Method for preparing cross-linked vinylaromatic polymers containing nitro groups

摘要

The method for preparing cross-linked vinylaromatic polymers containing nitro groups having the general formula <IMAGE> where R' is H, NO2, COOH, SO3H, P(O)(OH)2, or P(O)H(OH), m is from 60 to 99 and n is from 40 to 1, consists in treatment of the starting cross-linked polymers having the general formula <IMAGE> where R is H, COOH, SO3H, P(O)(OH)2, or P(O)(OH), m is from 60 to 99 and n is from 40 to 1, with a mixture of an alkali metal nitrate and an acid agent, at a temperature from -5 DEG to 95 DEG C. The quantity of the alkali metal nitrate in the nitrating mixture is from 0.1 to 8 moles per mole of the starting cross-linked polymer. The method provides conditions for preparing cross-linked vinylaromatic polymers, containing nitro groups, having higher mechanical strength, high osmotic stability, and their volume in an ion-exchange column changes insignificantly as acid media are changed for alkaline, and vice versa.