SYNTHESIS OF HIGHLY SUBSTITUTED BUTYRYL CHITIN IN THE PRESENCE OF PERCHLORIC-ACID

Perchloric acid was used as a catalyst for butyrylation of krill chiti n. Esterification was carried out under heterogeneous conditions using a large excess of butyric anhydride at 20 degrees C and 40 degrees C. The effect of catalyst concentration and duration of the reaction on molecular weight and yield of butyryl chitin was investigated. Butyryl chitin with a degree of substitution of 2 in 90% yield were obtained. These butyryl chitins were soluble in various organic solvents and fo rmed strong transparent films and fibers. The butyryl chitin also show s good resistance to gamma irradiation.