It was studied the feasibility of using corn cob to obtain a polymer composite. It was used of the corn cob in Three-grain sizes, and some formulations of the composite of polyester resin and powders were used, and the most appropriate formulation was chosen. For the characterization of the composite thermal and mechanical properties were determined. The main advantage of the composite was the low density, about 1.06 kg/m³ for the thick powder formulation. The composite presented an inferior mechanical behavior concerning the resin for all the studied particle sizes and formulations. The composite presented better mechanicals results for the bending strength, reaching 25.3 MPa for the thick powder formulation. The composite also proved itself to be viable for thermal applications since it has average thermal conductivity inferior to 0.21 W/m, being classified as thermal insulation and can be used to manufacture structures that do not require significant mechanical strength, such as tables, chairs, benches, panels, works of art, crafts and solar prototypes, such as ovens and stoves.

The objective of this research was to obtain composites using petioles bamboo and ophthalmic lens waste powders and polyester resin. Such materials have no defined application, they are produced in large quantities and their waste is discarded irregularly in landfills. Bamboo and ophthalmic lens rejects powders were produced, with particle sizes of 2.07 mm and 1.14 mm, respectively. Preliminary tests were carried out to determine the maximum quantities of each material to be mixed with the polyester resin matrix, in order to guarantee the good processability of the new material produced. The mass quantities used were 10 and 15% bamboo, 15 and 40% tailings and a hybrid composition with 5% bamboo and 20% tailings, to obtain the desired composites. The composite plates were manufactured by the cold compression wet molding process in closed mold. Several tests were carried out to characterize the composites that were produced. It was found a decrease in the mechanical strength of the composite in comparison to the matrix, concluding that the bamboo powders and ophthalmic lens waste had a filling load function in the composites produced. The most expressive result of the composites was in the impact resistance, corresponding to 0.55 J/cm2 for OLWP 40% higher in 39.6% in relation to the polyester resin matrix. As a practical application, table and bench tops were manufactured with the most economically and ecologically viable composite, 40% OLWP.

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The carnauba, the tree of life, is a palm tree found in all regions of Brazil and has many applications, from electronics to cosmetics, with a greater emphasis on wax. The objective of this research was to obtain composites using petioles fibers from carnauba leaves and polyester resin. The powder was obtained using forage grinding and subsequent sieving, generating residues with different grain sizes. All the obtained granulometries were tested and the smaller one was chosen, due to its greater viability to obtain the composite, due to its better processability. Three mass proportions of the mixture between matrix and residues were chosen, 5%, 7.5% and 10%, since above that percentage there was a compromise in the processability and obtaining the composite studied. Mechanical, thermal and environmental characterizations were performed, which demonstrated the feasibility of the proposed composite. The carnauba powder was present in the composite as fill charge. The best formulation, 10%, was chosen to make a parabola of a solar cooker at concentration to produce cooking food. The composite can also be used in the manufacture of decorative panels for the support of televisions, as well as in the manufacture of furniture.