Characteristics of Agro Waste Fibers as New Thermal Insulation and Sound Absorbing Materials: Hybrid of Date Palm Tree Leaves and Wheat Straw Fibers

New novel biodegradable natural thermal insulation materials are manufactured from agro-waste materials such as date palm tree leaves and wheat straw fibers as a potential use in buildings’ insulation. Ten fiberboards are prepared, where three of them are loose leaves and the remaining are bound boards. These bound boards can be classified as either single fibers or hybrid. Cornstarch and wood adhesive are used as binders for the fibers. The Thermal conductivity are measured for all fiberboards and found to be in the range 0.045–0.065 W/m K at temperatures 10–60°C, respectively. The Sound absorption coefficient is greater than 0.6 for frequencies greater than 900 Hz for almost all boards, which indicates a very good sound absorption behavior for these hybrid materials. Date palm tree leaves are found to be thermally stable up to about 213°C. Three-point bending tests are also conducted for the hybrid bound boards. The results indicate the potential use of such novel bound fiberboards and their new hybrid ones as new natural materials for thermal insulation and sound absorbing.