Claims
- 1. A gel-free process for making hydrogenated functionalized anionic polymers using a multi-alkali metal initiator which comprises:(a) anionically polymerizing at least one monomer with a multi-alkali metal initiator in a hydrocarbon solvent, (b) capping the polymer by adding to the polymer a capping agent that reacts with the ends of the polymer chains such that strongly associating chain ends are formed wherein a polymer gel is formed, (c) adding a trialkyl aluminum compound to the polymer gel whereby the gel dissipates, (d) optionally terminating the polymerization by addition of a terminating agent, (e) washing the polymer with aqueous acid, and (f) hydrogenating the polymer with a hydrogenation catalyst.
- 2. The process of claim 1 wherein the initiator is a dilithium initiator.
- 3. The process of claim 1 wherein the acid is a mineral acid.
- 4. The process of claim 3 wherein the mineral acid is phosphoric acid wherein there is at least one mole of phosphoric acid per mole of alkali metal and at least three moles of phosphoric acid per mole of aluminum.
- 5. The process of claim 4 wherein the concentration of the acid in step (e) is from 20 to 40 percent by weight and the phase weight ratio of aqueous acid to polymer plus solvent is from 0.1:1 to 0.25:1.
- 6. The process of claim 1 wherein the capping agent is selected from the group consisting of those that form chain ends with alkali metal-O or alkali metal-N bonds.
- 7. The process of claim 1 wherein the monomer is selected from the group consisting of butadiene, isoprene, and styrene.
- 8. The process of claim 7 wherein the monomer is butadiene or isoprene.
- 9. The process of claim 8 wherein the monomer is butadiene.
- 10. The process of claim 7 wherein the polymer is a polydiene diol.
- 11. The process of claim 10 wherein the polymer is a polybutadiene diol.
- 12. A gel-free process for making hydrogenated functionalized anionic polymers using a multi-alkali metal initiator which comprises:(a) anionically polymerizing at least one monomer with a multi-alkali metal initiator in a hydrocarbon solvent, (b) adding a trialkylaluminum compound before or during polymerization or before or at the same time as the capping agent, (c) capping the polymer by adding to the polymer a capping agent which, in the absence of the trialkylaluminum compound, would react with the polymer chain ends to form strongly associating chain ends wherein a polymer gel would be formed, (d) optionally terminating the polymerization by addition of a terminating agent, (e) washing the polymer with aqueous acid, and (f) hydrogenating the polymer with a hydrogenation catalyst.
- 13. The process of claim 12 wherein the initiator is a dilithium initiator.
- 14. The process of claim 12 wherein the acid is a mineral acid.
- 15. The process of claim 14 wherein the mineral acid is phosphoric acid wherein there is at least one mole of phosphoric acid per mole of alkali metal and at least three moles of phosphoric acid per mole of aluminum.
- 16. The process of claim 15 wherein the concentration of the acid in step (e) is from 20 to 40 percent by weight and the phase weight ratio of aqueous acid to polymer plus solvent is from 0.1:1 to 0.25:1.
- 17. The process of claim 12 wherein the capping agent is selected from the group consisting of those that form chain ends with alkali metal-O or alkali metal-N bonds.
- 18. The process of claim 12 wherein the monomer is selected from the group consisting of butadiene, isoprene, and styrene.
- 19. The process of claim 18 wherein the monomer is butadiene or isoprene.
- 20. The process of claim 19 wherein the monomer is butadiene.
- 21. The process of claim 18 wherein the polymer is a polydiene diol.
- 22. The process of claim 21 wherein the polymer is a polybutadiene diol.
Parent Case Info
This application claims the benefit of U.S. Provisional application Ser. No. 60/079,876, filed Mar. 30, 1998, the entire disclosure of which is hereby incorporated by reference.
US Referenced Citations (13)
Foreign Referenced Citations (1)
Number |
Date |
Country |
48-066678 |
Sep 1973 |
JP |
Non-Patent Literature Citations (2)
Entry |
“Solid-State NMR of Aromatic Polyamides,” by S. A. Curran, C. P. LaClair, and S. M. Aharoni, Macromolecules 1991, 24, pp. 5903-5909. |
Comprehensive Organometallic Chemistry , vol. 7, pp. 424-427, 1982. |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/079876 |
Mar 1998 |
US |