On the mechanism of the alternate copolymerization of phenyl isocyanate with ethylene oxide

Abstract

Abstract The mechanism of the alternate copolymerization of phenyl isocyanate with ethylene oxide was investigated. Several experimental results show that this copolymerization proceeds according to an anionic coordinated mechanism. As for alternate copolymerization three mechanisms are generally considerable as follows; (1) a simple copolymerization, (2) a polymerization through an equimolar cyclic intermediate, (3) a successive alternate coordination. The present paper describes the studies concerned with each case. The experimental result in the elementary model reactions seems to be compatible with the mechanism of the successive alternate coordination. In addition, it was also found that only the monomeric form of the catalyst is effective to the alternate copolymerization.