Multifunctional Chitosan Nanocomposites: the Effect of Silver Supported on Montmorillonite Platelets on Barrier and Mechanical Properties

Multifunctional bionanocomposites have been prepared by loading chitosan matrix with silver-montmorillonite antimicrobial nanoparticles obtained by replacing Na+ ions of natural montmorillonite with silver ions followed by thermal reduction to metallic nanoparticles. This filler has been chosen for its twofold advantage to serve as silver supporting material and to confer new and better performance to the obtained material. It has been proved that the ultrasound-assisted procedure resulted in an efficient tool for the chitosan macromolecules to intercalate into the silicate galleries. The achievement of the intercalation as well as the interaction between chitosan and silver nanoparticles lead to an enhancement of barrier properties of the bionanocomposites and to an improvement of their mechanical strengths mainly due to a better load transfer between matrix and fillers.