Facile preparation of nanochitins via acid assisted colloid milling in glycerol

A facile route was developed for the production of nanochitins. Acid-assisted glycerol swelling at 120 °C and low-intensity colloid milling were found to be sufficient for the successful nanofibrillation of purified chitin. The glycerol together with a small amount of sulfuric acid was employed to break the hydrogen bonds between the chitin fibrils, and then the excessively swelled chitin bundles were easily disassembled to the nanoscale through mechanical disintegrations. Despite their good dispersibility in glycerol, the prepared nanochitins were also well-dispersed in acidic and neutral aqueous solutions. Optimal reaction conditions such as the amount of sulfuric acid and processing time for colloid milling were determined to be 0.64% w/w sulfuric acid (based on the whole reaction system) and 2 h, respectively. Under the optimal conditions, nanochitins with a fibril width of less than 50 nm and length of several microns were obtained with high yield (approximately 85%).