SELECTIVE CATALYTIC PROCESS FOR PREPARING N-HALOTHIOSULFONAMIDE MODIFIED TERPOLYMERS AND CATALYSTS THEREFOR

摘要

Preparation of halothio-sulfonamide-modified terpolymers having a low degree of unsaturation is accomplished by preferably reacting N-chlorothio-sulfonamide with an ethylene-(alpha-olefin)-diene monomer terpolymer comprising for example, 1,4-hexadiene and/or dicyclopentadiene, in the presence of a catalyst comprising a salt of the formula MAn, where A is an anion or mixture of anions of a weak acid, and M is a metal selected from copper, antimony, bismuth, tin, zinc, and iron, and n is a number which corresponds to the oxidation state of M divided by the valence of said weak acid anion. The reaction is preferably carried out in a melt phase process. When M is zinc or iron, it is preferred to use the salt in combination with a second metal salt of a weak acid wherein the metal is selected from the groups consisting of nickel, chromium, and Group IIA metals. Mixtures of such modified terpolymers with highly unsaturated rubbery polymers and vulcanizates of such mixtures are particularly useful in pneumatic tire sidewalls.