Morphological, study on the oriented chitosan film obtained from pre-sheared liquid crystalline solution in dichloroacetic acid

The oriented chitosan films obtained from pre-sheared liquid crystalline ch itosan/dichloroacetic acid (DCA) solutions were studied by means of polariz ed optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The sheer indu ced band texture in the film was found to correspond to the sinusoidal fibr illar microstructure along the shearing direction on the basis of POM and S EM observations. The sinusoidal fibril was found to be lying within the fil m plane. The model of chitosan molecular orientation in the pre-sheared fil m with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shear ing direction. The WAXD azimuthal scanning at 2 theta = 20 degrees indicate s that the (002) plane orients perpendicular to the shearing direction.