Synthesis of non‐isocyanate polyurethanes with high‐performance and self‐healing properties

Abstract

Due to the utilization of the potentially hazardous monomer, isocyanate compound, polyurethanes (PUs) with good properties are restricted in several fields, such as bio‐engineering. Non‐isocyanate polyurethanes (NIPUs) with high overall performance and self‐healing properties were synthesized by dicarbamate, bio‐based isosorbide (IS) and polycarbonate diols (PCDLs) through a solvent‐free and ecologically friendly melt polycondensation route. Previously, few bio‐based monomers have been introduced into polycondensation reactions of PUs. Chemical structures of NIPUs were analyzed by Fourier transform‐infrared spectroscopy (FT‐IR), proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC). With changing the IS content and the molecular weight of PCDL, the obtained NIPUs had linear structures and high molecular weights ranging from 3.3 × 104 to 5.9 × 104 g/mol. Results of tensile testing, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) suggested NIPUs had well thermal and mechanical properties, with Td,5% above 286.2°C and tensile strength between 8.0 and 16.7 MPa due to the crystallization and the hydrogen bonding interactions. Furthermore, the NIPUs exhibited self‐healing ability and recyclability, having great potential for industrialization.