Preparationof

Chitosan

Purified Chitin

55 % NaOH Solution

Water bath at 95 °C for 4 hours

Chitosan

Preparation of Chitosan

Chitosan Preparation

Chitosan Preparation

Chitosan Preparation

ChitinAdding 50% NaOH

Boiled at 100°C for 2 hours

Washed continuously with the 50% NaOH and filtered

Chitosan

Deacetylation

Chitosan nanofibers were also produced by the electrospinning of chitin solutions using 1,1,1,3,3,3- hexafluoro-2-propanol (HFIP) as the spinning solvent.

Fiber diameters ranged between 50 and 460 nm, but most fibers were smaller than 200 nm.

Electrospinning

Preparation of Chitosan

i. The chitin (10g) was put into 50% NaOH at 60°C for 8h to prepare crude chitosan.

ii. After filtration, the residue was washed with hot distilled water at 60°C for three times.

iii. The crude chitosan (4.1g) was obtained by drying in an air oven at 50°C overnight.

Preparation of Chitosan

I. Chitin is treated with 30 ml of 40% sodium hydroxide solution at 105 C for 60, 90 and 120 min, respectively.

II.After filtration, washing to neutral with deionized water and freeze drying, the corresponding chitosan obtained

Nanowhisker a type of filamentary crystal (whisker) with

cross sectional diameter ranging from 1 to 100 nm and length

to diameter ratio >100.

Nanowhisker

Needle or short rod-like structure

Average length of 250 nm

It can be several dozen times stronger

than regular crystals and can

demonstrate considerable flexibility

and corrosion resistance.

Chitin nanocrystals are prepared from chitin powder by using acid hydrolysis with sulfuric acid and phosphoric acid.

The prepared nanocrystals were characterized and compared with nanocrystals prepared by conventional HCl hydrolysis.

Nanocrystal