INFLUENCE OF THE CHEMICAL TREATMENT OF CURAUÁ (ANANAS ERECTIFOLIUS) VEGETAL FIBERS ON THE MECHANICAL RESISTANCE OF COMPOSITES IN EPOXY RESIN MATRIX

The use of vegetable fibers as reinforcing agents in polymer composites is being increased in substitution of synthetic fibers such as glass fibers or carbon fibers because of good mechanical properties and low density among other properties. In this work an evaluation of epoxy resin composites and curauá fibers is carried out, whose fiber is extracted from the leaves of a plant from the Amazon region called Curauá (Ananaserectifolius). The objective of this work was to study the interaction between the curauá fiber and the resin aiming at a greater bonding of the fiber in the matrix and with that increase the mechanical properties of the composite. Treatments to improve the fiber's wettability were based on sodium hydroxide by varying the concentration and the exposure time of the fibers in the dissolutions. After treated fibers were observed in the Scanning Electron Microscope (SEM) to compare the results of the treatments in relation to the fibril separation and the surface roughness of the fibers, the results of which were then compared with the results of the tensile test. In order to carry out the work, was constructed a mold composed of several male and female cavities with standard dimensions according to the norms for mechanical tensile tests of composites in polymer matrix and fine parallel longitudinal and transversal slits were machined to place the fibers with precision. As a result of the work the 5% sodium hydroxide dissolution which 4 hours of exposure was determined as the best treatment, whose tensile strength values were high, stating that this fiber could in the future replace the glass fiber.