Desenvolvimento e caracterização de filmes compósitos de quitosana e zeólitas com prata

Abstract

Zeolites were subjected to ion exchange or impregnation with silver and added to chitosan films for producing burns dressings. Zeolites were characterized by nuclear magnetic resonance (NMR), total reflection X-ray fluorescence (TXRF), scanning electron microscopy (SEM). The polymer films were analyzed with respect to their mechanical properties, water vapor permeability (WVP), and release of silver. It was observed that the ion exchange did not modify the morphology of the starting zeolite. Clusters of zeolite were observed in the micrographs of the films and they influenced the mechanical properties due to local disruption in the packing of the polymer chains of chitosan. The methodology of ion exchange or impregnation directly influenced the amount of silver present in the zeolite surface and consequently changed the silver release profile in an of simulated exudate fluid. The kinetic models suggested that the release of the silver was not primarily governed by Fick's law of diffusion.