Discovery and Development of Epichlorohydrin Elastomers

The epichlorohydrin elastomers were discovered in early 1957 when the author's new vinyl ether coordination catalyst was explored for epichlorohydrin polymerization and yielded a new rubber, amorphous polyepichlorohydrin. This work quickly led to the discovery of unique new organometallic catalysts which facilitated the development of the epichlorohydrin elastomers. Laboratory studies indicated that amorphous polyepichlorohydrin had merit as a specialty oil resistant elastomer. Limited market contacts on amorphous polyepichlorohydrin (called chlorohydrin rubber or CHR) with rubber producers, users, and epichlorohydrin producers indicated some problems and some interest. We made progress in solving the problems but Hercules decided not to proceed with the development at that time. Instead, Hercules know-how and patents were licensed to B. F. Goodrich Chemical Company. We subse quently made larger samples of epichlorohydrin—ethylene oxide copolymers and found the 1:1 mol copolymer to be an outstanding candidate with greatly improved low- temperature and other rubber properties, and with no sacrifice in oil resistance. A process was developed and scaled up to a 500-gallon reactor to provide large samples for further study. Goodrich announced commercialization of the epichlorohydrin elastomers in October 1965 under the trademark Hydrin.