Production of thermoplastic starch/MMT-Sorbitol nanocomposites by dual-melt extrusion processing

A green processing method, dual-melt exturtion, was used to prepare thermoplastic starch/montmorillonote nanocomposites without organic reactions in the solution. XRD demonstrates that sorbitol enlarged the interlayer distance of MMT during the first step. MMT-sorbitol, formamide and starch were used to obtain TPS/MMT nanacomposites in the second step. XRD and TEM reveal that TPS intercalated the layers of MMT. With increasing MMT content, improvements in thermal stability, tensile strengh, Young's modulus and energy break, and a slight decrease of elongation at break, appeared. The effect of water content on the tensile strenght and elongitation at break was also studied.