, R 1 is each an aromatic or aliphatic hydrocarbyl residue and R 2 2 O is an aliphatic ether, with a chlorinating agent at a molar ratio Mg/Cl of at most 0.5, wherein Mg represents the Mg of the organomagnesium compound and Cl the Cl of the chlorinating agent; b) loading the magnesium containing carrier with a organometallic compound forming a supported catalyst, c) contacting the supported catalyst with ethylene and at least one olefinic co-monomer under polymerization conditions, wherein the organometallic compound is a compound of the formula R 3 3 P=N—TiCpX n , wherein each R 3 is independently selected from the group consisting of
a hydrogen atom,
a halogen atom,
a C 1-20 hydrocarbyl radicals optionally substituted by at least one halogen atom,
a C 1-8 alkoxy radical,
a C 6-10 aryl or aryloxy radical,
an amido radical,
a silyl radical of the formula —Si—(R 4 ) 3
and a germanyl radical of the formula —Ge—(R 4 ) 3
wherein each R 4 is independently selected from the group consisting of hydrogen, a C 1-8 alkyl or alkoxy radical, C 6-10 aryl or aryloxy radicals, Cp is a cyclopentadienyl ligand; X is an activatable ligand and n is 1 or 2, depending upon the valence of Ti and the valence of X, preferably, X is selected from the group consisting of Cl, Br, Me and Et if n=2 or X is a substituted or unsubstituted butadiene if n=1.

2 . The process of claim 1 wherein the co-monomer is selected from the group consisting of an alpha-olefin with at least 3 carbon atoms, a cyclic olefin having 5 to 20 carbon atoms and a linear, branched or cyclic diene having 4 to 20 carbon atoms.

3 . The process of claim 1 comprising the step of treating the magnesium containing carrier or the organometallic compound with an activator selected from the list of alumoxanes, alkyl aluminiums, alkyl aluminum halides, anionic compounds of boron or aluminum, trialkylboron compounds, triarylboron compounds, borates, and mixtures thereof, preferably the activator is alumoxanes or alkyl aluminums.

4 . The process according to claim 1 wherein the magnesium containing carrier has a D50 of 2 to 30 μm.

5 . The process of claim 1 wherein the chlorinating agent is a chlorine-containing compound of composition Y k ACl 4-k , where Y═OR 5 or R 5 group with R 5 being a C 1-20 hydrocarbyl radicals optionally substituted by at least one halogen atom, A being Si or C atom and k=0 to 2.

6 . The process of claim 1 wherein the organometallic compound is of the formula t Bu 3 P═N—TiCp*X 2 , wherein Cp* is pentamethylcyclopentadienyl and X is selected from the group consisting of Cl, Br, Me and Et.

7 . The ultrahigh molecular weight polyethylene obtainable by any of the processes according to claim 1 .

8 . Particulate ultra high molecular weight polyethylene (pUHMWPE) having
an intrinsic viscosity (IV) of at least 4 dl/g, a co-monomer content of a least 0.05 SCB/1000TC, a co-monomer partition factor (C pf ) of at least 0.8, a median particle size D50 of between 50 and 500 μm, a total ash content of less than 1000 ppm.

9 . pUHMWPE according to claim 8 , wherein the polymer has a molecular weight distribution, M w /M n , of less than 4.0.

10 . pUHMWPE according to claim 8 , wherein the co-monomer selected from the group consisting of an alpha-olefin with at least 3 carbon atoms, a cyclic olefin having 5 to 20 carbon atoms and a linear, branched or cyclic diene having 4 to 20 carbon atoms.

11 . pUHMWPE according to claim 8 wherein the UHMWPE has a residual Si-content of less than 100 ppm.

12 . pUHMWPE according to claim 8 wherein the UHMWPE has an apparent bulk density of at least 300 kg/m 3 .

13 . Process for manufacturing of a molded UHMWPE articles comprising the pUHMWPE of claim 8 .

14 . The process according to claim 13 wherein the molded article is a fiber, tape or film.

15 . A product comprising the molded articles according to claim 13 , preferably the article is selected from the group consisting of ropes, cables, nets, fabrics, and protective appliances such as ballistic resistant articles.

Assignees

• Dsm Ip Assets Bv

Inventors

• Severn John Richard
• Berthoud Romain
• Kidd Timothy James

Classifications

• C08F210/16

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• C08F4/65912

  in combination with an organoaluminium compound · CPC title

• C08F2500/18

  Bulk density · CPC title

• C08F110/02 Primary

  Ethene · CPC title

• C08F4/65916

  supported on a carrier, e.g. silica, MgCl2, polymer · CPC title