Synthesis of functional polyimide and its application in nanostructured films

Abstract

A functional polyimide with pendant carboxylic groups has been synthesized and modified with dendrimer wedges. The effect of dendrimer wedges in formation of porous structure in bulk film was investigated. Lower density and higher extend of butanol intrusion of the modified polyimide bulk film after thermal treatment shows uniform porous structure. Langmuir-Blodgett films were fabricated with the as-synthesized polyimide and the modified polyimide. The carboxylic polyimide Langmuir-Blodgett film can be obtained after thermal treatment at lower temperature than typical imidization temperature. Less dense Langmuir-Blodgett films can be fabricated with modified polyimide followed by thermal treatment. Silver nanoparticles/ polyimide composite Langmuir-Blodgett films were fabricated successfully using immersion method and subphase method. Layer-by-layer self-assembled films were fabricated with the carboxylic polyimide and modified polyimide. The covalent bonds formed in carboxylic polyimide layer-by-layer film improved the resistance against the solvents and high temperature. The steric effect of modified polyimide results in loose layer-by-layer films.