Self‐Contained Moisture Management and Evaporative Cooling Through 1D to 3D Hygroscopic All‐Polymer Composites

Abstract Sorption‐based moisture management and evaporative cooling represent emerging technologies with substantial potential for energy‐saving personal thermal management (PTM). However, design of high‐performance and durable hygroscopic composites combining efficient heat dissipation with wearing comfort presents significant challenges. Herein, hygroscopic 1D nanofibers and 2D fabrics are developed using two hygroscopic polymers and crosslinking strategies. The design endows the fabrics with self‐contained properties including excellent hygroscopicity, durability, ductility, breathability, washability, and antimicrobial capability. The fabrics exhibit thickness‐independent moisture sorption and equilibrium water uptake of 1.19 g g⁻¹ in 4 h under 90% relative humidity (RH). About 80% of the absorbed water can be rapidly released through mild heating within 10 min. These high moisture sorption/desorption rates outperform the majority of composite desiccants, enabling up to five sorption/desorption cycles per day under a real sky. The hygroscopic fabrics can reduce apparent temperatures and prevent unsightly sweat stains on clothing, improving thermal and clothing comfort. Furthermore, hygroscopic 3D hierarchical matrices are printed, showcasing the potential to use small amounts of hygroscopic materials to boost moisture sorption. This work advances the controlled fabrication of hygroscopic polymer composites, ranging from 1D nanofibers and 2D fabrics to 3D matrices, highlighting their promising prospects for future sorption‐based PTM applications.