A growing concern of climate change and waste pollution is causing a shift in products towards green materials. The automotive industry is exploring environmentally friendly alternatives to glass fibers (GF). This research focuses on understanding interactions between constituents of biocomposites made up of basalt fiber (BF) and hemp hurd particle fiber (HF) reinforced polypropylene (PP), and statistically comparing the mechanical properties. The addition of a coupling agent has significantly improved the performance and fiber-matrix interactions in the biocomposite blends. The elastic modulus of some BF/HF/PP mixtures were comparable to the GF/PP composite; however, the GF still outperformed in strength. Rotational and capillary rheometer analysis determined the viscosities of all formulations displaying that basalt composites were consistently lower in viscosity than the glass fiber composite, indicating easier processing conditions.
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Evaluation of the Rheological and Mechanical Properties of Mixed Plastic Waste-Based Composites
This study evaluated the mechanical, thermal, water soak, and rheological properties of mixed plastic waste (MPW) in combination with fibers derived from residual hops bines and coupling agents or dicumyl peroxide (DCP) to form composite materials. Hop bines were pulped to afford individual hop fibers (HF) in 45% yield with 78% carbohydrate content. The MPW comprised mainly of PET, paper, PE and PEVA. Tensile moduli and strength of the formulations ranged between 1.1 and 2.0 GPa and 11 and 14 MPa, respectively. The addition of hops fiber (HF) improved the tensile modulus of the formulations by 40%. Tensile strength was improved by the addition of coupling agents by 11% and this was supported by determining the adhesion factor by dynamic mechanical analysis. However, the addition of DCP resulted in a reduction of tensile properties. The melt properties of the formulations showed shear thinning behavior and followed the power-law model. The water absorption tests for most of the MPW formulations gave an 11% weight gain over 83 d except for the DCP treated composites (14–16%). The fabricated composites can be used in non-structural applications such as (garden trim, siding, pavers, etc.).
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- Award ID(s):
- 1827364
- PAR ID:
- 10359076
- Date Published:
- Journal Name:
- Waste and Biomass Valorization
- ISSN:
- 1877-2641
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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