Influência da granulometria da casca de arroz nas propriedades físicas e de biodegradação de biocompósitos de matriz de farelo de arroz.

Abstract

The growing environmental concern for the rational use of natural resources drove the development of new materials. Biocomposites reinforced with natural fibers have been highlighted in research due to their enormous potential to replace synthetic materials in certain applications, together with the environmental gains offered. Thus, this work presents an innovative material in the construction of biocomposites produced from agro-industrial by-products, constituted by the matrix of raw rice bran (70% of the composition), reinforced with rice husk fibers (15% of the composition) of different sizes particle (> 1mm,> 500 μm,> 250 μm and <250 μm) and glycerol (15% of the composition) as a plasticizer, in addition to a sample produced only with rice bran (100% of the composition). The materials were mixed manually and then molded by thermal compression in a tray format at 140 ° C and pressure of 4 tons with a total cycle time of 5 minutes. These molded parts were subjected to tests of biodegradability, contact angle, water absorption and impact resistance. Results of this study showed the influence of the incorporation of the rice husk fiber in the improvement of the evaluated properties when compared to the biocomposite produced only with rice bran. The different grain sizes of the rice husk fiber used in this study had little influence on the properties evaluated, however it should be noted that biocomposites with a grain size> 250 μm and <500 μm (70% of the composition) showed significant improvements, such as: greater impact performance , greater angle of initial contact and less loss of mass in composting in the evaluated period. Finally, the study demonstrates the potential of using rice bran as a matrix in biocomposites, however more research is needed so that the material can be improved and be able to replace synthetic materials according to its purposes.