Recycling of Nonwoven Waste Resulting from the Manufacturing Process of Hemp Fiber-Reinforced Recycled Polypropylene Composites for Upholstered Furniture Products

Waste recycling is a solution that reduces the environmental impact of waste landfilling or incineration. The aim of this paper is to investigate both the effect of incorporating recycled fibers obtained by defibrating 50/50 hemp/rPP nonwoven waste and the effect of the compatibilizer on the properties of composite materials. Composites incorporating 50% and 100% recycled fibers were treated with 2.5% and 5% maleated polypropylene (MAPP), respectively, and compared to both the untreated composites and the composite obtained by thermoforming from the nonwovens that generated the waste. The incorporation of 50% and 100% recycled fibers into composites decreased the tensile strength by 17.1-22.6%, the elongation at break by 12.4-20.1%, the flexural strength by 6.6-9%, and flexural modulus by 10.3-37%. The addition of 5% MAPP showed the greatest improvements in mechanical properties of composites containing 100% recycled fibers, as follows: 19.2% increase in tensile strength, 3.8% increase in flexural strength, and 14.8% increase in flexural modulus. Thermal analysis established that at temperatures ranging between 20 degrees C and 120 degrees C, the composites were thermally stable. SEM analysis revealed good coverage of the reinforcing fibers, and EDX analysis confirmed the presence of the compatibilizing agent in the structure of the composite material.

Automated summary

The aim of this study is to investigate the effects of incorporating recycled fibers and a compatibilizer on the properties of composite materials. The results showed that the inclusion of recycled fibers decreased the tensile strength, elongation at break, flexural strength, and flexural modulus of the composites. However, the addition of a compatibilizer improved the mechanical properties of the composites containing 100% recycled fibers. Thermal analysis revealed good thermal stability of the composites, and SEM and EDX analysis confirmed the presence of the compatibilizing agent in the composite structure.