Optimisation of Mechanical and Wear Properties of Cassava Peel-Reinforced Epoxy Composites Using Response Surface Methodology.

This study investigates chemically modified and untreated cassava peel particulates in epoxy composites using Response Surface Methodology (RSM) for systematic optimisation. Composites with varying weight fractions (2–8 wt.%) of treated and untreated cassava peel were fabricated and tested for mechanical and wear properties. RSM with a mixed-level factorial design developed quadratic models relating weight fractions and treatments to composite performance, with multi-response desirability optimisation identifying the optimal formulation. Results demonstrate that NaOH-treated composites exhibit significantly superior properties, with average improvements of 49.1%, 173.9%, and 50.0% in tensile, flexural, and impact strengths, respectively. XRF analysis identified Fe and Ca as dominant elements contributing to enhanced interfacial bonding. RSM models showed excellent predictive capability (R² = 0.856–0.998), with ANOVA revealing treatment as the most significant factor for tensile (p = 0.0195), flexural (p = 0.0344), and wear properties (p = 0.0080). Multi-response optimisation identified a 6 wt.% treated composite as optimal, achieving the highest desirability (0.7846) with maximum tensile (26.5 MPa) and flexural (89.41 MPa) strengths, high impact strength (76 J/m), and acceptable wear resistance (0.0135 g). Model validation confirmed strong prediction accuracy, with property estimates for untested formulations (3–7 wt.%) providing future guidance. These findings demonstrate that RSM provides a robust framework for optimising agro-waste composites, with chemical treatment being critical for enhanced performance in sustainable engineering applications.

Cassava peel, biodegradable material, chemical modification, Eco-friendly, Response Surface

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