Abstract A substrate is one critical factor for the wide application of flexible displays and electronic packaging materials in the future. Polyimides with high optical transparency, good thermal stability, dielectric properties, and nice mechanical properties are significant in substrates. A simple and feasible method to modify transparent polyimide films is to blend them with inorganic fillers. In this work, we successfully modified the transparent films by using phenyltriethoxysilane to synthesize trisilanol phenyl polyhedral silsesquioxane and adding it to the films. The introduction of trisilanol phenyl polyhedral silsesquioxane into the copolymer films resulted in the increase of high-temperature dimensional stability, optical performance, and mechanical properties of the films. The sample containing 5% of trisilanol phenyl polyhedral silsesquioxane exhibited a glass transition temperature of 322°C, coefficient of thermal expansion of 41.4 ppm/K, and tensile strength of 127 MPa, and the transmittance at 450 nm has reached 83.5%.
Novel organic-inorganic composites were in-situ synthesized by using TriSilanolPhenyl polyhedral oligomeric silsesquioxane (SO-POSS) as fillers and poly(2,5-benzimidazole) (ABPBI) as polymer matrix. The uniformly dispersed 3% SO-POSS particles in ABPBI matrix increased the thermal stability of the composite membranes. It was found that both the water and H 3 PO 4 uptakes were increased significantly with the addition of SO-POSS due to the formation of hydrogen bonds between the POSS and H 2 O/H 3 PO 4 , which played a critical role in the improvement of the conductivity of the composite membranes at temperature over 100 °C. Proton conductivities of H 3 PO 4 doped with 3wt% SO-POSS contained ABPBI membranes increased with the increase of H 3 PO 4 absorbance, reaching the maximum proton conductivity of 2.55 × 10 -3 S·cm -1 at 160 °C, indicating that the ABPBI/SO-POSS composite membrane could be a promising candidate for mid-temperature PEMFCs.
危险品化学品经营许可证（带存储）