Catalyst composition comprising shuttling agent for ethylene copolymer formation

1. A composition comprising the admixture or reaction product resulting from combining:

(A) a first olefin polymerization catalyst,

(B) a second olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions,

at least one of catalyst (A) or catalyst (B) being capable of forming a branched polymer by means of chain walking or reincorporation of in situ formed olefinic polymer chains, and

(C) a chain shuttling agent

wherein catalyst (A) corresponds to the formula:

wherein:

R 11 is selected from alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl, aryl, and inertly substituted derivatives thereof containing from 1 to 30 atoms not counting hydrogen or a divalent derivative thereof;

T 1 is a divalent bridging group of from 1 to 41 atoms other than hydrogen; and

R 12 is a C 5-20 heteroaryl group containing Lewis base functionality;

M 1 is a Group 4 metal;

X 1 is an anionic, neutral or dianionic ligand group;

x′ is a number from 0 to 5 indicating the number of such X 1 groups; and

bonds, optional bonds and electron donative interactions are represented by lines, dotted lines and arrows respectively.

2. A composition according to claim 1 wherein the shuttling agent is a trihydrocarbyl aluminum- or dihydrocarbyl zinc- compound containing from 1 to 12 carbons in each hydrocarbyl group.

3. A composition according to claim 2 wherein the shuttling agent is triethylaluminum or diethylzinc.

4. A composition according to claim 1 wherein catalyst (B) corresponds to the formula:

wherein

M 2 is a metal of Groups 4-10 of the Periodic Table of the elements;

T 2 is a nitrogen, oxygen or phosphorus containing group;

X 2 is halo, hydrocarbyl, or hydrocarbyloxy;

t is one or two;

x″ is a number selected to provide charge balance;

and T 2 and N are linked by a bridging ligand.