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In this paper, a new method of chitosan degradation was put forward first time: Electrochemical process. In addition, two degradation methods of electrochemical and Sonoelectrochemistry were compared.The degradation effect of current density, temperature, initial concentration, pH and other factors were investigated.The structure of chitosan and its degradation products were identified by FT-IR, XRD, UV, TG. The results are showed as follows:(1) Chitosan was degraded by electrochemical, The results showed that the Ti/SnO2-Sb2O3 electrode was better than Ti/TiO2-RuO2 electrode on chitosan degradation, a magnetic stirring effect is better than no magnetic stirring, Degradation effect increased with the current density, system temperature and molecular weight of material, decreased with the initial concentration of chitosan, while exhibited an increase-to-decrease trend with the pH. In addition, the reaction kinetics of electrochemical degradation was researched. The relative curves of ln[Nn/(Nn-1)] versus reaction time in degradation process showed linearity, and the reaction kinetics is first order.(2) Chitosan was degraded by Sonoelectrochemistry, found that the degradation effect of chitosan by Sonoelectrochemistry is better than electrochemical or ultrasonic. Degradation effect increased with the current density, system temperature and molecular weight of material, decreased with the initial concentration of chitosan, while exhibited an increase-to-decrease trend with the pH.(3) The experimenial results showed that water-solubility chitosan can be effectively produced by two degradation methods. By the characterization tests, the degradation of chitosan by electrochemical and Sonoelectrochemistry did not destroy basic functional group, structural unit and the crystallization degree of chitosan. In degradation process, the main fragmentation occurred in theβ-(1,4) glycosidic bond.
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