Scalable production of precision hydrocarbons from trialkylaluminum via ternary living coordinative chain transfer polymerization
Disclosed is a method of producing a polyolefin composition comprising contacting a metallocene pre-catalyst, a co-catalyst, a primary surrogate, and a secondary surrogate; adding a first olefin monomer; and polymerizing the first monomer for a time sufficient to form the polyolefin. Also disclosed is a method of producing a block polyolefin composition comprising contacting a metallocene pre-catalyst, a co-catalyst, a primary surrogate, and a secondary surrogate; 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. The method allows for the production of polyolefins of low molecular weights and narrow molecular weight distributions.
1. A method of producing a polyolefin composition comprising:
(a) contacting a metallocene pre-catalyst, a co-catalyst, of Al(R 8 ) 3 , wherein R 8 is a C 1 -C 10 alkyl, and Zn(R 9 ) 2 , wherein R 9 is a C 1 -C 10 alkyl;
(b) adding a first olefin monomer; and
(c) polymerizing by ternary living coordinative chain transfer said first olefin monomer for a time sufficient to form said polyolefin, wherein Al(R 8 ) 3 and Zn(R 9 ) 2 are added in a ratio of about 1.1:1 to about 100:1.
2. The method of claim 1 , wherein R 8 is selected from the group consisting of ethyl, methyl, iso-butyl, n-hexyl, n-propyl, and t-butyl.
3. The method of claim 2 , wherein R 8 is iso-butyl.
4. The method of claim 2 , wherein R 8 is ethyl.
5. The method of claim 2 , wherein R 8 is n-propyl.
6. The method of claim 1 , wherein R 9 is selected from the group consisting of methyl, ethyl, n-butyl, isoamyl, t-butyl, neopentyl, n-propyl, and iso-propyl.
7. The method of claim 6 , wherein R 9 is ethyl.
8. The method of claim 1 , wherein said ratio is about 9:1.
9. The method of claim 1 , wherein said ratio is about 19:1.
10. 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)].
11. The method of claim 1 , wherein said co-catalyst is selected from the group consisting of [PhNMe 2 H][B(C 6 F 5 ) 4 ], [PhNMe 2 H][B(C 6 F 5 ) 3 Me], and B(C 6 F 5 ) 3 .
12. The method of claim 1 , wherein the Al(R 8 ) 3 and Zn(R 9 ) 2 are contacted with the metallocene pre-catalyst and the co-catalyst in an inert solvent.
13. The method of claim 12 , wherein said solvent is toluene.
14. The method of claim 1 , wherein the Al(R 8 ) 3 , the Zn(R 9 ) 2 , the metallocene pre-catalyst, and the co-catalyst are contacted at a temperature of about −20° C. to about 25° C.
15. The method of claim 1 , wherein the first olefin monomer is selected from the group consisting of ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, butadiene, isoprene, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexane, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure β-citronellene, 3,5,5-trimethyl-1-hexene, cyclopentene, vinylcyclohexene, and 4-methyl-1-pentene.
16. The method of claim 1 , wherein the first olefin monomer is selected from the group consisting of ethene, propene, 1-hexene, 1-octene, and 1,5-hexadiene.
17. The method of claim 1 , wherein the polyolefin is an atactic polyolefin having a polydispersity index of about 1.01-1.15.
18. The method of claim 1 , wherein the metallocene pre-catalyst is (η 5 -C 5 Me 5 )Hf(Me) 2 [N(Et)C(Me)N(Et)], R 8 is ethyl, R 9 is ethyl, and the first olefin monomer is propene.
19. The method of claim 1 , wherein the metallocene pre-catalyst is (η 5 -C 5 Me 5 )Hf(Me) 2 [N(Et)C(Me)N(Et)], R 8 is n-propyl, R 9 is ethyl, and the first olefin monomer is propene.
20. The method of claim 1 , wherein the metallocene pre-catalyst is (η 5 -C 5 Me 5 )Hf(Me) 2 [N(Et)C(Me)N(Et)], R 8 is iso-butyl, R 9 is ethyl, the first olefin monomer is propene.
21. The method of claim 20 , wherein the ratio of Al(R 8 ) 3 to Zn(R 9 ) 2 is from about 9:1 to about 19:1.
22. The method of claim 1 , further comprising adding a second olefin monomer; and polymerizing said second monomer for a time sufficient to form a polyolefin block copolymer.
23. The method of claim 22 , wherein said second olefin monomer is selected from the group consisting of ethene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, styrene, butadiene, isoprene, 3-methylbutene, 3-methyl-1-pentene, vinylcyclohexane, vinylcyclobutane, vinylcyclopentane, vinylcyclooctane, 1-decene, enantiomerically pure β-citronellene, 3,5,5-trimethyl-1-hexene, and 4-methyl-1-pentene.
24. The method of claim 22 , wherein said polyolefin block copolymer is an atactic living polyolefin.
25. The method of claim 22 , wherein said polyolefin block copolymer comprises a diblock copolymer having the formula: atactic-poly(first olefin)-co-poly(second olefin).
26. The method of claim 22 , wherein said polyolefin block copolymer has a polydispersity index of about 1.02-1.2.
27. The method of claim 22 , wherein said polyolefin block copolymer is monomodal.
28. The method of claim 22 , wherein the metallocene pre-catalyst is (η 5 -C 5 Me 5 )Hf(Me) 2 [N(Et)C(Me)N(Et)], R 8 is iso-butyl, R 9 is ethyl, the first olefin monomer is propene, and the second olefin monomer is 1-octene.
29. The method of claim 28 , wherein the ratio of Al(R 8 ) 3 to Zn(R 9 ) 2 is about 9:1.