Synthesis and Characterization of Hybrid Silica/Polyimides Obtained by Sol-Gel Processing

Abstract

This work reports the synthesis and characterization of some hybrid silica/polyimides obtained by the sol-gel process. These hybrids present good thermostability with the degradation process starting above 470°C. The glass transition temperatures of the hybrids are slightly higher than that of the pure polyimide film, while dynamic contact angles are lower than that of the pure polyimide. The experiments show that increasing the silica content improves the thermal stability and decreases the dielectric constant of the hybrid polyimide films. Moreover, increasing the silica content leads to a higher rigidity of the hybrid polyimide films, as was proved by dynamic mechanical analysis, and to a slight decrease of the dynamic contact angles.

Keywords:

• dielectric constant
• hybrid film
• polyimides
• sol-gel

Notes

^aMaximum advancing contact angle value;

^bMinimum receding contact angle value;

^ccontact angle hysteresis; H = θa − θr.