Carboxymethylation of Chitosan and Its Application in Retan of Leather

摘要

Chitosan is a kind of natural antimicrobial material which widely used in food, medicine, textile, agriculture, and papermaking industry. But it is difficult to be used in leather retanning because of its poor water solubility. In order to improve water-solubility of chitosan, carboxymethylation of chitosan with chloroacetic acid was studied and optimum reaction condition was chosen. The results show that the optimum reaction condition is as follow: the mass ratio of chitosan, NaOH and chloroacetic is:1:7.5:10, the alkalizing time is 3h,the reaction time is 5h, the reaction temperature is 40℃. The modified chitosan is white powder with improved water solubility and antimicrobial ability. The carboxymethyled chitosan was applied in leather retanning and antimicrobial ability of leather was also evaluated. The results illustrate that the modified chitosan has the function to prevent bacteria to breed and the mildew on leather retanned by it is decreased with the increasing of carboxymethyled chitosan used.