Polyimide-quartz hybrid compositions: Segmental dynamics and thermal stability

The segmental dynamics and thermal stability of polyimide-quartz hybrid mat erials containing covalently bound nanophases were studied by differential scanning calorimetry, laser-interferometric creep rate spectroscopy, and th ermogravimetry. The presence of silica nanoclusters partly or completely su ppresses segmental mobility in the polymer phase, the effect being most pro nounced in the region of the polymer glass transition temperature, and enha nces the small-scale mobility at temperatures below 330 K. This leads to a considerable increase in the effective activation energy of thermooxidative degradation and in the thermal stability of the hybrid composition.