At present, people across the country are mobilized and united to fight against the pneumonia epidemic caused by the new coronavirus infection, and we are in a critical period. We believe that as long as we increase confidence and take appropriate measures, we will win this national battle against the epidemic.
In this battle, we saw that polymer materials played a very important role.
1. Medical masks and disposable protective clothing
Medical masks are mainly made of non-woven fabrics made of polymer materials. 5. Take masks as an example: Medical masks are generally multi-layer structures, generally referred to as SMS structures. The schematic diagrams are shown in Figures 1 and 2.
In the national standard GB/T 32610, medical masks should be at least 3 layers, which is what we call SMS (2 layers S layer and 1 layer M layer). At present, domestic The highest number of layers is 5, which is SMMMS (2 layers S layer and 3 layers M layer).
The S here represents the spunbond layer (Spunbond). The fiber diameter is relatively thick, about 20 microns (μm). The main function of the two layers of S spunbond layer is to support the entire The non-woven structure does not have much effect on barrier. The most important thing in the mask is the barrier layer or meltblown layer M (Meltblown). The fiber diameter of the meltblown layer is relatively thin, about 2 microns (μm), so it is only one-tenth the diameter of the spunbond layer. This is good for preventing bacteria. , blood penetration plays a vital role. If there are too many S spunbond layers, the mask will be harder, and if there are too many meltblown layers M, it will be difficult to breathe. Therefore, the isolation effect of the mask can be judged from the difficulty of breathing. The more difficult it is to breathe, the better the isolation effect. , However, if the M layer becomes a thin film, it will basically be impossible to breathe. The virus will be blocked and the person will soon die. Therefore, this is also a technical problem.
At present, these non-woven materials are mainly made of polypropylene, a common polymer material. Of course, different layers have different requirements for polypropylene. For example, the M layer requires good fluidity and needs to use high melt index polypropylene. The S layer requires high strength. In my country, there are not many polypropylene products with high melting index, and the technology is not very strong.
In addition, disposable protective clothing is also made of non-woven fabrics, and the requirements are similar to the non-woven materials of medical masks.
2. Protective goggles and masks
In cases where the level of protection is relatively high, protective goggles and masks are required.
From our understanding, the lenses may be made of glass. But in fact, almost all lenses now, including spectacle lenses, are made of polymer materials. The most common ones are PC, PMMA, etc. Polymer material lenses are not only light and not fragile, but also easy to form, highly efficient, and can be made into special-shaped structures.
3. Infusion and injection molding supplies
At present, almost all of the disposable infusion sets and injection molding needles we use are made of polymer materials. Infusion tubes used to be mainly made of PVC materials, but now a considerable part of them are made of TPE materials.
In addition, injection needles are used in large quantities, mainly PVC and polypropylene.
4. Pharmaceutical packaging
There are many types of materials used in pharmaceutical packaging. Because pharmaceuticals include solids, liquids, tablets, powders, etc., some use bottles. Bottles and cans, some use membranes, and there are many polymer materials involved, including PVC, PP, PC, PA, etc.
5. Materials for medical prefabricated houses
In order to quickly respond to the development of the epidemic, Huoshenshan, Leishenshan, etc. must be built within a few days. Specialty hospital. According to conventional methods, it is difficult to satisfy with conventional materials. These two hospitals used rapid mobile room technology when they were built.
This kind of modular house uses a large amount of polymer materials.
In addition, there are various water supply and drainage systems, communication systems, etc…
The development of polymer materials has formed an extremely large number of applications in different fields. Most general materials, as well as engineering plastics, and special materials used in some special fields. It can be said that our current basic necessities of life are inseparable from polymer materials. In this battle against pneumonia caused by the new coronavirus infection, polymer materials also play a very important role! </p