Characterization of konjac glucomannan-gelatin blend films

Novel blend films of konjac glucomannan (KGM) with gelatin were prepared by using the solvent-casting technique. Transparent blend films were obtained in all blending ratios of the two polymers. The structure and physical pro perties of the films were investigated by Fourier transform IR, wide angle X-ray diffraction, thermogravimetric analysis, differential thermal analysi s, scanning electron microscopy (SEM), and strength tests. The results indi cated that intermolecular interactions between the KGM and gelatin occurred that were caused by hydrogen bonding and the physical properties of the fi lms largely depended on the blending ratio. The crystallinities of the blen d films decreased with the increase of the KGM. The thermal stability and m echanical properties (tensile strength and elongation at break) of the film s were improved by blending KGM with gelatin. It is worth noting that the b lend films had a good tensile strength of 38 MPa when the KGM content in th e blend films was around 30 wt %. The surface morphology of the blend films observed by SEM displayed a certain level of miscibility. Furthermore, the water absorbability of the blend films was also measured and discussed. (C ) 2000 John Wiley & Sons, Inc.