Thermal insulation using biodegradable poly(lactic acid)/date pit composites

The usage of green insulation in building construction improves the thermal management with respect to buildings and allows the usage of environmentally friendly materials for insulation. Herein, we developed novel green polymer composites using biodegradable poly(lactic acid) (PLA) and date pit powder (DPP) as the building insulation material. The PLA–DPP composites were melted and blended and were subjected to compression molding. Then, they were characterized based on their physical (water absorption), thermal (thermal conductivity, thermal diffusivity, and degree of crystallization), and mechanical properties. Results indicate that the thermal conductivity decreased from 0.0794 to 0.0682 W/m.K when the DPP content increased from 10% to 40% (w/w). Similarly, the thermal diffusivity decreased with the increasing DPP content and became 0.034 mm²/s. However, this increased the water absorption (~5.6% at 40 wt.% in cold water). The compressive strength decreased with the addition of DPP, which was attributed to the filler agglomeration and low compatibility between PLA and DPP. The compressive strength of the PLA–DPP composite was higher than those of the commonly used insulating materials and comparable to those of the construction materials (84.3–64.4 MPa). The characteristics of the PLA–DPP composites indicate that they are stable composites with promising insulation and construction capacity. The composite developed herein could replace traditional insulators and a portion of the concrete in the wall panel, increasing the overall thermal resistance of the wall panel. The developed materials may be used in the handles of kitchen utensils and other materials that require thermal insulation.