PROCESS FOR SULPHONATING POLYSULPHONES

摘要

A process for the sulphonation of a polysulphone having recurring units of the formula
-Ph-SO2-Ph-O- (III)
wherein Ph is 1,4-phenylene, comprises suspending the polysulphone, in the form of a polymer/solvent intercrystalline solid, in a fluid, chlorinated hydrocarbon; and reacting the suspended polysulphone with a sulphonating agent at from -50 to +80 DEG C; in which the amount of the sulphonating agent is such that there are from 0.4 to 5 atoms of sulphur in the sulphonating agent per atom of sulphur in the sulphonated product.