Highly efficient grafting of polyvinyl acetate onto cellulose nanocrystals in the aqueous phase

Abstract

Although grafting polymers on cellulose nanocrystals (CNCs) has attracted extensive attention due to their vast application prospects, the current grafting materials are mainly petroleum based polymers, which are unsustainable. Herein, by adding a trace amount of sodium citrate, a highly efficient grafting of bio-derived polyvinyl acetate (PVAc) onto the surface of CNCs was realized through classical free radical polymerization initiated by cerium ammonium nitrate (CAN) in an aqueous medium. The grafting yields of PVAc on the CNC surface climbed from 29.2% to 241.9% when the SC concentration was increased from 0 to 0.45 mmol L⁻¹. The thus obtained CNC–PVAc can be almost completely degraded by soil burial for about 180 days, and therefore can be used as a new biodegradable nanofiller or polymer nanocomposite. Moreover, this strategy is generally applicable to various monomers and different surface groups of CNCs.