2012 Volume 69 Issue 8 Pages 460-467
Chitin nanofibers are prepared from the exoskeletons of crabs and prawns by a simple mechanical treatment. The obtained nanofibers have fine nanofiber networks with a uniform width of approximately 10–20 nm and a high aspect ratio. Chitin nanofibers are acetylated to modify their surfaces. The acetyl DS can be controlled from 1 to 3 by changing the reaction time. Optically transparent chitin nanofiber composites are prepared with acrylic resins. Due to the nano-size structure, all of the composites are highly transparent. Chitin nanofibers significantly increase the Young’s moduli and the tensile strengths and decrease the thermal expansion of all acrylic resins due to the reinforcement effect of chitin nanofibers. Chitin nanofiber shows chiral separation ability. The chitin nanofiber membrane transports the D-isomer of glutamic acid, phenylalanine, and lysine from the corresponding racemic amino acid mixtures faster than the corresponding L-isomer. The chitin nanofibers improve clinical symptoms and suppress ulcerative colitis in a DSS-induced mouse model of acute ulcerative colitis.
