Improving the Properties of Medium Molecular Weight Chitosan/PVA Composite Polymers via Designed ZnO Particles

Abstract

Chitosan exhibit great potential to be a critical part of the global sustainability solution; however, its application areas are limited due to its inadequate properties for some applications. The use of chitosan is limited because of several reasons such as performance (brittleness, poor barrier properties) and processing (low thermal strength temperatures). The properties of chitosan depend on its molecular weight and there are not enough studies in the literature. The application of nanoparticles to chitosan provides new advantages both in improving the properties of chitosan and in reducing its costs. However, such nanoparticles can introduce some difficulties. Nanoparticles additives increase transparency but cause agglomerates due to the high surface/volume ratio, which reduces the local mechanical strength. Recently a novel particle technology, called as MicNo®. MicNo® particles are designed micron size hexagonal plates which are composed of primary fine particles. They only exhibit advantages of micron and nano size. For example, they exhibit superior surface coverage (up to 70% mole) with respect to spherical particles while they are transparent. Accordingly, the research goal of this study was to appraise effects of MicNo® and nano ZnO particles on structure development and hence properties of medium molecular weight Chitosan/PVA films. The results show that MicNo® particles improve UV-resistance and degree of crystallinity of the films and demonstrate great potential as new generation additive systems for biodegradable polymers to extend their application areas.

Keywords

• Chitosan
• Polyvinyl alcohol
• Zinc oxide
• UV-blocking