MXene Functionalized Kevlar Yarn via Automated, Continuous Dip Coating

Abstract The rise of the Internet of Things has spurred extensive research on integrating conductive materials into textiles to turn them into sensors, antennas, energy storage devices, and heaters. MXenes, owing to their high electrical conductivity and solution processability, offer an efficient way to add conductivity and electronic functions to textiles through simple dip coating. However, manual development of MXene‐coated textiles restricts their quality, quantity, and variety. Here, a versatile automated yarn dip coater tailored for producing continuously high‐quality MXene‐coated yarns and conducted the most comprehensive MXene‐yarn dip coating study to date is developed. Compared to manual methods, the automated coater provides lower resistance, superior uniformity, faster speed, and reduced MXene consumption. It also enables rapid coating parameter optimization, resulting in a thin Ti₃C₂ coating uniform over a 1 km length on a braided Kevlar yarn while preserving its excellent mechanical properties (over 800 MPa) and adding Joule heating and damage sensing to composites reinforced by the yarns. By dip‐coating five different yarns of varying materials, diameters, structures, and chemistries, new insights into MXene‐yarn interactions are gained. Thus, the automated dip coating presents ample opportunities for scalable integration of MXenes into a wide range of yarns for diverse functions and applications.