Surface engineering of cellulose nanocrystals via SI-AGET ATRP of glycidyl methacrylate and ring-opening reaction for fabricating self-healing nanocomposite hydrogels

In this manuscript, self-healing nanocomposite hydrogels were successfully fabricated with nanocomposite materials based on functional cellulose nanocrystals (CNCs). CNCs were firstly extracted from microcrystalline cellulose by a typical and eco-friendly method with choline chloride and oxalic acid dihydrate as deep eutectic solvents. Well-defined poly(glycidyl methacrylate) (PGMA) was further grafted on the surface of CNCs by surface-initiated activator generated by electron transfer atom transfer radical polymerization. After ring-opening reaction of PGMA, CNCs@PGMA-OL nanocomposites with diol functional group were successfully obtained and further implanted into poly(acrylic acid)/guar gum-based self-healing hydrogels by multiple reversible weak interactions. These nanocomposite hydrogels display outstanding self-healing and mechanical strength properties, providing a facile strategy for the design and development CNC-based functional materials.