The properties and preparation of crosslinked chitosan films

The crosslinked chitosan films were prepared with epichlorohydrin as a crosslinking agent, and characterized by FTIR, X-ray diffraction and SEM. Their mechanical properties were measured. The structure analysis indicated that at low temperature, the crosslinking reaction only occurred between -NH2 group of chitosan and epichlorohydrin. When the temperature was above 40 degrees C, -OH group of chitosan reacted with epichlorohydrin. The results from SEM and measurement of mechanical properties showed that the tensile strength of the crosslinked films was considerably improved, and the rate of degradation of crosslinked films by lysozyme was reduced. The new crosslinked chitosan films are expected to be used as controllable degradation biomaterials.