Research Article

Influence of Palm Kernel Shell Particle Size on the Performance of Waste Polystyrene Matrix Composites

Usman, M.1*, Ishiaku S. U.2, Umaru H. I3, Lawal N2
1 Ahmadu Bello University Zaria
2 Department of Polymer and Textile Engineering, Ahmadu Bello University, Zaria, Nigeria
3 Department of Polymer Textile Engineering, Ahmadu Bello University, Zaria
* Corresponding author: mosesu84@gmail.com
Published: Jun, 2026
DOI: 10.67637/njt.2026.t2nozl2x
Pages: 47-59
Views: 22
Downloads: 30

Abstract

The valorisation of agricultural and plastic wastes provides a sustainable path for developingeco-friendly composite materials. This study investigates the influence of palm kernel shell(PKS) particle size on the physical, mechanical, and morphological properties of wastepolystyrene matrix (WPS) composites. PKS particles of 100 μm, 200 μm, and 300 μm wereincorporated at a constant filler loading of 10 wt.% and fabricated using a compressionmoulding machine. In addition, scanning electron microscopy (SEM) analysis was selectivelycarried out on composites containing 100 μm and 300 μm PKS particles at filler loadings of 10wt.% in order to use morphological properties to elucidate the observed mechanical propertiesusing the best-performing and worst-performing composite samples based on the physical andmechanical properties. The composites were characterised by physical, mechanical, andmorphological properties as per ASTM standards to determine density, water absorption,tensile, flexural, impact, and hardness properties, and morphology using scanning electronmicroscopy (SEM). The result shows that density does not consistently increase or decreasewith particle size due to the effects of agglomeration and porosity. However, 200 μm showeda better density of 1.13 g/cm³ compared to 100 μm and 300 μm, with density values of 1.11g/cm³ and 1.12 g/cm³. Water absorption increased significantly in composites containing 200–300 μm particles, indicating increased void formation and weaker filler–matrix interactions,while 100 μm had the lowest water absorption (1.81%). The results also showed a decrease intensile strength, tensile modulus, and elongation at break, flexural strength, flexural modulus,and impact as the filler particle size increased. The smallest particle size of 100 μm showed thebest values for tensile strength, tensile modulus, elongation at break, flexural strength, flexuralmodulus, and impact, with the corresponding values of 17.27 MPa, 2.75 GPa, 8.46 %, 50.12MPa, 2832.23 GPa, 0.35 J, while hardness has the best value of 53.8 HV at 300 μm,respectively. These improvements with 100 μm were attributed to their larger surface area,better filler dispersion and improved interfacial adhesion between PKS particles and the WPSmatrix, as confirmed by SEM observations. On the other hand, coarse particles introducedstress concentration sites, voids, and microdefects, which promoted brittle failure. Therefore,the study concludes that 100 μm PKS particles are optimal for producing lightweight WPScomposites with balanced physical and mechanical properties, suitable for non-structuralapplications, while contributing to sustainable waste management and waste upcycling.

Keywords

Palm kernel shell waste polystyrene (WPS) composites particle size effect compression moulding physical properties mechanical properties waste valorization sustainable composites biofiller

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How to Cite

M., U., U., I. S., I, U. H., & N, L. (2026). Influence of Palm Kernel Shell Particle Size on the Performance of Waste Polystyrene Matrix Composites. Nigerian Journal of Textiles, 12(1), 47-59. https://doi.org/10.67637/njt.2026.t2nozl2x

U. M., I. S. U., U. H. I, and L. N, "Influence of Palm Kernel Shell Particle Size on the Performance of Waste Polystyrene Matrix Composites," Nigerian Journal of Textiles, vol. 12, no. 1, pp. 47-59, June 2026. doi: 10.67637/njt.2026.t2nozl2x

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