Self-healable and mechanically reinforced polyurethane/titanium dioxide dielectric nanocomposites by exchangeable disulfide links

Flexible dielectric materials play an important role in the development of modern electronic technology. However, in harsh environments, dielectrics could be damaged by tearing, scratching, and hitting. If the material possesses self-healing ability, its service time could be greatly increased and related components and devices will then be better protected. In this paper, based on disulfide bond, a polyurethane/titanium dioxide composite with self-healing property was prepared. When the filler content is less than 5%, the average healing efficiency of mechanical properties reaches 80%, and the dielectric constant is increased by 1.64 times. This type of self-healing nanocomposites with improved mechanical and dielectric performances can be used as dielectrics in capacitors to prolong the service life of devices.