[Explanation] In 2020, the new crown pneumonia epidemic will sweep the world, and masks have become a necessity for people to fight the epidemic.

A few days ago, the Hong Kong University of Science and Technology announced the development of the world's strongest polymer nano-film, which can be used to make transparent masks with a filtering performance that exceeds N95 masks to facilitate communication among people with disabilities.

　　[Concurrent] Gao Ping, Professor, Department of Chemistry and Biological Engineering, Hong Kong University of Science and Technology

　　This is a mask that we made of nano-film. It has three characteristics. First, it is transparent.

Secondly, it is highly breathable. Look at my students wearing this mask.

The third most important thing is that its filtering performance is very good, that is, its filtering performance is more than N95 (mask). We use the world's most stringent standard, which is to add or subtract 20 nanometer particles to 75 nanometers. , Its filtering effect exceeds 99%.

　　[Explanation] Talking about the original intention of the research, Gao Ping, a professor in the Department of Chemistry and Bioengineering of the Hong Kong University of Science and Technology, introduced that she and the team had been committed to the research of polymer materials before.

The pandemic raging around the world this year gave her the idea of ​​developing a "transparent mask".

　　[Concurrent] Gao Ping, Professor, Department of Chemistry and Biological Engineering, Hong Kong University of Science and Technology

　　There are some people in society, such as deaf-mute people, who cannot hear them. Then, 65% of his communication is based on facial expressions. What he needs is to read your mouth shape.

Of course, there are some security considerations. For example, if you go to the bank or go through customs, then your mask will be taken off. Actually, when I saw a news from the BBC at the beginning of (2020), then it said In fact, everyone wants to have transparent masks now.

　　[Explanation] To make a medical-grade transparent mask, the three properties of "safety", "breathable" and "transparent" are indispensable, so the choice of materials is very important.

　　[Concurrent] Gao Ping, Professor, Department of Chemistry and Biological Engineering, Hong Kong University of Science and Technology

　　Many materials are now transparent, including glass, including the face shield we use now, which are all transparent materials.

But if you need it to be breathable, you need to have holes in it. After the holes are added, it becomes opaque. How do you make it transparent?

The thickness of your film, which is the thickness of the light propagation direction, must be lower than the wavelength of visible light, which is 400 to 700 nanometers.

Then only materials below 400 nanometers can ensure that the membrane is breathable, then porous, and then transparent at the same time. Then we thought of using our nano membrane, because our nano membrane (thickness) is made of hair Below one thousandth, that is far below the wavelength of visible light.

　　[Explanation] After months of hard work, Gao Pinghe's team finally made an original model and proved its antibacterial and breathable properties through multiple experiments.

　　[Concurrent] Gao Ping, Professor, Department of Chemistry and Biological Engineering, Hong Kong University of Science and Technology

　　What we saw above is a film about the same size as the iPad mini. In fact, this is composed of two films.

Here is the clean film (preservation film) we usually use in the kitchen, and here is our GP Nano film.

How do we show this difference in breathability?

If we put it in our fish tank, we can see that the bubbles will be collected on the clean film. It can't pass through, but the bubbles will pass quickly through our GP Nano.

　　[Explanation] Gao Ping introduced that although this film is light, thin, soft and breathable, it is 25 times stronger than stainless steel of the same quality and is waterproof.

She said that in the future, by adjusting the size of the pores, this nano-film can also be used in other cutting-edge technology products such as wound waterproof dressings, wearable devices, seawater desalination, and solar cells.

　　Reporter Fan Siyi and Li Yue from Hong Kong

Editor in charge: 【Luo Pan】