Polyolefin production

1. A process for preparing a polyethylene copolymer, which comprises:

supplying ethylene monomer;

supplying hexene monomer;

forming butene in situ and copolymerizing ethylene monomer, hexene monomer and the butene monomer formed in situ in the presence of a catalyst system comprising:

a metallocene compound of general formula

Ind 2 R″MQ 2

having a mole ratio of meso to racemic forms of the metallocene of at least 1:3,

wherein each Ind is the same or different, and is indenyl or substituted indenyl,

wherein R″ is an ethylene bridge that is substituted or unsubstituted, and

wherein the cyclopentadienyl ring of at least one of the indenyls is unsubstituted without regard to the bridge R″,

wherein M is a Group IV metal or vanadium, and

wherein each Q is a hydrocarbyl having 1 to 20 carbon atoms or a halogen, and

a cocatalyst

wherein the process is a solution polymerization process or a slurry process; and

recovering said polyethylene.

2. The process according to claim 1 , wherein the polyethylene copolymer formed thereby has a shear ratio of at least 20.

3. The process according to claim 1 , wherein the cocatalyst comprises triisobutylaluminium (TBAC).

4. The process according to claim 1 , wherein hydrogen is added during polymerization.

5. The process according to claim 1 , wherein butene is formed in situ by dimerization of the ethylene.

6. The process according to claim 5 , wherein a polymerization activity increases with increasing hexene comonomer content.

7. The process according to claim 1 , wherein the polyethylene formed thereby has branching arising from butene incorporation into the backbone of the polyethylene.

8. A process according to claim 1 , wherein the cocatalyst comprises an aluminum-containing cocatalyst or a boron-containing cocatalyst.

9. A process according to claim 8 , wherein the cocatalyst comprises an aluminum-containing cocatalyst comprised of an alumoxane, an alkyl aluminum and/or a Lewis acid.

10. A catalyst according to claim 9 , wherein the cocatalyst is a oligomeric linear and/or a cyclic alkyl alumoxanes represented by:

for oligomeric, linear alumoxane and

for oligomeric, cyclic alumoxane; and

wherein n is 1-40, m is 3-40, and R is a C 1 -C 8 alkyl group.

11. The process according to claim 1 , wherein the polyethylene copolymer formed thereby has long chain branching.

12. The process according to claim 1 , wherein the ethylene is polymerized in a solution that further is comprised of a solvent, and wherein the solvent is heptane, toluene, or cyclohexane.

13. A process for polymerizing ethylene comprising:

forming a supported metallocene catalyst by

adding an alumoxane;

adding a metallocene compound of the general formula

Ind 2 R″MQ 2

having a mole ratio of meso to racemic forms of the metallocene of at least 1:3,

wherein each Ind is the same or different and is an indenyl or a substituted indenyl,

wherein R″ is an ethylene bridge that is substituted or unsubstituted, and

wherein a cyclopentadienyl ring of at least one of the indenyls in unsubstituted without regard to the bridge R″,

wherein M is a Group IV metal or vanadium, and

wherein each Q is hydrocarbyl having 1 to 20 carbon atoms or halogen; and

adding a cocatalyst;

contacting said supported catalyst with an ethylene monomer and a hexene monomer;

forming butene in situ;

forming an ethylene/butene/hexene copolymer

wherein the process is a solution polymerization process or a slurry process; and

recovering said ethylene/butene/hexene copolymer.

14. The process according to claim 13 , wherein hydrogen is added to said reaction medium.

15. The process according to claim 13 , wherein butene is formed in situ by dimerization of ethylene.

16. The process according to claim 15 , wherein a polymerization activity increases with increasing hexene comonomer content.

17. The process according to claim 13 , wherein the ethylene/butene/hexene copolymer formed thereby has a shear ratio of at least 20.