COVID 19 - Superhydrophobic Microfiber Outer Layer for Facemasks to Decrease the Airborne Transmission of Human Pathogens

本项目提出将口罩外层由亲水性（呼吸性气溶胶/液滴粘附）改造为疏水性（排斥呼吸性气溶胶/液滴），以显著提高口罩的使用寿命。目前N95级（和非N95级）口罩短缺的主要原因是口罩的使用寿命短。蒙版通常有3层。两个外层具有微孔结构，可过滤大于1 μ m的气溶胶/液滴，同时提供保持口罩适当几何形状所需的机械强度。大多数口罩的外层是亲水的，因此大的呼吸道气溶胶/液滴通常会粘附在外层的表面。这些残留在口罩外表面的呼吸道气溶胶/飞沫可能是污染源，通常会缩短口罩的使用寿命。该项目建议通过赋予口罩表面超疏水性来克服这一缺陷，以排斥任何大于1 μ m的呼吸道气溶胶/液滴。这样，口罩可以长时间保持清洁。

This project proposes to cost-effectively modify mask outer layers from hydrophilic (to which respiratory aerosols/droplets adhere) to hydrophobic (repelling respiratory aerosols/droplets), to increase the lifespan of the masks dramatically. The current shortage of the N95 grade (and non-N95 grade) masks mainly comes from the short lifespan of the masks. Masks typically have 3 layers. The two outer layers have a microporous structure that filters aerosols/droplets greater than 1 µm, while providing the mechanical strength required for maintaining the proper geometry of the mask. The outer layers of most masks are hydrophilic, and therefore large respiratory aerosols/droplets typically stick to the surface of the outer layers. These respiratory aerosols/droplets remaining on the outer surface of the masks can be a contaminating source and often decrease the lifespan of the masks. This project proposes to overcome this deficiency by imparting a superhydrophobic nature to the mask surface to repel any respiratory aerosols/droplets larger than 1 µm. In this way, the mask can stay clean for a longer period. Since time is of the essence in the current situation, the development of an implementable technology will be prioritized over relevant fundamental research in this project. In addition to the lab-scale investigation, the small-scale-verified technology will be further tested on a pilot-scale spunbond system. This would substantially speed up the technology transfer to the industry (Myant Inc.), which is critically important at this moment because Canada is in acute demand for reliable facemasks due to the COVID-19 pandemic.