Recycled hdpe/short coconut fiber composites: effect of coupling agent and fiber loading

The growing concern regarding mitigation of the environmental impacts caused by human activities has led to the development of new technologies. The use of natural fibers as reinforcement in composite materials is an alternative to reduce environmental pollution and contribute to the reduction of these impacts. Therefore, this article reports the analysis of the effect of maleic anhydride-grafted polyethylene (MAPE) as a coupling agent and coconut fiber filler on the physical-mechanical, chemical, and morphological properties of high-density polyethylene composites produced from recycled HDPE/coconut fiber. In this study, rHDPE/MAPE/coconut fiber composites (coconut fiber content: 20 and 30% m/m) and compatibilizer (5% m/m) were prepared in a Teck Tril twin screw extruder (model DCT 20-40). After extrusion of the materials, the composites were crushed and conditioned. The characterization of these materials was carried out through measurement of MFI, density, hardness and water absorption through Fourier-transform infrared spectrometry (FTIR)and scanning electron microscopy (SEM) tests. The results indicated thatwith the addition of higher fiber contents, the hardness and water absorption increased, but the density of the materials was not associated with significant variations. The presence of MAPE improved fiber/matrix adhesion through physical interaction, as indicated by SEM, which showed no change in infrared peaks. With the addition of filler, the rHDPE/MAPE/coconut fiber composites had increased MFI. The study showed that coconut fiber and rHDPE composites can be alternatives for the sustainable reuse and recycling of these wastes.