Room-temperature self-healable and recyclable polythiourethane film with excellent mechanical properties based on double dynamic covalent bonds

Abstract

Currently, it remains a challenge to find an appropriate dynamic interaction to prepare elastomers which perfectly match the general properties of the target material with self-healing and recyclability properties. Herein, a room-temperature self-healable polythiourethane with excellent mechanical properties and recyclability has been development. Based on the boronic ester transesterification and thiourethane exchange macrophase separation, polythiourethane can achieve complete self-healing at room temperature after 36 h in the absence of external stimuli. More importantly, PTU-B7 has a good tensile strength of 9.58 MPa, a toughness of 35.8 MJ/m3 as well as a fracture strain of up to 735 %. At a relatively low temperature (60 °C), small pieces can be hot pressed for a short time to form a homogeneous block for reprocessability. The ability to self-repair under mild conditions while still having good mechanical strength makes the material a promising application and provides new ideas for the study of self-healing polymers.