Study of the interactions of the nanocomposite formed by poly (vinyl alcohol), clay and zinc oxide nanoparticles

Polyvinyl alcohol (PVAl) is a biodegradable and biocompatible polymer; and due to these characteristics, it is being widely applied in health systems. Zinc oxide (ZnO) nanoparticles have several properties, including antimicrobial activity. Bentonite is a sodium-type clay that has water-absorbing properties, allowing the opening of its coverslips and the entry of other molecules between them. This article studied the interactions of nanocomposites formed by PVAl, bentonite and ZnO nanoparticles, generating nanostructured systems. These systems were produced by solution mixing method at different concentrations. The characterization was made by Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD) and Time-Domain Nuclear Magnetic Resonance (TD-NMR). The results showed that nanocomposites containing both 5 wt% PVAl and 0.5 wt% ZnO of the polymer, and bentonite at concentrations of 3% and 5% by mass of the polymer were randomly organized, being highly amorphous compared to other systems. The clays in these two systems were predominantly exfoliated. These data indicate the synergistic effect between nanoparticles, and a highly random system, containing drug, would retard its diffusion to the outside environment, contributing to a more controlled and lasting release of drugs, enabling their application in pharmacological systems.