Polymers of reduced specific viscosity between 0.05 and 3.0 dl/g, measured at 25 C. using a 1 percent solution in dioxane, which polymers contain substituted N-carbonyl sulfonyl'groups in their side chains and are composed of statistically distributed recurrent structural units of Formula I Formula lII' wherein R is a saturated aliphatic alkyl or alkoxy group each with one to six carbon atoms whic