This study was performed primarily to investigate the effects of chemical modification on silica surface and
the silica content on the thermal and gas barrier properties of a polyethersulfone (PES) matrix. The PES/SiO2
composites composed of PES and three species of SiO2 nanoparticles (AEROSIL A200, R805 and R974) were
prepared by solution blending. The thermal behaviour, thermal stability, and morphology of the composites were
studied by DSC, TGA and SEM. The oxygen barrier efficiency of the composites was characterized by use of an
oxygen transmission rate (OTR) analyzer. The composites’ properties, such as glass transition temperature (Tg
),
decomposition temperature (Td
), and oxygen barrier, were found to improve. The Tg
s of the composites increased
significantly with the silica content and the 10 wt.% R805 composite exhibited the highest Tg, which was 28.7 °C
higher than that of pure PES (193.8°C). The Td
s of these composites increased from 4.9 °C to 10.6 °C with
silica content ranging from 0.5~10 wt.%. The added SiO2
leads to an increase in Tg
and Td .The oxygen barrier
effectiveness of the composites showed significant improvement when compared to pure PES. The 1 wt.% R974
composite exhibited the lowest OTR, a decrease of 62% when compared to pure PES. These results indicate that
the PES/SiO2 composites have high potential for flexible polymer substrate applications.
