Facile synthesis of high-performance bamboo-based polymer composites with better dimensional stability and enhanced thermal conductivity

Natural bamboo (NB) has inherent limitations, such as low thermal conductivity, tendency of hygroscopic expansion, and susceptibility to mold and mildew attack, which hampers its high value-added applications. This study developed high-performance bamboo-based polymer composites (BPC) by a delignification process combined with impregnation of AlN/BN-Epoxy resin. The thermal conductivity of BPC increased by 155.7% to 0.358 W/(m·K), as compared with NB, whereas hydrophobic modification of the surface reduced the hygroscopic volume expansion to below 3%. Application of pressure optimized the distribution of resin and interfacial bonding that could achieve a tensile strength of 115.61 MPa (10.2% increase compared to NB). Further, BPC showed improved thermal stability with peak pyrolysis temperature of 367.3 °C. Micromorphological analysis confirmed that continuous thermally conductive networks were formed by the alignment of AlN/BN filler in the epoxy matrix. Meanwhile, X-ray photoelectron spectroscopy (XPS) showed the presence of hydrophobic C-F bonds on the modified surfaces. This multi-scale approach could successfully overcome the limitations of bamboo’s performance, endowing BPC with combined thermal capabilities, mechanical strength, and environmental durability. These advancements make BPC a sustainable alternative to conventional underfloor heating substrates and heat dissipation components.