Structure and Gas Barrier Properties of Polyimide Containing a Rigid Planar Fluorene Moiety and an Amide Group: Insights from Molecular Simulations.

ABSTRACT: A novel diamine (FAPDA) bearing rigid planar fluorene and amide groups was successfully synthesized. Using such diamine and pyromellitic dianhydride (PMDA), a high-barrier polyimide (FAPPI) was obtained. FAPPI exhibits an outstanding gas barrier. Its water vapor transmission rate (WVTR) and oxygen transmission rate (OTR) are as low as 0.51 g·m^-2·day^-1 and 0.43 cm³·m^-2·day^-1, respectively. Additionally, FAPPI shows excellent thermal stability with a coefficient of thermal expansion (CTE) of 5.8 ppm·K^-1 and a glass transition temperature (T _g) of 416 °C. Molecular simulations, positron annihilation, and X-ray diffraction were utilized to gain insight on the microstructures for the enhanced barrier properties.

SUBMITTER: Liu Y 

PROVIDER: S-EPMC7906589 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature