PREPARATION AND PROPERTIES OF CHITOSAN HYBRID FILMS FROM MICROWAVE IRRADIATED SOLUTIONS

The effect of microwave irradiation (MW, 1.55 kW at 2450 MHz on the dissolution chitosan(CHI) and on the properties of the solutions was studied and the results compared with those obtained by using mechanical stirring. MW effects were tested by analysing the viscosity of the solutions as well as the properties of the films of the nanocomposite the chitosan with poly(3-(aminopropyl)triethoxysilane)(pAPS) they produce. Microwave irradiation induces rapid dissolution, leading to solutions with relatively low viscosity, which asymptotically increases with further irradiation. Dissolution-precipitation-redissolution experiments with samples prepared using both methods indicate that MW effects are more related with the aggregation state of the macromolecule in the solution than with the chitosan degradation. CHI/pAPS hybrid materials appear to be different when the solutions of chitosan used as precursor are obtained by MW irradiation. Thus, MW appears to affect the chitosan self-association so changing the equilibria between the micro domains involved in the macromolecular complex formation.