Zangmeister Christopher D, Radney James G, Staymates Matthew E, Vicenzi Edward P, Weaver Jamie L
Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
Museum Conservation Institute, Smithsonian Institution, Suitland, Maryland 20746, United States.
ACS Appl Nano Mater. 2021 Mar 26;4(3):2694-2701. doi: 10.1021/acsanm.0c03319. Epub 2021 Mar 8.
Under high humidity conditions that mimic respiration, the filtration efficiency (FE) of hydrophilic fabrics increases when challenged with hygroscopic nanoparticles, for example, respiratory droplets containing SARS-CoV-2. The FE and differential pressure (Δ) of natural, synthetic, and blended fabrics were measured as a function of relative humidity (RH) for particles with mobility diameters between 50 and 825 nm. Fabrics were equilibrated at 99% RH, mimicking conditions experienced when worn as a face mask. The FE increased after equilibration at 99% RH by a relative percentage of 33 ± 12% for fabrics composed of two layers of 100% cotton when challenged by 303 nm-mobility-diameter NaCl aerosol. The FE for samples of synthetics and polyester/cotton blends was unchanged upon equilibration at 99% RH. Increases in FE for 100% cotton fabrics were a function of particle size with a relative increase of 63% at the largest measured particle size (825 nm). The experimental results are consistent with increased particle capture due to HO uptake and growth as the particles traverse the fabric.
在模拟呼吸的高湿度条件下，当受到吸湿性纳米颗粒（例如含有SARS-CoV-2的呼吸道飞沫）挑战时，亲水性织物的过滤效率（FE）会提高。对于迁移直径在50至825纳米之间的颗粒，测量了天然、合成和混纺织物的FE和压差（Δ）与相对湿度（RH）的函数关系。织物在99%RH下平衡，模拟作为口罩佩戴时的条件。当受到303纳米迁移直径的NaCl气溶胶挑战时，由两层100%棉花组成的织物在99%RH下平衡后，FE相对增加了33±12%。合成纤维和聚酯/棉混纺织物样品在99%RH下平衡后，FE没有变化。100%棉织物的FE增加是颗粒大小的函数，在最大测量粒径（825纳米）时相对增加63%。实验结果与颗粒在穿过织物时由于HO吸收和生长导致颗粒捕获增加一致。
