Preparation and characterization of 3,4,5-trimethoxybenzoyl-3,5-dimethylbenzoylchitin

3,4,5-trimethoxybenzoyl-3,5-dimethylbenzoylchitin, a kind of novel macromolecular UV absorbent with good solubility was prepared through the co-acidylating method. The substitution degree of two kinds of acyl group was calculated from the data of elemental analysis. The substitution reaction was demonstrated by the result of FTIR. The crystallinity and thermal stability of the products were studied with the methods of X-ray diffraction and TG. The molar absorptivity values of two kinds of acyl group were 9329.1 L·mol^-1·cm^-1 and 652.7 L·mol^-1·cm^-1 respectively, which were calculated from the data of UV absorbance. Then the acyl group content could be calculated from the UV absorbance data and the results were in agreement with those calculated from the data of elemental analysis.