Study on thermo-oxidative stability of nano-SiO2/bismaleimide composite

The effects of prepolymer molecular weights on the thermal stability of nano-bismaleimide composite materials were studied in this paper. A series of composites with different prepolymer molecular weights are prepared by polymerizing nano-SiO₂, chopped carbon fiber and bismalemide resin. Nano-composites are characterized by dynamic mechanical analysis and weight loss measurements after the short-term isothermal exposure. The results indicate that for the composite prepared from prepolymers with lower molecular weight, activation energy for oxidative degradation is decreased, resulting in higher total weight loss in short-term isothermal aging.