Silane functionalization of graphene oxide and its use as a reinforcement in bismaleimide composites

Silane-functionalized graphene oxide (GO) nanosheets were synthesized by chemically grafting gamma-methacryloxypropyltrimethoxysilane (MPTS) onto GO sheets. The resulting MPTS-functionalized GO (MPTS-GO) nanosheets were characterized by Fourier transform infrared spectroscopy, energy dispersive X-ray analysis, X-ray photoelectron spectra, X-ray diffraction, and Raman spectroscopy. Bismaleimide (BMI) composites filled with GO and MPTS-GO were prepared at different filler loading levels. The study showed that the exfoliation and dispersion of graphene sheets in BMI resin were significantly improved due to the surface functionalization effect. The tensile test indicated that the MPTS-GO/BMI nanocomposites showed higher tensile strength and modulus than the neat BMI resin and GO/BMI composites. Meanwhile, the impact strength of composites was also improved. The maximum increment of the tensile strength, tensile modulus, and impact strength of MPTS-GO/BMI nanocomposites were 22.17, 33.05, and 66.64 %, respectively. The fracture surface analysis revealed that the highly dispersed MPTS-GO nanosheets could trigger large-scale plastic deformation of resin matrix.