Patent ID: 8952126
Filing Date: 2015-02-10
Classification: C08G

Abstract:
1. A method of purifying a block copolymer comprising: heating a solution containing a crude block copolymer and an alcohol; cooling the solution to promote precipitation of a purified block copolymer; and isolating the purified block copolymer, wherein isolating the purified block copolymer comprises filtering the solution to separate the purified block copolymer from a filtrate and recovering unreacted monomer and catalyst from the filtrate, and further wherein: an amount of impurities remaining in the purified block copolymer is from about 0 to about 5 wt % based on a total weight of the purified block copolymer; a ratio of a polydispersity index of the crude block copolymer to a polydispersity index of the purified block copolymer is from about 1.02 to about 1.25; a ratio of a molecular weight of the crude block copolymer to a molecular weight of the purified block copolymer is from about 0.75 to about 1.0; and a ratio of a number average molecular weight of the crude block copolymer to a number average molecular weight of the purified block copolymer is from about 0.65 to about 1.