Novel Bismaleimide Resin/Silsesquioxane and Titania Nanocomposites by the Sol-Gel Process: the Preparation, Morphology, Thermal and Thermo-mechanical Properties

Bismaleimide(BMI) resin/silsesquioxane or titania nanocomposites were synthesized from bismaleimide resin and SiO3/2 or TiO2 via the sol-gel process of N-γ-triethoxylsilylpropyl-maleamic acid (TESPMA) or tetrabutyltitanate (Ti(OnBu)4, TBT), respectively, in the presence of the AP-BMI prepolymers. These nanocomposite materials were characterized by FT-IR, FE-SEM, TGA and DMA. It was found that the nano-scale SiO3/2 or TiO2 particles were formed in the AP-BMI resin matrix and the average original particle size of the dispersed phase in the nanocomposites was less than 100nm, but the particle aggregates with bigger size existed. Obvious improvements of Tg and the heat resistance of the AP-BMI resin were achieved by introduction of the nano-sized SiO3/2 inorganic phase, and the modulus at high temperatures was improved too. The incorporation of nano-scale TiO2 particles into the AP-BMI resin improved the Tg of the polymer, but lowered the thermal resistance of the material, and improved the modulus of the material at lower temperatures, but lowered the modulus at higher temperatures.