Preparation of mechanically tunable non-isocyanate polyurethane based on thiol-ene click reaction and amine structure

Abstract Non-isocyanate polyurethane (NIPU) is one of the hot spots in the scientific research of polyurethane. In this work, mechanically regulable NIPU were prepared by ring-opening polymerization of cyclic carbonates via diamines. Cyclocarbonates with different functionalities were firstly synthesized by thiol-ene click reaction, which was characterized through nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy (FITR). Subsequently, the controllable performance of NIPU films were obtained by using diamines with different structures. The mechanical and thermal properties of prepared NIPU films were studied by swelling experiment, differential scanning calorimetry (DSC), tensile test and thermogravimetric analysis (TGA). Experimental results suggested that the control of functionality and reactivity endowed the material with an adjustable crosslinking density. The Young's modulus of the material could be regulated from 51.31 MPa to 765.07 MPa. Furthermore, the studied films also showed good thermal stability.