Microplastic pollution, known as "pm2.5 in water", has become a direct source of pollution in the ocean, soil and drinking water, affecting human health. Medical protective coveralls is almost made of different polymer materials. The development of a new material can replace the existing material to form a new series of products. As most of the existing protective suits are designed to be disposable, they are used heavily during the pandemic. Used medical protective clothing should be disposed of centrally to prevent secondary transmission of the virus. Therefore, protective clothing materials must be developed to be repeatable and degradable.
Due to the particularity of application scenarios, most medical protective gown is disposable. Therefore, environment-friendly materials should be considered in the development of medical protective gown, and must be considered before material selection and protective clothes design. In 2009, NatureWorks developed two new low carbon IngeoTM products for melt-blown nonwovens, which have greatly contributed to the green development of disposable protective gown. Some bio-based fibers can be prepared as inner layer protective materials, such as chitosan fiber, polylactic acid fiber, sodium alginate fiber, etc. The use of disposable medical protective clothing during the epidemic has resulted in a large amount of medical waste, Compared with the American AAMI PB70 ∶ 2012 and NFPA1999 ∶ 2008 and the European EN 13795 ∶ 2011+ a1:2013 and EN 14126 ∶ 2003 standards, the scope of application includes disposable and durable types. In addition to the green, degradable and repeatable use of raw materials, the quantification of carbon emissions can also play an important role in the environmental protection of disposable products. The quantification of carbon footprint of medical protective cloth can quickly improve its environmental protection.
The safety of medical protective clothing usually starts from two aspects: refinement of fiber diameter and superhydrophobicity of material surface. In general, the diameter of viruses is usually between 30 and 300 nm. Only when the product developer knows the diameters of various viruses can he properly configure the fibre diameters or apertures required for the materials related to medical protective clothing. The study found that the fiber diameter should be less than 0.45 μm to meet the REQUIREMENTS of AAMI Class 4 protection. In addition to the membrane, among the commonly used medical protective clothing materials, melt-blown nonwoven materials with the smallest fiber diameter can only achieve 1-4 μm, failing to pass the virus and blood permeability tests. Therefore, Some researchers tried to form a film on the surface of melt-blown materials through plasma treatment and chemical treatment to improve its filtration, permeability and liquid repellent properties. Nano fiber materials can solve this problem well. In nano fiber wikis medical protective clothing, self-antibacterial properties can be obtained by using nano zinc oxide, but there is still a certain distance to large-scale industrial production of nano fiber materials. In this case, once the nanofiber industrialization is realized, melt-blown layer can be replaced as the isolation layer to obtain more efficient protection, which will greatly improve the protective performance of medical protective clothing. Viruses are often attached to liquid materials, and the superhydrophobicity of the surface of the material can significantly reduce the adsorbability of the virus carrier and effectively hinder the spread and diffusion of the virus. Some scholars modified PTFE coating by SiO2 and PTFE to prepare superhydrophobic fabric, and obtained superhydrophobic surface by organosilicon and epoxy resin. The similarities between the two are acid and alkaline, thermal stability and mechanical external force stability test. At present, good results have been achieved in both aspects. However, how to achieve superhydrophobicity without reducing the air permeability and moisture permeability is a difficulty in the research, which is also an important threshold affecting the market application of repeatable medical protective coveralls.
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