Grafting Well-Defined Synthetic Polymers to Chitosan Nanocrystals via Nitroxide-Mediated Polymerization

Abstract

Chitosan nanocrystals (ChsNCs) are a renewable resource attracting research interest due to their outstanding physical, chemical, and mechanical properties. ChsNCs exhibit promising potential applications as reinforcing materials in polymer-based nanocomposites. However, the hydrophilic surface of ChsNCs leads to poor dispersibility in hydrophobic polymer matrices, hindering these potential applications. In this work, the first graft modification of ChsNCs using nitroxide-mediated polymerization (NMP) is reported. ChsNCs are initially functionalized with glycidyl methacrylate to provide a reactive surface group that enables the polymer-graft modification. Polystyrene and poly (methyl methacrylate) with well-defined molecular weight polymers are first synthesized via NMP, and the polymers are then “grafted to” the ChsNCs surface, yielding polymer-graft modified ChsNCs.