High strength, stable and self-healing copolyimide for defects induced by mechanical and electrical damages

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2022-08, Vol.1 (31), p.1137-11315
• Main Authors: Wan, Baoquan, Dong, Xiaodi, Yang, Xing, Zheng, Ming-Sheng, Chen, George, Zha, Jun-Wei
• Format: Article
• Language: English
• Subjects: Copolymerization; Damage; Diamines; Glass transition temperature; Insulation; Modulus of elasticity; Thermal stability
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d2tc01605b

Self-healing of damage is a common phenomenon in organisms but is hardly ever encountered in rigid polymer materials. For next-generation electricals and electronics, it is crucial to accurately mimic organisms to detect and heal mechanical/electrical damage. Herein, disulfide bond exchange is designed to introduce the self-healing ability in a copolymerized polyimide (copolyimide). A copolyimide insulation film with two diamine monomers is successfully prepared, which also possesses good self-healing ability after being mechanical/electrical damaged. Furthermore, the self-healing copolyimide film still maintains its good Young's modulus ( E ) >4 GPa, high thermal stability with glass transition temperature ( T g ) >190 °C, and excellent insulation property with breakdown strength ( E b ) >300 kV mm −1 . The combination of the simple copolymerization and unique self-healing ability is suitable for high T g polyimide to make this an ideal method for insulation field. A copolyimide (CPI) was prepared by a simple copolymerization process. The film possesses good self-healing ability based on disulfide bond exchange after mechanical/electrical damage and maintains high thermal stability and insulation property.