Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, PR China.
Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, PR China.
Sci Total Environ. 2020 Jul 10;725:138297. doi: 10.1016/j.scitotenv.2020.138297. Epub 2020 Mar 28.
Airborne particulate matter (PM) pollution has raised serious concerns over both the global climate and public health. Therefore, there is an urgent need for air filters of high-efficiency and energy-saving. Pore structure optimization and electret enhancement are feasible means to improve their filtration performance. Herein, a novel sandwich-structured electret composite filter with a low pressure drop and robust filtration stability was successfully designed and fabricated. The composite filter was composed of fluffy PS microfibers with large electric resistivity and high porosity, and PAN nanofibers with high polarity and small pore size. Benefiting from the fluffy structure constructed by electrospinning at the right humidity, the tortuous pore channels created by the appropriate mixing of microfibers and nanofibers, and the abundant static charges generated by the hybrid of polar and nonpolar polymer materials, the PS/PAN/PS composite filter possessed a high filtration efficiency of 99.96% for particles of 0.30 μm, a low pressure drop of 54 Pa and a satisfactory quality factor value of 0.1449 Pa at an airflow velocity of 5.3 cm/s. In particular, the composite filter exhibited better electret stability and PM loading performance than the commercial ones, which guarantees its long-term storage and usage.
空气中的悬浮颗粒物（PM）污染既对全球气候又对公众健康造成了严重影响。因此，高效节能空气过滤器的研发迫在眉睫。优化孔隙结构和增强驻极体是提高其过滤性能的可行手段。本文设计并制备了一种具有低压降和稳健过滤稳定性的新型三明治结构驻极体复合滤料。该复合滤料由具有大电阻率和高孔隙率的蓬松 PS 微纤维和具有高极性和小孔径的 PAN 纳米纤维组成。得益于在适当湿度下静电纺丝形成的蓬松结构、微纤维和纳米纤维适当混合形成的曲折孔隙通道以及由极性和非极性聚合物材料混合产生的丰富静电荷，PS/PAN/PS 复合滤料对 0.30μm 粒径的颗粒物的过滤效率高达 99.96%，压降仅为 54Pa，在 5.3cm/s 的气流速度下的质量因子值为 0.1449Pa。特别地，与商业滤料相比，该复合滤料具有更好的驻极体稳定性和 PM 负载性能，这保证了其长期储存和使用。
