Chitosan apearance and molecular weight

Pure chitin and chitosan is a white or gray translucent flake or powder solid, tasteless, odorless, non-toxic, pure chitosan slightly pearly luster. Organisms chitin relative molecular mass of 1 × 106 × 106, were extracted chitin relative molecular mass of about 3 × 105 × 105, taken by the chitin system chitosan relative molecular mass of more low, about 2 × 105 ~ 5 × 105. Chitin and chitosan relative molecular mass of the size of the manufacturing process, generally the value of the viscosity level of Goods chitosan depending on the different uses three different viscosity, high viscosity product is 0.7 ~ 1Pa · s in viscosity product is 0.25 ~ 0.65 Pa · s, low viscosity product <0.25 Pa · s. Manufacture of fiber products must be used to the high viscosity of chitin or chitosan.
Chemical properties
Under certain conditions, chitosan can occur hydrolysis, alkylation, acylation, carboxylation, methylation, sulfonation, nitration, halogenation, oxidation, reduction, condensation and complexation chemical reaction, can generate a variety of different properties of chitosan derivatives, thereby expanding the scope of application of chitosan.
Chitosan macromolecule lively hydroxyl food additives and amino groups, which have a strong chemical reaction capability. C-6 hydroxyl can occur under alkaline conditions the following reaction: hydroxyethyl - chitosan with ethylene oxide reaction, available hydroxyethyl derivatives. Carboxymethylation - chitosan with chloroacetic acid reaction will have to carboxymethylation of derivatives. Sulfonic acid esterification - chitin and chitosan and cellulose treated with alkali to generate sulfonic acid ester reaction with carbon disulfide. Cyanoethylated - acrylonitrile and chitosan addition reaction to generate the cyanoethylated derivatives. Chitin and chitosan, the above reaction in the introduction of large side groups, destruction of its crystalline structure, and thus improve the solubility, water-soluble carboxymethyl derivatives show the nature of the polyelectrolyte in solution.