Non-Isocyanate Synthesis and Application of Telechelic Polyurethanes via Polycondensation of Diurethanes Obtained from Ethylene Carbonate and Diamines

Aliphatic polyurethanes could be obtained in high yield via a non-isocyanate method based on the self-polycondensation of dihydroxyurethanes obtained by the reaction of diamines and ethylene carbonate. The polycondensation under a N-2 atmosphere yielded [6,2] polyurethane with a M-n value of 5300 in 87% yield. Two-step polycondensation, consisting of the polycondensation under a N-2 atmosphere followed by that under reduced pressure, was effective to improve the yield and the molecular weight up to 90% and 10,000, respectively. Although the second polycondensation step at 180 degrees C was accompanied by formation of urea groups, this side reaction was relatively suppressed at 150 degrees C. The resulting polyurethane having hydroxyl groups at both of the end groups was converted to polyurethane methacrylate via a reaction with glycidyl methacrylate, and the polyurethane methacrylate served as a crosslinker for radical polymerization of methyl acrylate. (C) 2012 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 525-533