Diimide as a reagent for the hydrogenation of unsaturated polymers

Abstract

Abstract The hydrogenation of various butadiene polymers and of polyisoprene with diimide generated in situ from p ‐toluenesulfonylhydrazide was investigated. The best results were obtained when concentrated polymer solutions were heated with a five‐fold excess of p ‐toluenesulfonylhydrazide. Complete hydrogenation of all polymers was obtained under such conditions, but some 1,2‐butadienyl units were found to contain fragments derived from p ‐toluenesulfonylhydrazide. Diimide seems to be a good reagent for hydrogenating unsaturated units in polymers, but mild conditions for generating it are needed if side reactions are to be avoided.