Liu Yibo, Jia Chao, Zhang Han, Wang Haiyang, Li Pan, Jia Luna, Wang Feng, Zhu Pengfei, Wang Hao, Yu Lu, Wang Feipeng, Wang Lingxiao, Zhang Xin, Sun You, Li Bo
State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, P. R. China.
Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Shenzhen 518055, P. R. China.
ACS Appl Mater Interfaces. 2021 Jul 28;13(29):34773-34781. doi: 10.1021/acsami.1c04253. Epub 2021 Jul 19.
Particulate matter of 0.3 μm in diameter (PM) poses a serious threat to the environment and human beings. Ultrathin and -light nanofibrous filters with excellent filtration properties can significantly prevent the detrimental effects of these particles. Here, we develop free-standing polyamide PA-66 ultrafine nanofiber papers for PM filtration using effective and scalable blow and electro-blow spinning techniques. The smallest average fiber diameter is 61.7 nm, which is 2-3 orders of magnitude smaller than that of conventional textiles. Poly(ethylene terephthalate) nonwovens are selected to fabricate free-standing nanofiber papers of various polymers, including polyamide, poly(methyl methacrylate), poly(vinylpyrrolidone), and poly(ethylene oxide) owing to the smooth surfaces of the nonwovens. This underlying principle can be used to create similar free-standing nanofiber papers from other commodity polymers in the future. Mechanisms of capturing particulate matter with different nanofiber morphologies are discussed. Salt and oil particulates are used to characterize the filtration properties. PA-66 papers are promising reusable filters owing to their mechanical particle-capture mechanism. The blow-spun PA-66 papers show filtration performance of 98.75% efficiency and a pressure drop of 125.44 Pa owing to the "slip" effect caused by the ultrasmall diameter. In the electro-blow spinning process, a supplementary voltage supply is conducive to separating nanofiber bundles into random-oriented nanofibers. Electro-blown spun papers possess an ultrahigh efficiency of 99.99% with a reduced areal density of 0.9 g m. These PA-66 papers can be used in a variety of applications, such as reusable personal protective equipment, industrial waste gas treatment, and central ventilation purification systems.
直径为0.3微米的颗粒物（PM）对环境和人类构成严重威胁。具有优异过滤性能的超薄轻质纳米纤维过滤器可以显著防止这些颗粒的有害影响。在此，我们使用有效且可扩展的吹纺和电吹纺技术开发用于PM过滤的独立式聚酰胺PA-66超细纳米纤维纸。最小平均纤维直径为61.7纳米，比传统纺织品小2-3个数量级。由于聚对苯二甲酸乙二酯非织造布表面光滑，因此选择其来制造包括聚酰胺、聚甲基丙烯酸甲酯、聚乙烯吡咯烷酮和聚环氧乙烷在内的各种聚合物的独立式纳米纤维纸。这一基本原理未来可用于从其他商用聚合物制备类似的独立式纳米纤维纸。讨论了不同纳米纤维形态捕获颗粒物的机制。使用盐和油颗粒来表征过滤性能。PA-66纸因其机械颗粒捕获机制而有望成为可重复使用的过滤器。由于超小直径导致的“滑移”效应，吹纺PA-66纸的过滤效率为98.75%，压降为125.44帕。在电吹纺过程中，辅助电源有助于将纳米纤维束分离成随机取向的纳米纤维。电吹纺纸具有99.99%的超高效率，面密度降低至0.9克/平方米。这些PA-66纸可用于多种应用，如可重复使用的个人防护装备、工业废气处理和中央通风净化系统。
