Attaching SiO2 nanoparticles to GO sheets via amino-terminated hyperbranched polymer for epoxy composites: Extraordinary improvement in thermal and mechanical properties.

[Display omitted] • A new strategy for preparing GO-SiO 2 hybrids via amino-terminated HBP was developed for the first time. • The HBP on the SiO 2 surface not only reacted better with the groups on GO surface, but also participated in the curing reaction of epoxy resin. • GO-SiO 2 /epoxy composites displayed higher mechanical and thermal properties than that of GO or SiO 2 composites. • The improvement was attributed to the synergistic effect among GO and SiO 2 and the strong interaction with the epoxy matrix. The deposition of nano-silica (SiO 2) on graphene oxide (GO) surface via amino-terminated hyperbranched polymer (HBP) was designed to improve the dispersion and interfacial interaction between GO and epoxy resin. The structures and morphologies of GO and GO-SiO 2 sheets were characterized by FT-IR, XRD, XPS, TG, SEM and TEM. Epoxy composites containing GO and GO-SiO 2 with 0.1 wt% loadings were prepared and systemically investigated. It was indicated that the GO-SiO 2 /epoxy composites displayed higher mechanical and thermal properties than that of GO or SiO 2 composites. For epoxy composites containing 0.1 wt% GO-SiO 2 , the flexural strength increased by 20.57% and 23.58% compared to that of individual GO composites and individual SiO 2 composites, respectively. Furthermore, the reinforcing mechanisms have been also illuminated. This work is expected to be beneficial to the designing of adhesive-bonded composite structures or components. [ABSTRACT FROM AUTHOR]