Well-Defined Glycopolymer Chitosan Mimics for Design of Chitosan Nanocomposites

Chitosan, a naturally derived polysaccharide with intriguing antimicrobial and polycationic properties, is highly desirable as a biosourced and biodegradable material for biomedical, food packaging, and personal care applications. Its inherent high levels of variability in molecular weight, dispersity, and degree of deacetylation, however, make the establishment of structure-property-processing relationships difficult and limit materials development. In this study, a novel methacrylate-based glycomonomer with saccharide structure similar to that of chitosan was synthesized and copolymerized with methyl methacrylate via reversible addition-fragmentation chain-transfer (RAFT) polymerization to create a series of well-defined chitosan mimics with controlled molecular weights and low dispersity (<1.1). Evaluation of mammalian cytotoxicity and antibacterial activity against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> revealed performance similar to that of chitosan. The copolymers were used as models to evaluate difficult-to-probe interactions between chitosan and graphene oxide (GO) and elucidate mechanisms of mechanical property improvements observed in chitosan/GO nanocomposite films.