Nanocomposite coatings for high temperature insulation of electrical wires

Organic polymers and inorganic materials (ceramics / glasses) are both electrical insulators, widely used in different applications according to their inherent nature. Polymers possess high dielectric strength and mechanical flexibility, thus are usually applied to conductor wire insulation, whilst ceramics have very high temperature stability but mechanical brittleness, and hence are mostly used in applications where high temperature is essential while mechanical flexibility is not. For wire insulation, polymers place an up-limit on service temperature, with the highest temperature rating being 240°C at present market from polyimide enamelled wires, e.g. NEMA MW16-C. There is, however, a significant design need for flexible and versatile insulation materials capable of operating at temperatures well above polymer insulation, particularly for some emerging technologies such as more electric aircraft and downhole applications [1,2]. This work presents a type of nanocomposite coatings for wire insulation to offer excellent thermal stability far beyond polymer enamels can reach whilst maintains moderate flexibility