Controlled synthesis of aliphatic polycarbonate diols using dimethyl carbonate and various diols

Abstract

AbstractPolycarbonate diols (PCDLs) are mainly used as soft segments for the synthesis of high‐performance polyurethanes. In this work, dimethyl carbonate (DMC) and aliphatic diols are selected as reactants and CH3COONa is used as a catalyst to synthesize a series of PCDLs with different structures and different molecular weights by ester exchange polymerization reaction. The chemical structures of the PCDLs are characterized by FT‐IR, 1H NMR, and 13C NMR, and the components of the distillates in the ester exchange stage are analyzed by gas chromatography. Due to the azeotropic problem of DMC and by‐product methanol during the ester exchange process, It is difficult to design and control the reactions of PCDLs to obtain the target molecular weight products. Based on the reaction process of PCDLs, we proposed a method to design and synthesize the target molecular weight of PCDLs by using the reaction molar ratio of DMC and aliphatic diols involved in the transesterification reaction, which is not affected by the conditions of transesterification reaction and is applicable to the reactions of DMC with various diols.