Single component epoxy systems used for enhanced electrical performance and applications

Single-component epoxy resin-based systems can be used in a variety of applications including those for high voltage solventless electrical insulating varnishes as well as for casting systems for coils, insulators and bushings. Other important applications include those of reinforced composites and laminates for a wide variety of electrical and structural applications. Their inherently high electrical resistance and low electrical dissipation, coupled with high mechanical strength under wet and high humidity conditions, provide the necessary properties for use in motor windings, wire and cable coatings, filament wound and pultruded structures and laminates. Compared to other impregnating systems (e.g. unsaturated polyesters) their very low volatile contents are remarkable. This paper reports on systems that are cured with classical Lewis acid/amine complexes as well as on new systems that are cured by a radical/cationic mechanism.