The effect of degree of deacetylation on the radiation induced degradation of chitosan

Abstract

Radiation-induced degradation of chitosan having different degree of deacetylation (DD) ratios was investigated. Chitosan samples were irradiated with gamma rays in air at ambient temperature in the solid state at a low dose rate. Change in their molecular weights was followed by size exclusion chromatography. Changes in their viscosity values as a function of dose, were also determined. Chains scission yields, G(S), and degradation rates were calculated. It was observed that the DD ratio was an important factor controlling the G(S) and degradation rate of chitosan. The change in the scission yield was attributed to the change in the crytallinity of the chitosan chains that was a result of a change in DD.