Study of thin films made from poly (amide-imide)s containing nitrile groups

Abstract

Flexible thin films based on poly (amide-imide)s were obtained by casting technique and their properties were studied. The polymers were synthesized by solution polycondensation reaction of trimellitic anhydride chloride with 2,6-bis (m-aminophenoxy)-benzonitrile or 2,6-bis (p-aminophenoxy) benzonitrile. They were easily soluble in polar amidic solvents such as N-methyl-2-pyrrolidone and showed high thermal stability, with decomposition temperature being above 400°C. Composite films based on these polymers and pyrite ash powder were also prepared. An interferometric method was used for measurement of the linear displacement of polymeric composite membranes by applying an electrical tension.