Nano-hybridized phase change material melt-spun fibers and fabrics with radiative cooling/solar heating for efficient all-weather personal smart thermal regulation

Personal smart thermal regulation is crucial for maintaining all-weather comfort in functional textiles. Phase change materials (PCMs) are widely used in fabrics for their energy storage and release capabilities but suffer from poor heat resistance, which limits their application in melt-spun fiber fabrication. Herein, form-stable PCMs are synthesized via molecular chain structure selection and nano-hybridization, enabling high-temperature melt-spun polypropylene (PP)-based phase change fibers (PCFs). Meanwhile, a dual-mode fabric was further fabricated via core-shell yarn weaving, with PCFs as core and two functional PP blend fibers (TiO₂@h-BN for radiative cooling, CNTs for solar heating) as shell. Results demonstrate that the PCMs exhibit excellent heat resistance at 260 °C for 40 min, high enthalpy (141.3 J·g−1), and excellent phase change stability after simulated thermal cycling over 100 times. The tensile strength of functional fibers is greater than 2.0 cN·dtex−1. The dual-mode fabric exhibits a thermal response time of 462 s (maximum temperature difference of 5.5 °C) in hot environments, and an exothermic duration of 300 s (maximum temperature difference of 3.2 °C) in cold environments. Moreover, it delivers efficient cooling (7.2 °C) and heating (32.7 °C) performance under sunlight compared with pure PP fabric. The fabric can withstand multiple washing cycles at room temperature. These dual-mode fabrics exhibit significant potential for personal thermal comfort and open up new possibilities for the commercial production of all-weather smart textiles.