State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China.
Nanofibers Research Center, Modern Textile Institute, Donghua University, Shanghai, 200051, China.
Small. 2017 Mar;13(10). doi: 10.1002/smll.201603151. Epub 2017 Jan 6.
The filtration capacity of fibrous media for airborne particles is restricted by their thick diameter, low porosity, and limited frontal area. The ability to solve this problem would have broad technological implications for various air filtration applications; despite many past efforts, it remains a great challenge to achieve. Herein, a facile and scalable strategy to fabricate the ripple-like polyamide-6 nanofiber/nets (PA-6 NF/N) air filter via combining electrospinning/netting technique with receiving substrate design is demonstrated. This proposed approach allows the scaffold filaments to orderly embed into 2D PA-6 nanonets layer with Steiner-tree structures and nanoscale diameter of ≈20 nm, resulting in the ripple-like membrane with extremely small pore size, highly porous structure, and hugely extended frontal surface, by facilely adjusting its pleat span and pleat pitch. These unique structural advantages enable the ripple-like PA-6 NF/N filter to filtrate the ultrafine particles with high removal efficiency of 99.996%, low air resistance of 95 Pa, and robust quality factor of >0.11 Pa ; using its superlight weight of 0.9 g m and physical sieving manner. This approach has the potentialities to give rise to a novel generation of filter media displaying enhanced filtration capacity for various applications thanks to their nanoscale features and designed macrostructures.
纤维介质对空气传播颗粒的过滤能力受到其直径大、孔隙率低和有效过滤面积有限的限制。如果能够解决这个问题，将对各种空气过滤应用产生广泛的技术影响；尽管过去做了很多努力，但要实现这一目标仍然是一个巨大的挑战。在此，通过将静电纺丝/网技术与接收基底设计相结合，展示了一种制造波纹状聚酰胺-6 纳米纤维/网（PA-6 NF/N）空气过滤器的简单且可扩展的策略。该方法允许支架纤维以有序的方式嵌入具有 Steiner 树结构和≈20nm 纳米直径的 2D PA-6 纳米网层中，从而通过简单地调节其褶皱跨度和褶皱间距，在波纹状膜中形成具有极小孔径、高多孔结构和极大扩展表面积的波纹状结构。这些独特的结构优势使波纹状 PA-6 NF/N 过滤器能够过滤超细颗粒，其去除效率高达 99.996%，空气阻力低至 95Pa，质量因子>0.11Pa；其超轻重量为 0.9g/m，采用物理筛分方式。由于具有纳米级特征和设计的宏观结构，这种方法有可能为各种应用带来新一代过滤介质，从而提高过滤能力。
