Patent ID: 8835562
Filing Date: 2014-09-16
Classification: C08F,C08G,C08L

Abstract:
1. A process for preparing sulfonated block polymers in non-halogenated aliphatic solvents, comprising the steps of: providing a precursor block polymer having at least one end block A and at least one interior block B wherein each A block is a polymer block resistant to sulfonation and each B block is a polymer block susceptible to sulfonation, wherein said A and B blocks are substantially free of olefinic unsaturation; and reacting the precursor block polymer with an acyl sulfate in a reaction mixture further comprising a first non-halogenated aliphatic solvent and a second non-halogenated solvent to form a sulfonated block polymer, wherein the precursor block polymer is substantially soluble in the first non-halogenated aliphatic solvent and the B block is substantially insoluble in the second non-halogenated aliphatic solvent, and wherein the initial concentration of the precursor block polymer is in the range of from about 0.1 wt % to a concentration that is below the limiting concentration of the precursor block polymer based on the total weight of the reaction mixture.