Surface deacetylation

Chitosan-sheath and -chitin-core nanowhiskers (CsNWs) have been successfully generated by surface deacetylation of chitin nanowhiskers (CtNWs) in the never-dried state. Acid hydrolysis (3N HCl, 30 mL/g, 104 ◦C) of pure chitin derived from crab shell yielded 65% 4–10 nm thick, 16 nm wide and 214 nm long chitin whiskers (CtNWs) that were 86% crystalline and 81% acetylated.

9p vihermione 06-01-2023 16 2   Download

Procedures for chitin nanofiber or nanocrystal extraction from Crustaceans modify the chitin structure significantly, through surface deacetylation, surface oxidation and/or molar mass degradation. Here, very mild conditions were used to disintegrate chitin fibril bundles and isolate low protein content individualized chitin nanofibers, and prepare nanostructured high-strength chitin membranes.

9p vihermione 06-01-2023 8 2   Download

Physical adsorption has shown to be facile and highly effective to deposit chitosan nanowhiskers (CsNWs, 60 % deacetylated, length: 247 nm, thickness: 4–12 nm, width:15 nm) on electrospun cellulose acetate nanofibers (CANFs, 560 nm) to effect complete surface charge reversal from negatively charged CANFs (− 40 mV) to positively charged CsNWs-adsorbed CANFs (+8 mV).

9p viginny 30-12-2022 8 3   Download

The present work focused on the synthesis of b-chitosan submicron particles (CSPs) from Todarodes pacificus using mechanochemical techniques. The gladius was submitted to a sequence of mechanical and chemical treatments to synthesize b-chitin (CT), which was further deacetylated to form spherical chitosan submicron particles with an average diameter of 6100 nm. The surface morphology of b-chitin and CSPs was observed using electron microscopy. The degree of deacetylation (DD%), evaluated from the absorbance peak of a Fourier Transform Infrared (FTIR) spectrum, was 80 ± 2.5%.

9p kequaidan1 16-11-2019 22 0   Download