PRODUCTION AND CHARACTERIZATION OF BIOPLASTIC FROM WHEAT BRAN STARCH REINFORCED WITH WHEAT STRAW FIBER

Abstract

Nowadays, environmental pollution due to plastic waste taking too long to decay has become a serious problem in the world. Existence without plastics looks like to be difficult because of their important role in society and their applications in virtually all the ranges of daily life. However, there are still a number of drawbacks to plastic, one of which is that it is not easily biodegradable. Therefore, environmentally friendly materials to substitute non-biodegradable materials, such as bioplastics, are urgently needed. Bioplastics made entirely on starch have high water sensitivity, lower mechanical and thermal stability, which can be enhanced by adding cellulosic fillers. In this work, wheat bran starch incorporated with wheat straw cellulosic fiber was used to make bioplastic film. An investigation of proximate analysis of wheat bran and wheat straw was undertaken. The physicochemical characteristics of the prepared starch and fiber samples were examined using analytical techniques. The effect of oven drying temperature (35 - 55 oC), the concentration of glycerol (30 - 40 %) w/v, and concentration of fiber (5 - 15 %) w/w of starch basis was investigated on the tensile strength (TS), elongation at break (EA), and water absorption (WA) of bioplastic film by using Response Surface Methodology (RSM) and physicochemical characteristics of bioplastic film at the optimum point was determined. The obtained results at the optimal point were 20.528 Mpa TS, 8.1 % EA, and 19.44 % WA at a combination of 55 oC oven drying temperature, 31.97 % concentration of glycerol, and 14.40 % concentration of fiber with a high value of (97.1 %) desirability. A statistical model was validated and found to have an insignificant difference between experimental and predicted results. At the optimum point, the value of density (1.54 g/ml), moisture content (16.66 %), water solubility (35 %), transparency (5.6 %) and thickness (0.47 mm) of bioplastic film was determined, and also, the result was analyzed by TGA, XRD, and FTIR. The duration of bioplastic degradation (86.7 %) was produced from the optimum value within 16 days.