Qi Xingxiang, Xiao Gang, Shen Chao, Ma Xiaotao, Ji Jiachao, Huang Yufei, Yang Yinan, Yao Shendong, Lin Zewan, Tang Jianguo, Zhao Xiaoxu, Ma Pibo, Wang Shichao, Shao Yuanlong
Institute of Hybrid Materials, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, P. R. China.
School of Materials Science and Engineering, Peking University, Beiiing, 100871, P. R. China.
Small Methods. 2025 Sep;9(9):e00921. doi: 10.1002/smtd.202500921. Epub 2025 Aug 4.
Aerogel fiber is considered as outstanding thermal insulation and flexible material for next generation thermal management. However, conventional Supercritical Drying and Freeze Drying methods suffer from energy inefficiency and limited scalability. Herein, a combined solvent exchange and freeze-thaw process is developed to suppress capillary force during ambient pressure drying (by replacing water with low surface tension solvent) while enhancing pore wall strength, enabling scalable fabrication of aramid nanofiber (ANF) aerogel fibers with micron/nanometer graded pores. The resultant fibers exhibit 84.3% porosity, 269.1 m g specific surface area, and 49.6 MPa tensile strength. Knitted textiles (80 × 15 cm) using kilometer-scale multifilament fibers are fabricated, demonstrating a sustained thermal differential >5 °C under bidirectional extremes (either a 100 °C hot plate or -4 °C outdoors) at one-third the areal density of cotton. This energy-efficient scalable manufacturing strategy enables high performance thermal management for industrial and wearable applications.
气凝胶纤维被认为是用于下一代热管理的出色隔热和柔性材料。然而，传统的超临界干燥和冷冻干燥方法存在能源效率低和可扩展性有限的问题。在此，开发了一种溶剂交换和冻融相结合的工艺，以在常压干燥过程中抑制毛细作用力（通过用低表面张力溶剂替代水），同时增强孔壁强度，从而能够可扩展地制造具有微米/纳米级梯度孔的芳纶纳米纤维（ANF）气凝胶纤维。所得纤维的孔隙率为84.3%，比表面积为269.1 m²/g，拉伸强度为49.6 MPa。使用千米级复丝纤维制造了针织纺织品（80×15厘米），在双向极端条件下（100°C热板或室外-4°C），其热差持续>5°C，面密度仅为棉花的三分之一。这种节能的可扩展制造策略为工业和可穿戴应用实现了高性能热管理。
