Preparation and physical properties of konjac glucomannan-polyacrylamide blend films

The blend films of konjac glucomannan (KGM) and polyacrylamide (PAAm) were prepared by using the solvent-casting technique. Transparent blend films we re obtained in all blending ratios. The physical properties of the films we re investigated by Fourier transform infrared spectroscopy, wide-angle X-ra y diffraction, thermogravimetric analysis, scanning electron microscopy, an d by measurement of mechanical propel ties. The results indicated the occur rence of intra- and intermolecular interactions of the pure components, as well as the intermolecular interactions between KGM and PAAm through hydrog en bond formation. The thermal stability and mechanical properties of both tensile strength and elongation at break of the films were improved by blen ding KGM with PAAm. It was worth noting that the blend film had the greates t tensile strength when the KGM content in the blend films was around 30 wt %. Surface morphology of the films observed by SEM was consistent with the above-noted results. Furthermore, the water absorbability of the blend fil ms was also investigated. (C) 2001 John Wiley & Sons, Inc.