Improved mechanical and tribological properties of benzoxazine-bismaleimides resin by surface-functionalized carbon nanotubes

Surface-functionalized multiwall carbon nanotubes (ESi-MWCNTs) were obtained from hydrolysis of γ-(2,3-epoxypropoxy) propytrimethoxysilane to graft hyperbranched polysiloxane on the surface of multiwall carbon nanotubes (MWCNTs). The ESi-MWCNTs were then chosen as fillers to improve the mechanical and tribological properties of benzoxazine-bismaleimides (BOZ-BMI) resin. The influence of ESi-MWCNTs content on the mechanical and tribological properties of BOZ-BMI resin was researched. The results showed that suitable addition of ESi-MWCNTs can largely enhance the mechanical properties and decrease the frictional coefficient and wear rate of BOZ-BMI resin dramatically. The improvement of mechanical properties is due to the chemical reaction between BOZ-BMI and ESi-MWCNTs, which based on the analysis from fourier transform infrared (FTIR). The wear mechanism of the BOZ-BMI resin was converted from adhesive wear to abrasive wear after the addition of ESi-MWCNTs, observed from the wear surface of the materials by scanning electron microscopy (SEM). The thermogravimetric analysis (TGA) shows that the BOZ-BMI composite with 0.4 wt% ESi-MWCNTs exhibits the better thermal resistance, thus can inhibit the adhesive wear during the wear effective, which is correspond the tribological properties of composites.