Chitosan is a natural polymer which is the only cationic alkaline polysaccharide that found so far. It contains reactive functional groups

such as hydroxy and amino. It has excellent properties

such as biocompatibility

microbial degradation

antibacterium

and no cytotoxicity. And it has promising appilcations in many fields

such as biochemistry

medicine

environmental protection and agriculture. However

due to better stereoregularity and stronger hydrogen bonding

chitosan is insoluble in water and other organic solvents except dilute hydrochloric acid and dilute acetic acid

which limits its application scope. In order to expand its application field

the graft copolymerization reaction is usually used to improve the performance of chitosan. In this paper

the latest researches about chitosan graft copolymerization

including free radical initiated grafting

coupling grafting

catalysis grafting are introduced.