A simple temperature-controlling microwave reaction apparatus was designed by using the domestic microwave oven and was used to study the carboxymethylation reaction of chitosan.It was shown that the temperature of microwave reaction system could be controlled under small and middle microwave power.By using water solvent under microwave instead of isopropanol solvent for the traditional heating method,the carboxymethylation time of chitosan was reduced from 4h to 20min and the degree of substitution of the carboxymethyl chitosan was 0.85.
