Elaboração de compósitos poliméricos de EcobrasTM com fibra da casca de coco verde e avaliação de sua biodegradação

Abstract

The discharge of polymeric materials is one of the main causes of environmental pollution, thus stimulating research and development in the field of biodegradable materials, such as polymeric composites. A commercial biodegradable polymer named EcobrasTM, constituted of polyester and corn starch is being considered a good alternative in this case, particularly due to its production from renewable sources. The green coconut husk is a low cost lignocellulosic material, due to its large scale generation as residue. The present Thesis deals with the preparation of a new EcobrasTM composite with green coconut husk, the study of its biodegradation in simulated soil and the evaluation of the influence of the microbial consortium found in the soil during the process of biodegradation of these materials. The test of biodegradation performed in the simulated soil consists in the introduction of the samples in the soil, under different periods of time, according to ASTM G 160-03 regulation. After each interval, samples were removed from the soil and observed by Optical and Electron Scanning microscopies, Scanning Differential Calorimetry, Thermogravimetric analysis and Infrared Spectroscopy. The confirmation of the presence of microorganisms in the soil during biodegradation occurred through the study of the partial and total substitution of the energy source from the Sabouraud and Plate Count Agar media. It could be observed that the EcobrasTM matrix and the natural fibers are both biodegradable. Besides, after the biodegradation test in simulated soil, the presence of microorganisms was confirmed and visualized on the surface of the material by Scanning Electron Microscopy