  Bismaleimide(BMI) resin/silsesquioxane or titania nanocomposites were
synthesized from bismaleimide resin and SiO3/2 or TiO2 via the sol-gel process
of N-{\gamma}-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.
