After visiting China and enduring the stifling air pollution, Stanford engineering professor Yi Cui, PhD, wanted to explore solutions to the problem. This week, his team published a paper in the scientific journal Nature Communications, detailing a new kind of highly effective air filter made out of polyacrylonitrile, a synthetic polymer that is used to make surgical gloves.
The researchers used a relatively new technique called electrospinning, or drawing out microscopically thin threads from a liquid to make a lightweight and fairly transparent filter out of PAN. The filter attracts particles from the air, especially those around 2.5 microns - or PM2.5 - which are among the most dangerous for the human respiratory tract.
The researchers make the case for the new PAN air filter pretty eloquently in a press release:
"It was mostly by luck, but we found that PAN had the characteristics we were looking for, and it is breathtakingly strong," said Po-Chun Hsu, co-author on the study and a graduate student in Cui's lab.
. . .
"The fiber just keeps accumulating particles, and can collect 10 times its own weight," said Chong Liu, lead author on the paper and a graduate student in Cui's lab. "The lifespan of its effectiveness depends on application, but in its current form, our tests suggest it collects particles for probably a week."
The material collects 99 percent of air particles for up to a week, but is still 70 percent transparent, so it could be used as a window covering. "It might be the first time in years that people in Beijing can open their window and let in a fresh breeze," Cui said in the statement.
Previously: The high cost of pollution on kids' health, Study shows air pollution may increase heart attack risk more than drug use, Continuing pollution restrictions used during Beijing Olympics could reduce cancer rates and New insight into asthma-air pollution link
Video by Kurt Hickman