Baobab shell powder as a bio-filler in HDPE composites: mechanical, and physical properties

Daniel S. Sudi; Haruna Wante; Ndubuisi Mbada; Isah Baba; Bamidele Boluwatife; Solomon Adeleke

doi:10.61298/rans.2025.3.2.213

Authors

Daniel S. Sudi
Department of Metallurgical and Materials Engineering, Air Force Institute of Technology, Kaduna, Nigeria
Haruna P. Wante
[email protected]

Plasma Technology Research Centre, Department of Physics, Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
Ndubuisi Mbada
Department of Metallurgical and Materials Engineering, Air Force Institute of Technology, Kaduna, Nigeria
Isah Baba
Department of Metallurgical and Materials Engineering, Air Force Institute of Technology, Kaduna, Nigeria
Bamidele Boluwatife
Department of Metallurgical and Materials Engineering, Air Force Institute of Technology, Kaduna, Nigeria
Solomon Adeleke
Department of Metallurgical and Materials Engineering, Air Force Institute of Technology, Kaduna, Nigeria

Keywords:

Baobab shell powder (BSP), Lignocellulosic materials, High-density polyethylene (HDPE), Bio-filler

Abstract

This study develops and characterizes high-density polyethylene (HDPE) composites reinforced with 0–20 wt% baobab shell powder (BSP) as a sustainable bio-filler. Composites were fabricated via compression molding and assessed for mechanical, physical, and chemical properties. XRF analysis revealed high metal oxide content in BSP—K2O (29.32%), MgO (16.27%), CaO (12.42%), Al2O3 (12.12%), and SiO2 (11.73%)—indicating multifunctional potential. FTIR confirmed lignocellulosic functional groups (O–H, C–H, C=O, C–O). Tensile strength peaked at 10.996 N/mm2 (20 wt%, +6.14% vs. neat HDPE); yield strength peaked at 26.35 N/mm2 (15 wt%), suggesting improved matrix interaction. Flexural strength dropped to 2.24 N/mm2 at 10 wt% but stabilized thereafter; elongation at break fell from 37.74% to 7.87%, indicating increased rigidity. Impact energy dropped from 4.0 J to 1.63 J, while hardness and density rose from 11.36 to 28.66 N/m2 and 0.87 to 0.93 g/cm3, respectively. Water absorption remained low until day 6, then rose sharply to ~20% (20 wt%) by day 8 due to interfacial degradation. Composites with ≤10 wt% BSP showed better moisture resistance. The results demonstrated that BSP enhances stiffness, hardness, and tensile strength but reduces ductility and impact resistance, making it suitable for non-structural applications in automotive, packaging, and sustainable construction.

Dimensions

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