Recyclability and Self‐Healing of Dynamic Cross‐Linked Polyimide with Mechanical/Electrical Damage

• Published in: Energy & environmental materials (Hoboken, N.J.) N.J.), 2023-01, Vol.6 (1), p.401-n/a
• Main Authors: Wan, Baoquan, Zheng, Ming‐Sheng, Yang, Xing, Dong, Xiaodi, Li, Yuchao, Mai, Yiu‐Wing, Chen, George, Zha, Jun‐Wei
• Format: Article
• Language: English
• Subjects: Covalent bonds; Damage; Electric power; electrical damage; Energy consumption; Glass transition temperature; Healing; Heat resistance; High temperature; Imines; Insulation; Mechanical properties; Modulus of elasticity; polyimide; Polyimide resins; Polymers; Recyclability; Recyclable materials; self‐healing; Tensile strength; Thermal stability; Transition temperatures
• ISSN: 2575-0356; 2575-0348; 2575-0356
• DOI: 10.1002/eem2.12427

Recyclability and self‐healing are two most critical factors in developing sustainable polymers to deal with environmental pollution and resource waste. In this work, a dynamic cross‐linked polyimide insulation film with full closed‐loop recyclability is successfully prepared, which also possesses good self‐healing ability after being mechanical/electrical damaged depending on the Schiff base dynamic covalent bonds. The recycled and self‐healed polyimide film still maintain its good tensile strength (σt) >60 MPa with Young's modulus (E) >4 GPa, high thermal stability with glass transition temperature (Tg) >220 °C, and outstanding insulation property with breakdown strength (E0) >358 kV mm−1, making it a very promising low energy consumption and high temperature resistant insulation material. The strategy of using Schiff base dynamic covalent bonds for reversible repairing the structure of high Tg polyimides promotes the wider application of such sustainable and recyclable material in the field of electrical power and micro‐electronics. A recyclable and self‐healing polyimide (RSPI) film was successfully synthesized through the polymerization of amino terminated polyimide prepolymer (ATPP) and benzene‐1,3,5‐tricarboxaldehyde (BTA). The RSPI film possesses excellent recyclability and good self‐healing ability based on the Schiff base dynamic covalent bond after mechanical/electrical damage. Moreover, the RSPI film still maintains high thermal stability and insulation property.