The role of polymer materials in the battle against novel coronavirus

At present, the people of the whole country are mobilized to fight against novel coronavirus with one heart and one mind, and it is in a critical period. We believe that by strengthening confidence and taking proper measures, we will definitely win the national campaign against novel coronavirus.

In this campaign, we saw that polymer materials played a very big role.

I. Medical masks and disposable protective clothing

image.png

Medical masks are mainly made of non-woven fabrics made of polymer materials, taking the common medical masks as an example. Medical masks are generally multi-layered, generally referred to as SMS structure, as shown in Figure 1 and Figure 2.

In the national standard GB/T 32610, medical masks should have at least three layers, that is, SMS (two layers of S and one layer of M). At present, the highest layer in China is five layers, that is, SMMMS (two layers of S and three layers of M).

Here, S stands for Spunbond, and its fiber diameter is relatively thick, about 20 microns (μm). The main function of the two-layer S spunbonded layer is to support the whole nonwoven structure, but it has little effect on the barrier. The most important thing in the mask is the barrier layer or melt blown layer M(Meltblown). The fiber diameter of the melt blown layer is relatively thin, about 2 microns (μm), so it is only one tenth of the diameter of the spunbonded layer, which plays a vital role in preventing bacteria and blood from permeating it. If there are too many S spunbond layers, the mask will be hard, while if there are too many M meltblown layers, 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 will be. However, if the M layer becomes a film, it will basically be impossible to breathe, and the virus will be blocked and people will soon die. Therefore, this is also a technical problem.

At present, these non-woven fabrics are mainly made of polypropylene, a common polymer material. Of course, different layers have different requirements for polypropylene. For example, M-layer requires good fluidity and requires the use of high melt index polypropylene. S layer requires high strength. In China, there are not many polypropylene with high melt index, and the technology is not too strong.

In addition, disposable protective clothing is also made of non-woven fabric, which is similar to the non-woven fabric material of medical masks.

Second, the protective eyepiece and mask

In the case of high protection level, protective eyepieces and masks are needed.

In our understanding, lenses? They may be glass. But in fact, almost all lenses, including glasses lenses, are made of polymer materials. The most common ones are PC, PMMA, etc. Polymer lenses are not only light and fragile, but also easy to form, with high efficiency, and can be made into special-shaped structures.

Three, infusion, injection supplies

At present, almost all disposable infusion sets and injection needles we use are made of polymer materials. Infusion tubes used to be mainly made of PVC, but now a considerable part of them are made of TPE.

In addition, the injection needle tubes are used in large quantities, mainly PVC and polypropylene.

Fourth, drug packaging

There are many kinds of materials used in drug packaging, because drugs are solid, liquid, tablets, powder, etc., so some use bottles, bottles and cans, some use films, and there are many polymer materials involved, including PVC, PP, PC, PA and so on.

Five, medical prefabricated room materials

In order to quickly cope with the development of the epidemic, specialized hospitals such as Vulcan Mountain and Raytheon Mountain will be built within a few days. According to the conventional method, it is difficult to satisfy with conventional materials. When these two hospitals were built, the technology of quick mobile home was used.

This modular house uses a lot of polymer materials.

In addition, there are various water supply and drainage systems, communication systems, etc. .......

With the development of polymer materials, great general materials and great engineering plastics have been formed for different applications, and special materials have been applied in some special fields. It can be said that our daily necessities are inseparable from polymers. In this battle against novel coronavirus, polymer materials also play a very important role!