Hyperbranched polysiloxane-modified UV-curable graphene conductive coatings: preparation and characterization

Abstract

A new UV-curable hyperbranched silicone epoxy acrylate resin was synthesized, and two kinds of carbon-based components, graphite and graphene, were applied as conductive materials. An ultraviolet-curing coating was successfully synthesized with using epoxy acrylate (EA) as oligomer, butyl acrylate (BA), and hyperbranched polysiloxane (HPSi) as monomers, benzoin dimethyl ether (DMPA), and benzophenone (BP) as photo-initiators, triethanolamine (TEA) as photo-activator, and other auxiliaries. In this work, the UV-curing efficiency and cured performance, together with the effect of different conductive fillers and the amount of conductive filler on the integrated performance of the composites, are investigated. The results show that as the HPSi content increases, the curing time is shortened. At the addition amount of 7.5%, it reaches the best conductivity, and at the addition amount of 10%, the corrosion resistance after curing is the best. However, the maximum tensile strength of 10.4% is obtained at 0.75 graphene. The FE-SEM micrographs of the UV-curable conductive coating show that with increasing incorporation of graphene into the substrate, the fractured surface of a rough surface changes to smooth one. Thermal properties of the films investigated using TGA curves indicate that graphene-doped conductive adhesive film (315.1 °C) possesses much higher heat resistance than that of graphite-doped conductive adhesive film.