Optimization of Material Composition and Compression Molding Process Parameters to Maximize Mechanical Properties of Recycled Polypropylene (r-PP) Composite Reinforced with Ironwood Powder

Abstract

It could potentially be possible to create more sustainable materials by using wood waste as reinforcement in recycled polymer material. This study aims to optimize material composition and compression molding parameters to maximize the mechanical properties of recycled polypropylene composites reinforced with ironwood powder using the Taguchi orthogonal L9 design of experiment. The composites were manufactured in two-step extrusion and compression molding. The parameter levels used in this study are ironwood loading of 10%, 20%, and 30% with the addition of three different levels of coupling agent and manufactured using the molding temperature of 165℃, 175℃, 185℃ as well as pressure holding time of 3 minutes, 6 minutes, and 9 minutes. Tensile testing was conducted in accordance with ASTM D 638 type V standard. The S/N ratio analysis revealed different optimum parameters for tensile strength and elastic modulus. Therefore, the grey relation analysis was performed. It was found that the optimum composition and parameter variation for tensile strength and elastic modulus are 10% mass fraction of ironwood, 3% of MAPP, molding temperature of 165℃, and pressure holding time of 9 minutes. The ANOVA indicated wood powder loading as the most significant parameter on the mechanical properties of the composite. The material composed of recycled polypropylene and waste of ironwood can be considered a promising sustainable material for engineering-related applications.