chitosan

Chitosan is a natural biopolymer derived from chitin (found in crustacean shells and fungal cell walls), typically produced by deacetylation of chitin. It is a cationic polysaccharide with tunable properties depending on degree of deacetylation and molecular weight, making it attractive for applications requiring biodegradability and biocompatibility alongside moderate mechanical strength. The material is widely used in biomedical devices, water treatment, food processing, and cosmetics due to its antimicrobial properties, ability to form films and fibers, and compatibility with biological systems; compared to synthetic polymers, chitosan offers environmental sustainability and reduced toxicity, though it requires careful moisture management and has lower thermal stability than many conventional engineering plastics.