Flexible, high temperature resistant and highly efficient E-heating graphene/polyimide film

Carbon/polymer-based flexible electrothermal films, as a Joule heating material with excellent electrothermal properties, good formability, and lightweight, are a very needed material in aircraft wing de-icing systems, flexible electric heating elements, and low-voltage wearable devices. In this study, a series of flexible electrically heated films were successfully prepared using polyimide (PI) as the film-forming substrate and graphene (GE) as the conductive filler. The effects of graphene content on the morphology, microstructure, and electrothermal properties, as well as the mechanical flexibility of the electrothermal films, were systematically investigated. The results showed that the GE/PI electrothermal films not only retained the good electrical conductivity of graphene but also had the excellent mechanical properties and high heat resistance of polyimide. The electric heating film with the addition of 8 wt. % GE can quickly reach 390 °C at 24 V with uniform temperature distribution, and the mass loss at 500 °C is only 0.98 wt. %. A wide range of applications exist in fields such as flexible electric heating elements.