Compósitos produzidos com resina poliéster e fibras de eucalipto tratadas termicamente

Abstract

Solutions that lead to the production of new and more sustainable materials, with innovative traits, have motivated the scientific community to seek alternatives to substitute raw materials obtained from non-renewable sources. In this scenery, the composite materials produced with plant fibers are highlighted given its reduced cost, high availability, good mechanic resistance, low density and renewable origin. In this sense, the objective of this work was to analyze the influence of the insertion of different contents of eucalyptus fibers, as well as its therm al treatment, over the physical-mechanic properties of polymeric composites. The resin used was the orthophthalic unsaturated polyester, using methyl-ethyl-cetone peroxide as curing catalyst. The fibers were used in the concentration of 0, 5, 10, 15, 20, 25 and 30% m/m. After defining the best concentration, the effect of the thermal treatment were evaluated at the temperatures of 140, 170, 200 and 230 o C. The composites were evaluated regarding its mechanical (traction, flexion and impact), physical (density and water absorption) and microstructural properties. The content of 25% of reinforcement was the most adequate for composite production. The thermal treatment applied to the fibers caused significant changes in its chemical and anatomical compositions, which resulted in changes in the physical and mechanical properties of the composites. The temperature of 230 o C was the most indicated for treating the fibers during the production of the polymeric composites with unsaturated polyester matrix, allowing the decrease in the density and water absorption, as well as improvements in the traction properties of the composites. There was no effect of this treatment over the rupture model over static flexion and impact, however, a reduction of the elasticity model over static flexion was observed.