Conjugated diene polymers and copolymer blocks and process for preparing same
AssigneeKraton Polymers U.S. LLC
InventorCarl L. Willis
Life of this patent
Estimating the term…
Abstract
Disclosed is a process for preparing polymers and copolymer blocks of conjugated dienes with varying amounts of branching comprising the use of a microstructure control agent and a microstructure control agent deactivant. The polymerization can be started with or without a microstructure control agent. At some point in the polymerization prior to the completion of the addition of the conjugated diene to the polymer, the microstructure control agent can be deactivated, either partially or completely, resulting in a polymer or copolymer block having a region of less branching adjacent to a region of more branching. Preferred microstructure control agent deactivants are metal alkyls such as triethyl aluminum.
Claims16
A process for preparing a conjugated diene polymer or copolymer block having a varying amount of branching comprising combining:
- (a) an anionic polymerization site;
- (b) a conjugated diene monomer;
- and
- (c) a microstructure control agent;
- under reaction conditions sufficient to form a living polymer admixture and, at a point in the process prior to the completion of the polymerization of the conjugated diene monomer, combining the living polymer admixture with a microstructure control agent deactivant to mitigate or eliminate the effect of the microstructure control agent, wherein the microstructure control agent deactivant is an aluminum alkyl compound having from 1 to 20 carbon atoms per alkyl substituent and mixtures thereof.
Dependencies are inferred from the claim text.