Revista de Bioprocessamento e Biotécnicas

Statistical Analysis and Mechanical Behavior for Polypropylene Composites Reinforced with Benzoylated Sugarcane Fibres

Abstract

Rosineide Miranda Leão*, Sandra Maria Luz and Andre L Christoforo

Sugarcane fibres, in the form of bagasse, are abundant by-products from the sucro-alcohol industry and are commonly used as reinforcement in composite materials. The main objective of this work concerns the modification of the sugarcane bagasse fibers (in natura and pulps rich in cellulose) by benzoylation. Unfortunately, the natural fibres have hygroscopic properties, causing poor fibre/matrix interaction. In order to encourage non-polar properties in the fibres, this current work is concerned with the feasibility of aromatic group insertion in natural fibre structures using benzoylation reactions. Sugarcane fibres were soaked in aqueous NaOH and mixed with benzoyl chloride. After chemical treatments, the modified sugarcane fibres were characterized by weight gain, Fourier Transformer Infrared-FTIR, Scanning Electron Microscopy SEM, thermal analysis, mechanical tests and statistical analysis. Results show that there was significant weight gain during the first hour of the reaction. Esterification reaction efficiencies were confirmed by FTIR. SEM characterization revealed that the chemical treatment changed the morphology of the fibres. Thermogravimetric-TG curves illustrated different behaviour between modified and nonmodified fibres. Mechanical properties show that the benzoylated fibres insertion caused an increase in the tensile strength in regard to non-modified fibres. Finally, the results for strength obtained from the uniaxial tensile tests demonstrated the effectiveness of treating the fibres with benzoyl groups, with condition C6 providing the best results, followed by condition C7.