Synthesis and Properties of Networked Polyhydroxyurethanes by Polyaddition of Novolac Type Cyclic Carbonate with Diamines

Abstract

Recently, five-membered cyclic carbonates produced by the reaction of epoxide and carbon dioxide have been reported as an important monomer for functional polymer. In this study, multi-functional five-membered cyclic carbonate(CNC) was synthesized from o-cresol novolac glycidyl ether and carbon dioxide under atmospheric pressure in high yield. In addition, novel networked polyurethanes with hydroxyl groups (PHUs) were prepared by the polyaddition of CNC with various aliphatic diamines as hardener. PHUs were cast as flexible transparent and brown films. The glasstransition temperatures of PHUs were in the range from 107 to 133℃, which were lowered with increasing methylene chain length of diamines. Furthermore, the 5% weight loss temperatures of PHUs were relatively low, 249－296℃, because of decomposition and recombination of urethane linkage. Moreover, in the thermal decomposition of PHUs, it was confirmed that urethane linkage was preferentially decomposed to give urea linkage as previously reported.