Fast Solar-to-Thermal Conversion/Storage Nanofibers for Thermoregulation, Stain-Resistant, and Breathable Fabrics

Abstract

Flexible/foldable, self-supporting, porous, and wearable bifunctional fabrics for sunlight heating and phase change temperature control are designed and constructed for wearable thermal management. In this study, coaxial fibers with polyvinylidene fluoride polymer solution uniformly doped with Cu7S4 as sheath and n-eicosane as core components are fabricated by electrospinning technology. Remarkably, based on the fast solar-to-thermal conversion of the photothermal conversion material, the as-obtained fabric provides sunlight heating for an extra warmth of 25 °C within 1.5 min. Besides, active temperature control via fabric internal phase transformation reduces the daily temperature fluctuations, which is superior to that of the normal and traditional cotton fiber. Impressively, the present bifunctional fabric possesses both better thermal comfortability, including breathability, sweat wicking, and stain resistance, and high durability against wash and soak over 120 h, suggesting its great potential in wearable technologies for thermal regulation.

A highly transparent and photothermal composite coating for effective anti-/de-icing of glass surfaces

“…Cu 7 S 4 photothermal nanoparticles were synthesized according to our previous work. 30 0.2 g of polyvinylpyrrolidone and 0.2 g of Cu(CH 3 COO) 2 ·H 2 O were dissolved in 30 mL of deionized water and stirred for 30 min, then 10 mL of NaOH (1 M) aqueous solution was added and the stirring was continued for 30 min. When a blue precipitate appeared in the solution, 10 mL of ascorbic acid (0.3 M) aqueous solution was quickly added to the mixed solution, heated to 55 °C and stirred for another 30 min.…”

A Trimode Thermoregulatory Flexible Fibrous Membrane Designed with Hierarchical Core–Sheath Fiber Structure for Wearable Personal Thermal Management

“…However, the thermal enthalpy still remains at an ideal level. Figure c shows that the melting enthalpy of EPU@PW is significantly higher than the recently reported results by electrospinning (in a reasonable temperature range for human life between 22 and 46 °C), − ,− which reveals that EPU@PW is a promising candidate for a responsive thermoregulatory textile. As seen in Figure h, the DSC thermograms exhibit a favorable coincidence regarding the locations and intensities of the melting and cooling peaks in 50 cycles, demonstrating the stable reversibility of the phase change behavior.…”

“…(b) Melting and freezing enthalpy of the corresponding membranes. (c) A comparison of melting enthalpy from the latest reported phase change membranes by electrospinning. − ,− (d, e) Representative IR thermal images in the heating and cooling process, respectively. (f, g) Temperature evolution plots in the heating and cooling process, respectively.…”

“…Coaxial electrospinning has been explored to produce core–sheath structured phase change fibers. In this process the PCMs are encapsulated in the center of the fiber to solve the leakage issue. − Additionally, the high aspect ratio of the ultrafine fibers endows the prepared composite membranes with favorable flexibility. Most importantly, the large specific surfaces of the fibrous membrane provide a platform for functionalized surface modifications.…”

Bioinspired Bola Polysiloxane for Wettability, Breathability, and Softness in Fabrics

“…The amount of fabric softeners is increasing due to their capability of reducing fabric roughness and fiber entanglement. − Polydimethylsiloxane (PDMS) had become the most widely used finishing agent because of its unique Si–O helical molecular structure, , which can wind on the fabric surface, making it easy to form a soft film. − Unfortunately, contrary to the Si–O structure, the H atoms on the two methyl groups connected to the Si atoms are staggered due to the atomic repulsion force. − Therefore, the O atoms cannot form hydrogen bonds with the H atoms of water molecules, resulting in strong hydrophobicity, thus leaving humans feeling hot and sticky. Therefore, personal comfort is difficult to satisfy. − …”