Inspiration from diatoms: Silication-oxidation of fibre-reinforced epoxy composite for strengthening, toughening, corrosion resistance, UV-aging resistance, and flame retardancy

Abstract

Owing to the permanent failure derived from stress cracking, atrocious weather, and combustion of fibre-reinforced polymeric composites (FRPC) under harsh service conditions, the multifunctionalisation of FRPC has become increasingly crucial, particularly for three or more traits. Inspired by diatoms that exhibit prominent mechanical strength, corrosion resistance, and ultraviolet (UV) aging resistance owing to the protection of the silicon-oxygen framework, silication-oxidation modification of FRPC was performed to achieve multi-functionalisation in a simple and high-efficiency manner. Specifically, a continuous basalt-fibres fabric was used as a continuous framework for the composite to mimic the inorganic silica that constitutes diatoms, and a novel epoxy silicate resin consisting of organic silicon and carbon chains is synthesised via a topological strategy as the body of the composite, which is similar to the organic matter in diatoms. Interestingly, with the construction of diatom-like components and structures as well as the regulation of the thermosetting network topology, the performance of the resin matrix and interface is enhanced, thus endowing the composite with outstanding strength, toughness, corrosion resistance, UV-aging resistance, and flame retardancy. This diatom-inspired silication–oxidation strategy provides a simple and efficient method for preparing a multifunctional FRPC for application in the fields of shipbuilding and ocean engineering.