An investigation of thermal conductivity and sound absorption from binderless panels made of oil palm wood as bio-insulation materials

Oil palm wood is one of the solid wastes available in large quantities, which has been used as non-structural material. Many researchers focus on their material strength and binder selection. However, limited studies investigate oil palm wood as insulation materials. Therefore, this study aimed to evaluate the thermal and sound characteristics of oil palm wood binderless panels as insulation materials. Panels were manufactured from oil palm wood using hot presses with different particle sizes and pressing times. The results indicated that the particle size had a significant effect on the characteristics of the binderless panels but not on pressing times. The coarser particle size enhanced the thermal and sound resistance but decreased density, water resistance, and flexural strength. In addition, the panels with large particles had the least thermal conductivity (0.050 W/mK) and the highest sound absorption coefficient of 0.33. The study also showed that the flexural strength and water absorption of the panels ranged from 4.21 to 8.18 MPa and 84.51%–119.06%, respectively. The findings of this study indicate the feasibility of binderless panels from oil palm wood as insulation materials.