Synthesis and Properties of Renewable Nonisocyanate Polyurethanes (NIPUs) from Dimethylcarbonate

Novel fully renewable AA-BB type nonisocyanate polyurethanes (NIPUs) were synthesized using the transurethanization approach. Dicarbamate monomers were prepared by the reaction of a diamine with an excess of dimethylcarbonate (DMC), in presence of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as catalyst. Then, the dicarbamate was reacted with a diol to afford the polymer, in presence of TBD or K2CO3 as catalyst. Several renewable diamines and diols were tested. The two steps were conducted under neat conditions. The obtained materials exhibited T-g values varying from -38 to 42 degrees C, T-m values varying from 42 to 204 degrees C, and thermal stabilities above 200 degrees C. (c) 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1351-1359