Carbodiimide-Assisted Synthesis of High Purity Bis(cyclic carbonate) Under Atmospheric Conditions for Preparation of Non-Isocyanate Polyurethane

Abstract

The cyclic carbonates as non-isocyanate polyurethane (NIPU) precursors are usually prepared via CO2 fixation under harsh conditions for a satisfactory conversion rate, which is energy-intensive. Herein, cyclic carbonate was prepared under ambient conditions with high purity and yield using a water-soluble ethyl-(N′,N′dimethylamino) propylcarbodiimide hydrochloride (EDC) to provide a favored industrialization method. The glycerol carbonate was reacted with a furan-based dicarboxylic acid using EDC to evolve cyclic carbonates, followed by the aminolysis with different chemical structural amines to produce bio-based NIPUs. The effects of the reaction parameters on the yield and purity of bis(cyclic carbonate) were investigated. The results showed that the synthesized bis(cyclic carbonate) have a purity of 99% and a yield of > 70%. The different structures of the diamines exhibited different reactivity and molecular weights in the order of multi-functional amine > linear amine > cyclic amine. All the synthesized furan-based NIPUs presented excellent thermal stability above 350 °C and glass transition temperature in the range of 51.9 °C to 99.6 °C. The result demonstrates the potential of this environmentally benign strategy to prepare high-performance bio-based NIPUs with interesting properties even for biomedical applications.