▎ 摘　　要

NOVELTY - Preparation of nano-silica modified graphene oxide/epoxy resin composite material involves (i) dispersing the nano-silica in a mixture of absolute ethanol and water to obtain nano-silica dispersion, (ii) adding a silane coupling agent to the nano-silica dispersion to obtain reaction liquid (I), (ii) washing the reaction solution (I) and vacuum drying to obtain silane-functionalized nano-silica, and (iii) dispersing the nano-silica grafted with graphene oxide and hyperbranched polymer in N,N-dimethylformamide, ultrasonically processing to obtain mixture (I), adding the initiator to the mixture (A), stirring and refluxing at 70-80 degrees C for 4-6 hours to obtain reaction solution (IV), using N,N'-dimethylformamide to wash the reaction solution (IV) 3-4 times and vacuum drying to obtain graphene oxide-nano-silica hybrid material, and adding the graphene oxide-nano-silica hybrid material to acetone to obtain a graphene oxide-nano-silica hybrid material solution. USE - Preparation of nano-silica modified graphene oxide/epoxy resin composite material used for surface modification of graphene oxide. ADVANTAGE - The prepared nano-silica modified graphene oxide/epoxy resin composite material has excellent mechanical properties of epoxy resin and filler-reinforced epoxy resin, strength, and enhancement effect than pure graphene oxide or nano-silica. DETAILED DESCRIPTION - Preparation of nano-silica modified graphene oxide/epoxy resin composite material involves (i) dispersing the nano-silica in a mixture of absolute ethanol and water and ultrasonically processing to obtain nano-silica dispersion, (ii) adding a silane coupling agent to the nano-silica dispersion, stirring and refluxing for 6-8 hours at a constant temperature of 70-80 degrees C to obtain reaction liquid (I), (ii) washing the reaction solution (I) and vacuum drying to obtain silane-functionalized nano-silica, dispersing the silane-functionalized nano-silica in a mixture of methanol and water, ultrasonically processing to obtain the silane-functionalized nano-silica dispersion, adding N,N'-methylenebisacrylamide to the silane-functionalized nano-silica dispersion and stirring and refluxing for 18-24 hours at a constant temperature of 40-50 degrees C to obtain reaction solution (II), adding the diethylenetriamine to the reaction solution (II), refluxing for 18-24 hours under constant temperature, stirring at 40-50 degrees C to obtain the reaction solution (III) and washing the reaction solution (III), vacuum drying to obtain nano-silica grafted with hyperbranched polymer, and (iii) dispersing the nano-silica grafted with graphene oxide and hyperbranched polymer in N,N-dimethylformamide, ultrasonically processing to obtain mixture (I), adding the initiator to the mixture (A), stirring and refluxing at 70-80 degrees C for 4-6 hours to obtain reaction solution (IV), using N,N-dimethylformamide to wash the reaction solution (IV) three to four times and vacuum drying to obtain graphene oxide-nano-silica hybrid material, and adding the graphene oxide-nano-silica hybrid material to acetone, ultrasonically processing to obtain a graphene oxide-nano-silica hybrid material solution, adding epoxy resin to the graphene oxide-nano-silica hybrid material solution, ultrasonically processing and drying to obtain an epoxy resin mixture, adding curing agent to the epoxy resin mixture, mechanically stirring, and drying to obtain the epoxy resin mixture at 80-90 degrees C and having vacuum degree of (-30)-(35) kPa, pouring the epoxy resin mixture into the preheated molding at 80-90 degrees C in the drying box and curing.