Process for making high molecular weight Isobutylene polymers

1 . A process for polymerizing a cationically polymerizable olefin comprising the step of:

polymerizing at least one cationically polymerizable olefin at a subatmospheric pressure, in the presence of,

a cationic polymerization catalyst system,

wherein the catalyst system which comprises

an initiator and an activator,

wherein the initiator and the activator together form a reactive cation and non-co-ordinating anion, and

wherein the activator is prepared by the reaction of a compound of formula (R 1 R 2 R 3 )M with a co-initiator,

wherein

M is B, Al, Ga or In;

R 1 , R 2 and R 3 are independently selected from the group consisting of bridged or unbridged halide radicals, dialkylamido radicals, alkoxide and aryloxide radicals, hydrocarbyl and substituted-hydrocarbyl radicals, halocarbyl and substituted-halocarbyl radicals and hydrocarbyl and halocarbyl-substituted organometalloid radicals, wherein not more than one R group is a halide radical, and

wherein, the co-initiator is selected from the group consisting of an alcohol, a thiol, a carboxylic acid, a thiocarboxylic acid and mixtures thereof.

2 . A process according to claim 1 , wherein M is B.

3 . A process according to claim 1 , wherein the ratio of co-initiator to (R 1 R 2 R 3 )M is in the range of from 0.01:1 to 1:1.

4 . A process according to claim 3 , wherein the ratio of co-initiator to (R 1 R 2 R 3 )M is in the range of from about 0.1:1 to about 1:1.

5 . A process according to claim 1 , wherein the reactive cation is a cyclopentadienyl transition metal complex.

6 . A process according to claim 5 , wherein the transition metal complex is a compound selected from the group consisting of:

wherein

(A-Cp) is either (Cp)(Cp*) or Cp-A′-Cp*; and

wherein

Cp and Cp* are the same or different cyclopentadienyl rings substituted with from 0 to 5 substituent groups S, each substituent group S being, independently, a radical group selected from the group consisting of hydrocarbyl, substituted-hydrocarbyl, halocarbyl, substituted-halocarbyl, hydrocarbyl-substituted organometalloid, halocarbyl-substituted organometalloid, disubstituted boron, disubstituted pnictogen, substituted chalcogen or halogen radicals, or

Cp and Cp* are cyclopentadienyl rings in which any two adjacent S groups are joined forming a C 4 to C 20 ring system to give a saturated or unsaturated polycyclic cyclopentadienyl ligand;

R is a substituent on one of the cyclopentadienyl radicals which is also bonded to the metal atom;

A′ is a bridging group, which group may serve to restrict rotation of the Cp and Cp* rings or (C 5 H 5-y-x S x ) and JR′( z-1-y ) groups;

M is a Group 4, 5, or 6 transition metal;

y is 0 or 1;

(C 5 H 5-y-x S x ) is a cyclopentadienyl ring substituted with from 0 to 5 S radicals;

x is from 0 to 5;

JR′( z-1-y ) is a heteroatom ligand in which J is a Group 15 element with a co-ordination number of three or a Group 16 element with a co-ordination number of 2;

R″ is a hydrocarbyl group;

X and X 1 are independently selected from the group consisting of a hydride radical, hydrocarbyl radical, substituted hydrocarbyl radical, halocarbyl radical, substituted halocarbyl radical, and hydrocarbyl- and halocarbyl-substituted organometalloid radical, substituted pnictogen radical, or substituted chalcogen radicals; and

L is selected from the group consisting of an olefin, diolefin, aryne ligand and a neutral Lewis base.

7 . A process according to claim 1 , wherein R 1 , R 2 and R 3 are independently selected from the group consisting of aromatic or substituted aromatic hydrocarbon radicals having in the range of from 6 to 20 carbon atoms.

8 . A process according to claim 7 , wherein R 1 , R 2 and R 3 are linked to each other by a table bridging group.

9 . A process according to claim 2 , wherein R 1 , R 2 and R 3 are each a C 6 F 5 group.

10 . A process according to claim 1 , wherein the co-initiator is fluorinated.

11 . A process according to claim 1 , wherein the polymerization is carried out at a temperature higher than −100° C.

12 . A process according to claim 1 , wherein the subatmospheric pressure is less than about 100 kPa.

13 . A process according to claim 1 , wherein the at least one cationically polymerizable olefin comprises a mixture of isobutylene and isoprene.

14 . A process for polymerizing a cationically polymerizable olefin comprising the step of:

polymerizing at least one cationically polymerizable olefin in the presence of a cationic polymerization catalyst system,

wherein the catalyst system comprises an initiator and an activator,

wherein the activator is prepared by the reaction of a compound of formula (R 1 R 2 R 3 )M and a co-initiator

wherein,

M is B, Al, Ga or In;

R 1 , R 2 and R 3 are independently selected from the group consisting of bridged or unbridged halide radicals, dialkylamido radicals, alkoxide and a7969ryloxide radicals, hydrocarbyl and substituted-hydrocarbyl radicals, halocarbyl and substituted-halocarbyl radicals and hydrocarbyl and halocarbyl-substituted organometalloid radicals,

wherein not more than one such R group may be a halide radical; and

wherein the co-initiator is selected from the group consisting of an alcohol, a thiol, a carboxylic acid, a thiocarboxylic acid and mixtures thereof, and wherein the reaction is carried out such that highly efficient cooling of the reaction mixture occurs.