Sustainable wood fiber composites with antistatic and high-thermal-conductivity performance for energy-efficient home environments

Abstract

The rapid expansion of the smart home sector has necessitated the development of multifunctional, high-performance materials for intelligent furniture applications. By harnessing lignin as a novel natural binder and multi-walled carbon nanotubes (MW-CNTs) as conductive fillers, this study demonstrates a synergistic strategy to enhance thermal/electrical conductivity while preserving the inherent sustainability of biomass materials. Specifically, we introduce a lignin-mediated biocomposite addressing three critical challenges: escalating electrostatic discharge risks in indoor environments, thermal management requirements for integrated smart devices, and inefficient heat transfer in low-temperature radiant floor systems. The composites were fabricated using poplar wood flour—a renewable agroforestry residue—and MW-CNTs, with lignin serving as a dual-functional agent to eliminate synthetic adhesives. Alkaline pretreatment enhanced cellulose reactivity by removing hemicellulose, while lignin formed robust interfacial bonds with wood fibers and MW-CNTs through hydrogen bonding and interactions during hot-pressing. Mechanical blending promoted the homogeneous dispersion of MW-CNTs, and hot-pressing induced physical interlocking and chemical cross-linking. Characterization revealed exceptional mechanical properties (static flexural strength: 126.56 MPa; tensile strength: 118.65 MPa) and functional performance, including electrical conductivity (3.16 × 10⁵ Ω m) and thermal conductivity (0.806 W (m⁻¹ K⁻¹)). Life cycle assessment indicates that biocomposites have a lower environmental impact than both polyethylene and poly(vinyl chloride). This unique combination of properties makes biocomposites an effective antistatic and thermally conductive household material that shows strong potential as a replacement for traditional petroleum-based materials and represents an important step towards a safer, more environmentally sustainable and energy-efficient future.