High-performance, renewable thermal insulators based on silylated date palm fiber–reinforced poly(β-hydroxybutyrate) composites

Abstract

Developing insulating materials with minimal environmental impacts and enhanced properties has been the primary challenge in recent years. To address these challenges, date palm fiber (DPF) was treated with a silane coupling agent 3-aminopropyl triethoxysilane and two grafting solvents (acetone and ethanol) via the wet chemical method. The treated fibers were used to prepare poly(β-hydroxybutyrate) (PHB)-based composites via melt blending, thermo-compression molding, and annealing. The insulation properties of these green composites revealed that the silylated fiber composites possess an appropriate thermal conductivity, of 0.0901–0.106 W/(m·K). In cold and hot water, the silylated fiber composites drastically decreased water absorption by 20% and 34%, respectively. The tensile strength of the silylated fiber composites reached 18 MPa owing to improved compatibility, and the highest compressive strength was 48.6 MPa with a filler content of 40 wt%. The heat of combustion for silylated fiber composites ranged from 20.79 to 21.94 MJ/kg. The results indicate that silylated DPF-based PHB composites have potential for use in building engineering.

Keywords

• Green thermal insulator
• Polyhydroxybutyrate
• Silane treatment
• Date palm fiber
• Biodegradable construction material