Preparação e caracterização de filmes de eletrólitos sólidos poliméricos a partir de PAN/PVA pela técnica de inversão de fases

Abstract

This work involved the preparation and thermal characterization a polymeric solid electrolyte obtained by phase inversion technique in a non-solvent from the copolymer polyacrylonitrile (PAN) and polyvinyl vinyl (PVA) in ethylene carbonate / carbonate dimethylene (EC / DMC 1:1 V / V) with different concentrations of LiClO4. The films were self-sustaining, thin, porous and with good prospects for use as ESP\'s in lithium ion batteries. The X-ray diffractograms of ESP\'s behavior showed predominantly amorphous of thin films, since the Micrographs revealed micrometer-scale pores (mesopores) distributed in the polymer chain and partial dissociation of the lithium salt. The thermograms showed greater thermal stability when compared to the films gels and thermal stability of the film without lithium salt indicating that the addition of the lithium salt contributes to the degradation of the polymer matrix, besides verify a low glass transition temperature (of 67 to 57 ºC). By infrared spectroscopy (IR), one verified that the various additions of lithium salt caused significant changes in the structure of the polymer chain, being possible to observe bands among other, interactions bands between lithium ions and the polymer matrix. The maximum ionic conductivity of ESP\'s immersion in acetone and methanol, at room temperature, was 4.85 x 10-11 S cm-1. 1.47 x 10-7 S cm-1, respectively.