Experiment and Molecular Dynamics Simulation Studies of 3,3′,4,4′‐Biphenyltetracarboxylic Dianhydride‐Based Transparent Polyimide Films Containing Ether and Sulfone Linkages in the Diamine Monomer

ABSTRACT In this study, we report experimental observations and molecular dynamics (MD) simulation results for two transparent polyimide (PI) systems that use 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA) as the dianhydride monomer and bis[4‐(4‐aminophenoxy)phenyl] sulfone (p‐BAPS) and bis[4‐(3‐aminophenoxy)phenyl] sulfone (m‐BAPS), which contain both ether (O) and sulfone (SO 2 ) groups, as the diamine monomers. FT‐IR structural analysis clearly shows that the PI films used in this study were successfully synthesized and fabricated. In addition, the DSC and TGA analysis results clearly indicate that the PI film based on BPDA/p‐BAPS has a higher T g and greater thermal stability than the PI film based on BPDA/m‐BAPS, which appears to be due to the structural differences in the benzene ring substitution of the diamine monomers on p‐BAPS and m‐BAPS. Additionally, the two PI films fabricated in this study exhibited relatively high transmittance, ranging from 85% to 87% at 500 nm. Finally, although small‐scale MD simulations were performed in this study, it was nonetheless confirmed that the overall motion of PI molecules and gases within the amorphous PI cell can be influenced by the structural characteristics of diamine monomers such as p‐BAPS and m‐BAPS.