Enhanced Radiative Warming and Thermomechanical Properties of PET filaments and Fabrics via Uniform Dispersion of Photothermal and Far‐Infrared Nanoparticles

Polyethylene terephthalate (PET) fabrics with enhanced radiative warming performance are developed by addressing the long‐standing challenge of nanoparticle agglomeration of zirconium carbide (ZrC) and tourmaline (T) in the PET matrix. This is achieved through surface grafting modification, yielding well‐dispersed and hydrophobic nanoparticles of modified ZrC (HZC) and modified T (HT). As a result, the PET/HT/HZC composites exhibited homogeneous nanoparticle dispersion, which simultaneously enhanced light absorption and far‐infrared (FIR) emission. PET/HT/HZC filaments prepared via the melt spinning process demonstrated tensile strength values exceeding 3.2 cN/tex. Under simulated sunlight, the fabric containing 1 wt.% HT/HZC nanoparticles (F‐PET‐1.0) reached 65.4°C within 150 s, which was 28.4°C higher than pristine PET fabric. Field tests in Shanghai further confirmed the warming effect, with fabric surface temperatures up to 24°C higher than unmodified PET fabrics. Moreover, the FIR emissivity of F‐PET‐1.0 increased to 0.900 after ten washing cycles, corresponding to a 15.2% enhancement compared with pristine PET, potentially contributing to improved thermal comfort and physiological benefits, such as enhanced blood circulation. These results demonstrate that the synergistic incorporation of HT and HZC endows PET fabrics with dual functionalities of sunlight‐responsive warming and FIR‐based healthcare, offering significant potential for advanced thermal textiles.