Enhanced thermal conductivity of UHMWPE by coating boron nitride and polyurethane composites

The development of textile wearable electronics has increased demands and requirements for thermal management materials due to integrated and miniaturized soft equipment. In this work, the surface of ultrahigh molecular weight polyethylene (UHMWPE) fibers was first decorated by polydopamine (PDA) to improve the surface activity and construct a steady interface layer. Then the boron nitride/polyurethane coating surface modified UHMWPE composite yarns with good thermal conductivity were produced using a coaxial wet forming process. The thermally conductive composite yarns demonstrated great mechanical properties (5.09 % strain, 0.79 N/tex strength) and thermal conductivity (0.54 ± 0.02 W·mK⁻¹) with the BN/PU weight ratio of 1. Furthermore, the resistance to failure cycles was taken place, and the composite yarns kept good thermal conductivity after multiple cycles twisting, bending, washing, cooling and heating cycles. By the coaxial wet fabrication, the thermally conductive composite yarns were constructed, offering a viable and trustworthy method for creating polymer-based thermal interface materials with high thermal conductivity.