Compósitos poliméricos reforçados por fibras de l: efeitos de tratamentos químicos na adesão interfacial

Abstract

The growing concern with sustainability foments the development of research regarding to polymer composites reinforced with natural fibers, which represent an ecological alternative to the commonly used synthetic ones. However, natural fiber reinforced polymer composites present obstacles regarding both structural and nonstructural applications, due to their weak fiber/matrix interfacial interaction. To minimize this problem, chemical treatments can be performed to improve adhesion and consequently the technological properties of the composite. In this sense, the objective of this research is to study the effects of chemical treatments in polymer composites reinforced with licuri fibers, using solutions of sodium hydroxide, potassium permanganate and hexane, to improve the interfacial adhesion between the licuri fiber (Syagrus coronata) and the orthophthalic polymeric matrix based on polyester. The composites were made by hand lay-up. The water absorption characteristics of the laminates were obtained by immersion in distilled water for a period of 1800 hours. The mechanical tests were evaluated in terms of tensile, flexural, and Short-Beam properties. Fracture analysis of the samples was performed by scanning electron microscopy (SEM). The results obtained showed that the chemical treatments carried out in the present work are efficient in reducing the moisture absorption of the composites and improving the shear and flexural properties.