Multi-temperature responsive phase-change wood-plastic composites with enhanced thermal and mechanical properties for sustainable building materials

The extreme temperature fluctuations and growing energy demand caused by global climate warming have placed higher demands on the thermal management capabilities of materials. To achieve a dual temperature response (20–50 °C), we utilized the tubular structure of halloysite nanotubes (HNTs) and constructed a phase-change thermal layer with a special spider-web structure on the surface of the microcapsules through interface condensation and electrostatic self-assembly, thus preparing novel MicroPCMs (H-MicroPCMs). H-MicroPCMs exhibit excellent thermal storage (ΔH_m = 146.3 J/g) and shape stability. The dual temperature response enhances their adaptability to variable thermal conditions, contributing to improved energy efficiency in practical applications such as climate-responsive materials and energy-saving building systems. Furthermore, the spider-web structure on the surface of H-MicroPCMs formed continuous thermal link in multi-temperature-responsive wood-plastic composites (H-WPCs). The thermal conductivity and energy storage efficiency of H-WPC 40 (with 40 % H-MicroPCMs) increased by 55.01 % and 84.64 %, respectively. Meanwhile, the spider-web phase-change layer of H-MicroPCMs enhanced the interfacial adhesion between PBAT and wood powder, resulting in a 25.62 % increase in bending strength and a 133.40 % increase in bending modulus of H-WPC 40. Therefore, H-WPC offers an innovative solution to address extreme weather conditions caused by global climate change. It holds significant potential for energy-efficient building materials and smart building systems, enhancing the utilization value of wood processing residues and playing a crucial role in promoting green buildings and sustainable development.