The preparation and applications of functional fibres from crab shell chitin

Novel chitin–silk fibroin fibres and chitin fibres were prepared by an environmental friendly wet-spinning method. Each aqueous solution of sodium chitin ( N-acetylchitosan) salt and its blends of silk fibroin in aqueous 14% sodium hydroxide was spun through a viscose-type spinneret into an aqueous 10% sulfuric acid solution saturated with ammonium sulfate (about 43%), and the corresponding white filament was obtained. The tenacity and elongation values of the chitin–silk fibroin filament decreased with an increase of fibroin content up to 33% by weight. A scanning electron microscopy analysis revealed that both the chitin filament and the chitin–silk fibroin (67:33, w/w) filament had vertical strips with faint scale structures on their surfaces. Some applications of these staple fibres were also reported.