Dielectric and Structural Insight Into an Innovative Self-healing Copolymer

Polymer-based electrical insulations are an indispensable part of modern electrical devices. Unfortunately, the insulation systems are exposed to high mechanical and electrical stresses. Self-healing polymers have recently attracted attention in electrical engineering because of their ability to partially recover from mechanical and electrical damage to material in some cases. This paper presents a study of self-healing ethylene-anisylpropylene copolymers without and with the tert-butyl substituent in the phenyl ring, emphasising comparing the two materials regarding dielectric and structural properties. The study covers the full range of analytical techniques, including broadband dielectric spectroscopy, Fourier transform infrared spectroscopy, thermo-mechanical analysis and differential scanning calorimetry. This comprehensive approach has allowed in-depth investigation of their dielectric and structural properties, providing valuable insights into their performance and potential applications. Two tested copolymers exhibit exceptional dielectric properties, making them promising materials for various applications. The dielectric constant, loss factor and dissipation factor were evaluated, and the results showed that both materials met the requirements for practical use as either a rigid or stretchable insulator. However, the practical use of both materials is limited mainly by the glass transition temperature, around 8 °C for one material and 28 °C for the other. The dielectric and mechanical properties change rapidly when the glass transition temperature is exceeded.