A Novel Method for Increasing Phase-Change Microcapsules in Nanofiber Textile through Electrospinning

Phase-change textiles can achieve temperature regulation in variable ambient environments, however, augmenting the amounts of phase-change materials (PCMs) in textiles remains a significant challenge due to the occurrence of leakage with higher amounts. Herein, a novel approach is proposed for the fabrication of a hierarchical nanofiber textile embedded with a substantial quantity of phase-change microcapsules (PCMC) using electrospinning. Such nanofiber textile is composed of a polyvinylidene fluoride-hexafluoropropylene fibers (PVDF-HFP) layer and a polyvinyl butyral fibers doped with 60 wt% of PCMC (PVB/PCMC-60) layer. Gratifyingly, doped PCMC shows no signs of rupture and exhibits excellent cycling stability. Furthermore, the incorporation of the PCMC does not affect the spectral characteristics of the PVDF-HFP layer while providing a substantial enthalpy of fusion (92.6 J g⁻¹) to the PVB/PCMC-60 layer. This serves to compensate for the deficiency in radiative cooling capacity and effectively mitigates temperature fluctuations and overheating of the textile. Outdoor test results indicate that the nanofiber textile can achieve temperature drops of 3.7 and 14.8 °C compared to textile without the PCMC (namely PVDF-HFP/PVB) and cotton, and attains a subambient temperature drop of 6.5 °C. Additionally, the nanofiber textile exhibits desirable mechanical strength, flexibility, washability, breathability, moisture permeability, and sun protection.