Degradation behavior of natural fiber reinforced polymer matrix composites

Nowadays, polyethylene (PE) and polypropylene (PP) based plastic materials are being extensively used for commercial and household purposes. However, these polymer based plastics are substantially resistant to biodegradation. Thus their increasing accumulation in the environment is proving to be an ecological threat to the world. Consequently, over the last couple of decades exhaustive studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. In this research, the improvement in the biodegradability of PP was observed by blending it with small additions (5%) of wood sawdust and wheat flour. The developed composites were then exposed to various environmental conditions namely: exposure to the open atmosphere, moist soil, water and brine solution for a period of 15 weeks. After exposure, the composites were visually inspected to find signs of crazing and discoloration that indicated the onset of biodegradation. The extent of the biodegradability of the composites was also observed by change in bonding nature by FTIR spectroscopy. In addition, the change in tensile properties of the composites after exposure was measured by tensile tests. The experimental results revealed that addition of both sawdust and wheat flour considerably improved the biodegradability of PP. The most pronounced biodegradation was exhibited by samples exposed to brine solution and those buried under moist soil. (C) 2013 The Authors. Published by Elsevier Ltd.