Relationship between composition and structure in chitosan-based hybrid films

Chitosan/poly (aminopropylsiloxane) hybrid films were obtained by blending 3-(aminopropyl)siloxane oligomers (pAPS) with chitosan (CHI). The pAPS oligomers were prepared by the sol-gel method starting from 3-(aminopropyl)triethoxysilane. These hybrids were characterized by chemical, spectroscopic and morphological methods. Scanning electron micrographs of hybrid films of different composition revealed an organized microscopic pattern suggesting the existence of systematic interactions among their components. Comparison of the thermal stabilities and X-ray diffraction patterns as well as FT-IR spectra of the films with those of the pure components revealed that nanocomposites were formed. Similar studies of films including lithium perchlorate, as a third component, showed that addition of certain amount of lithium ions affected the structure of the CHI/pAPS films. When addition of the lithium salt exceeded the homogeneous incorporation limit, a little excess generated anisotropically oriented patterns in the hybrid films.