Enhanced ultra violet resistance of epoxy nanocomposites filled with liquid-like graphene oxide/silicon dioxide nanofluid

The ultra violet (UV) resistance of epoxy resins has been paid more and more attention, and the development of highly efficient UV resistant materials is critical. Therefore, we showed liquid-like graphene oxide (GO)/silicon dioxide (SiO₂)-based derivatives for UV resistance of epoxy resins. To be specific, SiO₂ nanoparticles were deposited in situ on the surface of GO. Subsequently, a black, homogeneous and solvent-free GO/SiO₂ nanofluid was prepared by grafting organosilanes (KH560) and polyetheramines (M2070) on the surface of GO/SiO₂. Furthermore, the solvent-free GO/SiO₂ nanofluid/epoxy resin composites were also prepared. The bending properties before and after UV irradiation of the nanocomposites at room temperature were investigated to reveal the role of the interphase. The toughening mechanism of GO/SiO₂ nanofluid was elucidated by observing the fracture surface. As expected, the loss of bending strength of the resin resulting from UV illumination was efficiently reduced by the GO/SiO₂ nanofluid. This may be attributed to the excellent anti-UV aging properties of GO and SiO₂ nanoparticles. Moreover, the GO/SiO₂ nanofluid can provide excellent bending resistance for epoxy resin both before and after illumination, owing to its great compatibility with epoxy resin by organic chains and hindrance to crack propagation by nano cores.