Thermochemical and deformational stability of microporous polyethylene films with polyaniline layer

Thermostability and structure transformations upon heating of composite sys tems consisting of a microporous polyethylene film and a conducting polyani line (PANI) layer have been investigated by thermogravimetry (TG), differen tial thermal analysis (DTA), differential scanning calorimetry (DSC), and w ide-angle X-ray scattering (WAXS). Microporous polyethylene films were prep ared by melt extrusion with subsequent annealing, uniaxial extension, and t hermofixation. Polyaniline layers were formed by polymerizing aniline from solution in situ or by deposition of colloidal polyaniline dispersion on th e polyethylene film surface. Composite systems have been found to demonstra te a considerably lower shrinkage upon heating than microporous polyethylen e substrates. It has been discovered from DTA, DSC, and WAXS data that orie nted phases in the polyethylene melt are formed in composite systems at mel ting temperature of polyethylene support. Oriented state in polyethylene me lt is maintained at heating of composite samples up to the temperatures exc eeding polyethylene melting point at several tens degrees. (C) 2001 Elsevie r Science B.V. All rights reserved.