Obtenção e avaliação de um compósito usando fibra de caroá (Neoglaziovia variegata) e matriz fenólica com PET pós-consumo.

Abstract

One of the great challenges facing humanity is the reuse total polymeric material which is normally discarded, causing a significant environmental impact. The PET quite a thermoplastic polymer applied in the packaging industry, which generates a discharge can be reused not only in the production of new packaging but also utilized as raw materials to obtain composite materials reinforced with vegetable fibers. Caroá fiber emerges as a material of great importance and can be used as reinforcement in the manufacture of fibreboard with industrial applications. The objective of this work was the fabrication of a polymer matrix composite using resol / PET post-consumer fiber reinforced caroá (Neoglaziovia variegata) for the use and applications compatible with the properties found. It was used percentages between 10 and 70% PET solubilized caroá fibers with an average diameter of 0.17 mm, untreated, between 4 and 21%, for a molar ratio of 1:3 phenol resin phenolic / formaldehyde. The fibers were assembled into continuous layers oriented in the longitudinal and transverse direction and interleaved with resin. The phenolic resin was cured with a temperature of 90 0C and pressed by a force of 10 tons during 3 h. The tests performed were: density, tensile, bending, linear expansion, swelling during 2 h and 24 h, thermal analysis (DSC) and (TG) and scanning electron micrograph (SEM). The solubility reached the maximum percentage of 33% to a molar ratio of 1:3 phenol / formaldehyde. The PET was the material which contributed to the increase in density. Traction in the content of PET solubilized below 30%, increased in the composite, the tensile property above the minimum required (0.40 MPa). Flexion increased fiber content caroá, unlike other materials, favored an increase above 18 MPa. However, increasing PET content caused more resistance for the maximum tensile modulus (MOR) of the resin and for the modulus of elasticity (MOE) in flexion increased resin content led to greater resistance than PET. Smaller values of the linear expansion of the composite were obtained in the treatments of PET solubilized percentage below 30%. The matrix with solubilized PET content above 30% led to discontinuation of the resin and greater water absorption. The greatest swelling results after 2 h and 24 h in the composite, were caused with the PET content above 30% soluble in the matrix. In the test scanning calorimetry (DSC) increase the content of PET tends to decrease the glass transition temperature (Tg) of the phenolic matrix. In the test results of thermogravimetry (TG) at the maximum intensity loss in mass degradation was 550 0C. In scanning electron microscopy (SEM) best accessions fiber / resin are related treatments solubilized PET content below 30%.