Optimum Preparation Conditions for Highly Individualized Chitin Nanofibers Using Ultrasonic Generator

alpha-Chitin derived from crab shells was treated with 30% sodium hydroxide to prepare partially deacetylated chitin with a deacetylation degree of 36%. Partially deacetylated chitin nanofibers were prepared by applying weak ultrasonic energy generated by a domestic ultrasonic cleaner. The deacetylated chitin was easily disintegrated into nanofibers with the aid of electrostatic repulsion and osmotic pressure effect of amino cations on the chitin surfaces. The nanofibers were characterized in terms of yield, morphology, crystallinity, viscosity, and dispersibility. After a series of characterizations, ultrasonication with 45 kHz frequency and 20 min treatment was found to be the optimum conditions for obtaining fine nanofibers with a high yield.

Automated summary

The alpha-chitin derived from crab shells was partially deacetylated with 30% sodium hydroxide to obtain a deacetylation degree of 36%. Partially deacetylated chitin nanofibers were successfully prepared using weak ultrasonic energy from a domestic ultrasonic cleaner. The optimal conditions for obtaining fine nanofibers with high yield were found to be ultrasonication at 45 kHz frequency for 20 minutes.