Design of near-infrared responsive self-healing photocured polyurethane materials with thiourethane bonds

Abstract

In this work, a photopolymerizable polyurethane oligomer (PETU) with thiourethane bonds was designed and synthesized. Afterwards, the near-infrared responsive self-healing polyurethane films (PETU-HI-X) were fabricated by photopolymerization using homemade PETU, polydopamine (PDA), and commercially available isobornyl acrylate (IBOA) and 2-hydroxyethyl acrylate (HEA). PETU-HI-X have good photopolymerization and photothermal conversion performance. The as-prepared near-infrared responsive self-healing polyurethane polymer PETU-HI-1.0 exhibited a tensile stress of 1.06 MPa, strain of 1021 %, initial decomposition temperature of 290 °C. In addition, the temperature of the material can rise to more than 100 °C after irradiation with near-infrared light for 3 min, showing excellent photothermal conversion performance, based on which the material shows more than 90 % self-healing efficiency after irradiation with near-infrared light for 30 min. More importantly, the near-infrared responsive self-healing polyurethane polymer PETU-HI-1.0 also has an excellent degradation property. The self-healing polyurethane films have also been used to prepare the flexible electronic device that can be healed and fully restored their conductivity after getting damaged.