Abstract Chitosan is a derivative of chitin, a natural polymer present in the exoskeleton of crustaceans such as crabs and lobsters. This polymer is characterized by its high biodegradability, biocompatibility and mucoadhesivity, which is a raw material of interest for the pharmaceutical and food industry. However, its applications are limited by the insolubility at pH greater than 6. One of the most important derivatives of chitosan is N, N, N-trimethyl chitosan hydrochloride, a polymer obtained by a quaternization process of the amino groups present in chitosan. The objective of this work was to evaluate the influence of stirring rate and reaction time on the chitosan trimethylation process. A methylation process of the chitosan was performed, using as alkylating agent dimethyl sulfate and absolute ethanol as the precipitating agent. The influence of the speed of agitation and reaction time on this process was studied. It was found that the stirring rate influences the process. In conclusion, the results obtained in this work showed that with the use of dimethyl sulfate as an alkylating agent, applying a stirring speed of 300 rpm and a time of 2 h, it is possible to transform chitosan in N, N, N trimethylchitosan chloride.
Keywords Chitosan,N,N,N-trimethylchitosan hydrochloride, Degree of quaternization, Stirring rate, Reaction time.