Process for preparation of polyolefins via living coordinative chain transfer polymerization
Disclosed is a method of producing a polyolefin composition comprising contacting a metallocene pre-catalyst, co-catalyst, and a stoichiometric excess of a metal alkyl; adding a first olefin monomer; and polymerizing the first monomer for a time sufficient to form the polyolefin. The method allows for the use of minimum amounts of activating co-catalyst and metallocene pre-catalyst. Also disclosed is a method of producing a block polyolefin composition comprising contacting a metallocene pre-catalyst, a co-catalyst, and a stoichiometric excess of a metal alkyl; adding a first olefin monomer; polymerizing the first monomer for a time sufficient to form the polyolefin; adding a second monomer; and polymerizing the second olefin monomer for a time sufficient to form said block polyolefin composition. Also disclosed are amorphous atactic polymer and copolymer compositions made according to the present invention.
1. A method of producing a polyolefin composition comprising contacting a metallocene pre-catalyst, a co-catalyst, and a stoichiometric excess of a metal alkyl; adding a first olefin monomer; and polymerizing by living coordinative chain transfer said first monomer for a time sufficient to form said polyolefin.
2. The method of claim 1 , wherein said metallocene pre-catalyst is η 5 -C 5 Me 5 *Hf(Me) 2 [N(Et)C(Me)N(Et)].
3. The method of claim 1 , wherein said co-catalyst is [PhNMe 2 H][B(C 6 F 5 ) 4 ], [PhNMe 2 H][B(C 6 F 5 ) 3 Me] or B(C 6 F 5 ) 3 .
4. The method of claim 1 , wherein said metal alkyl consists of a mixture of two different metal alkyls.
5. The method of claim 4 , wherein said mixture of metal alkyls consists of a 1:1 mixture of AlEt 3 and ZnEt 2 .
6. The method of claim 1 , wherein said metal alkyl is ZnEt 2 or Zn(iso-propyl) 2 .
7. The method of claim 1 , wherein said metallocene pre-catalyst and said co-catalyst are contacted in a metallocene pre-catalyst:co-catalyst ratio of about 1:1.
8. The method of claim 1 , wherein said metal alkyl and metallocene pre-catalyst are added in a metal alkyl:metallocene pre-catalyst ratio of about 5000:1-1.1:1.
9. The method of claim 8 , wherein said ratio is 5:1 to 200:1.
10. The method of claim 8 , wherein said ratio is 50:1.
11. The method of claim 8 , wherein said ratio is 20:1.
12. The method of claim 8 , wherein said ratio is 10:1.
13. The method of claim 1 , wherein said metal alkyl is contacted with said metallocene pre-catalyst and said co-catalyst in an inert solvent.
14. The method of claim 13 , wherein said solvent is toluene.
15. The method of claim 1 , wherein said metal alkyl, said metallocene pre-catalyst, and said co-catalyst are contacted at a temperature of about −20° C. to about 25° C.
16. The method of claim 1 , wherein said first olefin monomer is ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, alpha-methyl styrene, butadiene, isoprene, acrylonitrile, methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, vinyl fluoride, vinylidene chloride, N-vinyl pyrrolidone, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexane, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure β-citronellene, 3,5,5-trimethyl-1-hexene, cyclopentene, vinylcyclohexene or 4-methyl-1-pentene.
17. The method of claim 1 , wherein said first olefin monomer is a non-conjugated diene having the formula:
wherein X═CH 2 , CO, N(R 13 ), O or S;
R 11 , R 12 and R 13 are each indepedently H, alkyl or phenyl; and
n and m are each independently an integer from 0-5.
18. The method of claim 1 , wherein said first olefin monomer is ethene, propene, 1-hexene, 1-octene, or 1,5-hexadiene.
19. The method of claim 1 , wherein said polyolefin is an atactic polyolefin having a polydispersity index of about 1.03-1.15.
20. The method of claim 1 , further comprising adding a second olefin monomer; and polymerizing said second monomer for a time sufficient to form said polyolefin.
21. The method of claim 20 , wherein said second olefin monomer is ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, alpha-methyl styrene, butadiene, isoprene, acrylonitrile, methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, vinyl fluoride, vinylidene chloride, N-vinyl pyrrolidone, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexane, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure β-citronellene, 3,5,5-trimethyl-1-hexene or 4-methyl-1-pentene.
22. The method of claim 20 , wherein said second olefin monomer is a non-conjugated diene having the formula:
wherein X═CH 2 , CO, N(R 13 ), O or S;
R 11 , R 12 and R 13 are each independently H, alkyl or phenyl; and
n and m are each independently an integer from 0-5.
23. The method of claim 20 , wherein said polyolefin is an atactic living polyolefin.
24. The method of claim 20 , wherein said block-polyolefin composition comprises a diblock copolymer having the formula: atactic-poly(first olefin)-co-poly(second olefin).
25. The method of claim 20 , wherein said diblock copolymer composition has a polydispersity index of about 1.02-1.2.
26. The method of claim 20 , wherein said diblock copolymer is monomodal.
27. A method of producing a polyolefin composition comprising contacting η 5 -C 5 Me 5 *Hf(Me) 2 [N(Et)C(Me)N(Et)], [PhNMe 2 H][B(C 6 F 5 ) 4 ], and a stoichiometric excess of ZnEt 2 ; adding a first olefin monomer; and polymerizing said first monomer by living coordinative chain transfer for a time sufficient to form said polyolefin.
28. The method of claim 27 , wherein the first olefin monomer is propene.
29. The method of claim 27 , wherein the first olefin monomer is ethene.
30. The method of claim 27 , wherein said η 5 -C 5 Me 5 *Hf(Me) 2 [N(Et)C(Me)N(Et)] and said ZnEt 2 are contacted in a ratio of 5:1 to 200:1.
31. A method of producing a polyolefin composition comprising contacting η 5 -C 5 Me 5 *Hf(Me) 2 [N(Et)C(Me)N(Et)], [PhNMe 2 H][B(C 6 F 5 ) 4 ], and a stoichiometric excess of ZnEt 2 ; adding a first olefin monomer; adding a second olefin monomer; and polymerizing said monomers by living coordinative chain transfer for a time sufficient to form said polyolefin.
32. The method of claim 31 , wherein the first olefin monomer is ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, alpha-methyl styrene, butadiene, isoprene, acrylonitrile, methyl acrylate, methyl methacrylate, vinyl acetate, vinyl chloride, vinyl fluoride, vinylidene chloride, N-vinyl pyrrolidone, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexene, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure (3-citronellene, 3,5,5-trimethyl-1-hexene, cyclopentene, vinylcyclohexene, 4-methyl-1-pentene or a non-conjugated diene having the formula:
wherein X═CH 2 , CO, N(R 13 ), O or S;
R 11 , R 12 and R 13 are each indepedently H, alkyl or phenyl; and
n and m are each independently an integer from 0-5;
and the second olefin monomer is 1-hexene, 1-octene or 1,5-hexadiene.
33. The method of claim 31 , wherein the first olefin monomer is ethene and the second olefin monomer is 1-hexene, 1-octene or 1,5-hexadiene.