Highly Self-healable Polyurethane/Polyimide Blends with Improved Mechanical Properties

Abstract

A new self-healable polymeric material is prepared by solution blending of conventional polyurethane and functional polyimide. The polymer blend has outstanding self-healing abilities and, interestingly, significantly increased surface hardness and modulus compared with conventional polyurethane only, which is attributed to the strong supramolecular networks resulting from interactions between urethane groups and imide groups. Fourier-transform infrared spectroscopy is applied to prove the effective self-healing mechanism of self-healable polymer blend, and a nanoindentation tester and a universal tensile machine are used to compare the mechanical properties of self-healable polymer blends and conventional polyurethane after the self-healing process. The self-healable polymer prepared in this study exhibits excellent self-healing capabilities and mechanical properties, and therefore can be used for practical applications like automotive coatings and electronic devices.