Chitosan-functionalized silica nanoparticles as a multifunctional coating material for improved water repellency, antimicrobial activity and mechanical strength of degradable bioplastics

Abstract

Degradable bioplastics have become a promising solution to plastic pollution. One of the major challenges facing more widespread usage of bioplastics is the premature structural disintegration, especially at the surface, mainly due to their inherent mechanical weakness and continuous hydrolysis. To overcome these limitations, this study herein presents a simple, yet highly effective strategy of surface coating chitosan-functionalized silica nanoparticles (SNP) for bioplastics. SNP itself has been widely shown to be an effective hydrophobic coating material, but introducing chitosan on SNP not only further increased the hydrophobicity, but similarly enhanced the mechanical strength of the bioplastics through increased physical interaction with cationic chitosan. Furthermore, the natural anti-microbial activity of chitosan could be imparted to the coated surface. As a whole, the chitosan-functionalized SNP is highly advantageous as a multifunctional coating material.