It can be washed with water, sterilized with alcohol and used for many times
This kn95 mask was born in the new area!
Since novel coronavirus pneumonia grow with each passing day, the demand for mask has been increasing. More than 3000 enterprises in the country have added masks. As the key material of mask filtration, the melt blown cloth with the diameter of only one thirtieth of hair can be called the "heart" of medical surgical mask and kn95 mask. The supply is very tight, which can be said to be "one cloth is hard to find".
In order to alleviate the shortage of melt blown cloth in the current market, the membrane science and Technology Research Institute of Nanjing University of technology gave full play to its professional advantages, developed a new type of filter material - Nano arachnoid bionic membrane, and applied it to the production of high-performance membrane mask, taking on the mission of "epidemic" with the membrane technology achievements.
No need to add static electricity, high filtering efficiency
The diameter of nano arachnoid biomimetic membrane fiber is in the range of 100-200nm, and the fibers are staggered with each other to form a three-dimensional arachnoid structure, and the size of the micropores can be controlled within the range of 0.1-0.5 μ M. "Compared with the melt blown materials with disordered fiber stacking and a diameter of more than 1000 nm, the nano arachnoid biomimetic membrane has the advantages of high porosity, small pore diameter, low filtration resistance and high filtration accuracy." Introduction of Professor Zhong Zhaoxiang, Department of membrane science, Nanjing University of technology.
Generally, there are a large number of fine particles with positive and negative charges in the air. When these charged particles in the air pass through the vicinity of the electret, they will be strongly adsorbed on the electret fiber. Meanwhile, the uncharged particles will be polarized by induction in the electric field formed by the electret, and will also be adsorbed on the fiber. The traditional melt blown material has a large aperture, so it needs to add static electricity to improve the filtration efficiency. However, the static electricity is affected by the temperature and humidity in the environment, and it will fail in a short time, so the filtration efficiency is rapidly reduced, so the medical mask produced by the traditional melt blown cloth can only be used once in the market.
Professor Zhong Zhaoxiang introduced
Because of its high porosity, small pore size, low filtration resistance and high filtration accuracy, nano arachnoid biomimetic membrane material can effectively filter more than 99% of non oily particles, effectively intercept various solid aerosols, droplets and viruses through screening, without worrying about the problem of low filtration efficiency of liquid, and has good air permeability The discomfort of breathing.
It can be washed with water and sterilized with alcohol, with long service life
At present, most of the medical surgical masks on the market are disposable, with a maximum use time of four hours. Although kn95 masks have a longer use time, they cannot be used repeatedly for a long time. This is because once the melt blown material adsorbs pollutants by charging, it is easy to have static neutralization phenomenon when encountering water, which will reduce the filtering efficiency of the mask, so the mask produced by melt blown cloth cannot be reused after ordinary cleaning.
Professor Zhong Zhaoxiang's doctoral students
Introduction of Wu Junwei
Nano arachnoid biomimetic membrane materials have small pore size, and they mainly intercept pollutants through physical action, so there is no need to worry about the reduction of liquid efficiency.
Our team's researchers soaked the membrane materials in water and 75% alcohol for many times, and the filtration efficiency was not affected, both of which were kept above 99%, indicating that the membrane materials mask can be washed with water or sterilized with alcohol and reused, which greatly increased the utilization rate of the mask.
Wu Junwei said
Compared with the traditional melt blown materials, the nano arachnoid bionic membrane material, as a new filter material, has more excellent retention and air permeability, so it can be reused and has a longer life.
Make masks, medical protective clothing, etc., with a wide range of applications
According to reports, the nano arachnoid biomimetic membrane material developed by the membrane Department of Nanjing University of technology can be used not only for making masks, but also for medical protective clothing, air purifier and other fields.
Zhong Zhaoxiang said
The protective clothing based on nano arachnoid biomimetic membrane material has good antibacterial and water repellent performance, which is the highest level of medical protective clothing. It is characterized by that the sweat gas of human body can be sent out, while the outside water, bacteria and viruses can not enter. "The nano arachnoid biomimetic membrane material has about 1 billion pores per square centimeter, with porosity of more than 90%. The pore diameter is about 0.2 μ m, which is one thousandth of the diameter of the water drop, but it is about 700 times larger than the size of the water vapor molecule. The liquid water can not enter, and the sweat gas can be penetrated, so it can achieve excellent water and moisture permeability."
In the industrial field, through the application of double sparse modified air purification membrane for ultra-low emission control of smoke and dust, hundreds of engineering equipment have been promoted and applied, with economic benefits of more than 2 billion yuan. It has successively won the first prize of technology invention of China Petroleum and Chemical Industry Federation, the first prize of science and technology of China Film Industry Association, the youth prize of chemical science and technology of Hou Debang, etc.
At present, air purification membrane materials and membrane masks have been used in hundreds of units, providing a strong guarantee for the staff who adhere to the front line of epidemic prevention. Recently, the membrane Department of Nanjing University of technology has also received thank-you letters from domestic and foreign organizations, such as Nanjing Pukou Charity Federation, Italian National Research Institute, American filtration and separation Association, for donating materials of membrane technology anti epidemic masks. At the theme meeting of epidemic prevention materials held by Nanjing municipal government, the air purification membrane technology was highly valued by Nanjing Municipal Bureau of industry and information technology, science and Technology Bureau and other departments, helping to contact and implement many enterprises to carry out the production docking of air purification membrane masks, and making due contributions to the victory of the epidemic.
Source: Jiangbei new area, Nanjing
The following information deserves attention