Natural chitin which is widely abundant

biodegradable and biocompatible with nontoxicity and low immunogenicity

is a biopolymer with poor solubility in water and common organic solvents

and thus its direct application is rather limited. Nano chitin (chitin nanocrystals or nanowhiskers and chitin nanofibers) isolated from chitin could disperse stably and homogeneously

which not only had the properties of chitin itself

but also had high aspect ratio

high surface area and low density. Moreover

nanochitins had reactive surface (-OH and -NHCOCH

3

and residual -NH

2

groups) that facilitated surface fuctionalization. In this context

the methods isolated nanochitins including hydrochloric acid hydrolysis

2

2

6

6-tetramethylpiperidinooxy(TEMPO) mediated oxidation

dissolution and regeneration process

partial deacetylation

mechanical techniques and electrospinning were reviewed

also the surface modifications of nanochitins and its applications in reinforcement

adsorption and biological activities were summarized.