As one of a series of studies of 1, 4-addition type ring-opening polymerizations, the synthesis and ring-opening polymerization of N-substituted cyclic iminocarbonates have been studied. N-Alkyl and N-aryl cyclic iminocarbonates have been prepared by the reaction of sodium ethylene glycorate with the corresponding imidophosgenes. N-Halogeno cyclic iminocarbonates have been prepared from glycols, potassium cyanide and halogenes. ...