Desenvolvimento de um compósito eco-friendly de ABS reforçado com resíduos proveniente da fibra da palmeira para aplicação em impressão 3D

Abstract

In the present work, the objective is to evaluate the potential to valorize the solid waste of the Australian royal palm tree for use as reinforcement in the acrylonitrile butadiene styrene (ABS) matrix and to develop a composite filament that is more environmentally friendly. The composite filaments were processed using a thermokinetic mixer and then processed by a mini extruder using different amounts of fibers (5, 10, 15 and 20% wt). The effect of fiber contents on the morphological, chemical and thermal properties was evaluated, and an environmental analysis was performed using life cycle assessment (LCA). Pristine ABS presented no porosity, while the composite filaments showed a porous structure due to the presence of fibers and higher amounts of fibers induced pores with diameter less than 50 μm. ABS and filament composites presented similar FTIR spectra; however, the hydrogen bonding coefficient indicated a better fiber-matrix interaction for the ABS/15%Palm tree composition, increasing by 42%wt compared to ABS. The composite filaments presented a slight decrease in thermal stability, which does not compromise their processing temperature, while Tg presented similar values to pristine ABS. The life cycle assessment demonstrated beneficial environmental gains with the incorporation of natural fibers into the ABS matrix. The categories that showed the most environmental gains were: agricultural land occupation, ozone layer depletion, urban land occupation, water depletion, chemical oxidant formation, and fossil depletion. The results of the water absorption test presented an increase in the water absorption rate of the composite filaments according to the fiber loading, the ABS/20%Palm composition had the highest water absorption result. The composite filaments were successfully printed on a mini extruder showing the viability of using the developed filaments and new applications may be promoted. Pristine ABS and the composite filaments were analyzed to obtain the mechanical properties, such as tensile strength, strain and modulus of elasticity, it was observed that by increasing the fiber content in the ABS matrix there was a reduction in the mechanical properties of the composite filaments. The biodegradation test of the specimens of pristine ABS and the composite filaments presented a loss of mass, confirming that the incorporation of fiber in the matrix was favorable for the material to be degraded, the composite filaments obtained a mass loss of almost 25% wt, when compared to the initial weight. Thus, enhancing the use of palm fibers in the ABS matrix presents a low-cost alternative for filaments production and may expand 3D printing applications with more sustainable materials that could enable new applications in the area of additive manufacturing.