Wood-plastic composites (WPCs) are recognized for their long lifespan, lightweight design, good resistance to corrosion and moisture, and eco-friendliness. They are ideal for various applications, making significant contributions to the industry. WPCs samples were manufactured using different weights and particle sizes for three types of wood: poplar, cypress, and Platanaceae. High-density polyethylene (HDPE) and maleic anhydride (MAPE) were added in specific proportions to produce WPCs using the Taguchi design of experiments. Injection-molded samples were obtained through the injection molding process. Additionally, pure samples of HDPE were prepared for comparison with the polymer composites. The main effects of the signal-to-noise ratio analysis and the optimal values for each mechanical property (tensile strength, elongation at break, flexural strength, and impact strength) were determined. ANOVA results showed that the wood type significantly affected tensile strength, while the weight ratio and particle size had no statistical significance. The types of wood had a noticeable and statistically significant effect on flexural strength, with a contribution of 71.28%, followed by the weight ratio, with a contribution of 11.66%, and the particle size, with a contribution of 2.58%. Additionally, the weight ratio significantly influenced the elongation at break and impact resistance tests. Predictive optimized mechanical characteristic values were calculated, showing that the predictive values were in acceptable agreement with the experimental values with errors smaller than 5%. Optimized tensile strength of 39.94 MPa, elongation at break of 18.41%, flexural strength of 51.71 MPa, and impact strength of 19.27 kJ/m2 were achieved.
