Resumen de Valorización de residuos queratínicos para la obtención de materiales biocompuestos
Ahmed Rahhali
Materials derired from chicken feathers could be used advantageously in composite building material apptications. Such applications could potentially consume the five billion pounds of feathers produced annually as a by-product of the U.E. poultry industry. This study deals with the preparation and characterization of thermoplastic composites using polypropylene (PP), h¡gh density polyethylene (HDPE), ethylene-vinyl acetate (EVA and polylactic acid matrices (PLA) and including whole chicken feathers as reinforcement. The behaviour of the composites was determined in terms of physical and mechanical properties, hare been characterized in order to determinate the optimal manufacturing conditions of temperature, mixing time and mixing speed to acquire the best tensile properties, which were related to the fibre-matrix compatibility analysed by Fourier transfom infrared spectroscopy and scanning electron microscopy. The results harve shown tha the addition of micronized chicken feather (20%) to thermoplastic matrices, increases stiffness and provides a more brittle behavior. Ethylene Vinyl Acetate (EVA) matix also shows the ability of interacting with chicken feather, thus providing better tensile properties (tensile strength and toughness) than PP and HDPE. Optimal manufacturing conditions are obtained with a mixing time around 5 minutes, a mixing speed of 50 rpm and with a temperature values of 160ºC HDPE , 12OºC for EVA and 170ºC for PP. FTIR spectoscopy and SEM micrographs analysis show results that agree with the properties obtained for the tensilee properties of each one of studied composite materials, Furthermore it ¡s observed that the addition of chicken feathers into the thermoplastic matrices results in a slight increase in the stiffness when small amounts of chicken feathers (5-10% vol/vol) were incorporated into the composites. Tensile strength at maximum load, elongation at break and toughness properties decreased when the chicken feather concentation was increased. Results for chicken feaher-polypropylene composites were analogous to chicken feather-high-density polyethylene and chicken feather-polylactic acid composiles. The Fourier transform infrared spectroscopic study and the scanning electron micrographs suggest that the insufficient compatibility of chicken feather and polymer matrices is the main reason for the decrease in tensile properties. We report on the detailed analysis of chemical modifications and strutural changes in the composites, as a result of photodegradation in a Xenon test chamber.
