Ring-opening polymerization of trimethylene carbonate by calix[8]arene-neodymium

Ring-opening polymerization of trimethylene carbonate (TMC) with a rare ear th calixarene compound as catalyst has been studied for the first time. The effect of TMC/Nd (molar ratio) and polymerization conditions were investig ated in detail. It was found that calix[8]arene-neodymium is a highly effec tive catalyst for the bulk polymerization of TMC and gives high molecular w eight (M-v = 60,000) polymer. The optimum conditions of TMC polymerization were found to be as follows:TMC/Nd (molar ratio) = 2,000, 80 degrees C, 16 h. The polymers were characterized by NMR, GPC and DSC. Studying the mechan ism by NMR showed that the polymerization of TMC catalyzed by calix[8]arene -neodymium proceeds via a cationic mechanism.