Preparation and charactarization of gluten based biodegradable blends

In recent years, the research topics about using renewable and natural resources, instead of synthetic and petroleum-based materials, have gained a considerable popularity. As a country with large scale agricultural production, each year Turkey produces big quantities of agricultural waste, which can be used as renewable raw materials for manufacturing variety of products with added value. Use of agricultural waste to produce biodegradable products creates an economic value for this otherwise worthless agricultural waste, as well as generating an alternative, more cost effective disposal process. Gluten is a protein based side product of wheat starch production process. The prominent features of gluten are its high molecular weight, common apolar character, and the variety of its fractions. Gluten based films can be used in many applications due to their high water resistance, homogeneity, transparency, and mechanical strength properties. In this paper, a blend of low density polyethylene, a petroleum-based polymer, and gluten, a natural polymer, has been prepared by extrusion method. The current extruder has twin screw and l/d ratio is 24. Then, with the same extruder, films from the blend have been produced. The mechanical properties of these films have been determined by tensile tests; thermal properties have been determined by differential scanning calorimetry and thermal gravimetric analysis; and morphologic properties have been determined by a scanning electron microscope. Also, biodegradability has been specified by water absorption and fungi resistance tests. The resistance of microorganism of the films have been identified in the existence of Aspergillus Niger, a bread mould.