Reduced plasticity and reinforcement of polyvinyl chloride using sawdust powder as a natural filler

This study investigates the use of powdered sawdust from three wood types (Mitragyna ciliata, Aucoumea klaineana and Khaya anthotheca) as a natural filler in polyvinyl chloride composites (PVC) to enhance performance properties such as tensile strength, impact resistance, and hardness compared to non-reinforced PVC composites. The research aims to evaluate the physicochemical characteristics of wood sawdust and its impact on the mechanical properties of polyvinyl chloride (PVC) composites. Wood-plastic composites (WPC) were prepared by incorporating sawdust into the PVC polymer matrix using tetrahydrofuran (THF) as the dissolving solvent, with moulded samples created using silicone gel. The physicochemical properties of the wood sawdust, such as pH, moisture content, dry weight percentage, bulk density, porosity, grain volume, iodine number, and ash content, were analyzed and found to vary significantly across the wood types. Mechanical property assessments revealed no enhancements in the reinforced PVC composites. Tensile strengthvaried by wood type: Mitragyna ciliata (4.73 N/mm²), Aucoumea klaineana (5.69 N/mm²), and Khaya anthotheca (7.50 N/mm²). Similarly, impact resistance showed variations: Mitragyna ciliata (0.21 N-m/mm²), Aucoumea klaineana (0.26 N-m/mm²), and Khaya anthotheca (0.84 N-m/mm²), with an overall hardness of 13.00 N/mm². Statistical analysis consistently demonstrated that sawdustreinforced PVC composites exhibited superior mechanical properties compared to unreinforced PVC. It can be concluded that Khaya anthotheca wood sawdust powder has outstanding overall performance in mechanical properties when compared to the other wood sawdust powdersinvestigated. Therefore, Khaya anthotheca sawdust is recommended for further study in terms of durability, weathering properties, and other environmental conditions to evaluate its suitability as a filler in PVC plastic product manufacturing.