KNOXVILLE, Tenn. — A University of Tennessee study is improving a widely used but poorly understood process used to make dust masks, air cleaners and filter products.
Dr. Randy Bresee, a UT-Knoxville Textiles Science professor, is using high-speed lasers and digital photography to uncover fundamental secrets about meltblown fabric manufacturing.
The project, supported by the Exxon Chemical Co., could demystify the complex process, resulting in more efficient manufacturing and better, cheaper filter products, Bresee said.
“Meltblowing is a fast, chaotic, complicated process,” Bresee said. “We don’t really understand how it works.
“Now, for the first time, we are able to look at the basic elements and gain a basic understanding of why we get different webs by changing meltblown production parameters.”
In the meltblown process, a plastic-like material called polymers are melted and sprayed onto a moving surface, creating a web of microscopic fibers ideal for fine-meshed filters.
Air pressure, surface speed, temperature, distance between the sprayer and collector, and other factors determine the properties of the fibers.
Predicting these variables has been a “hit-or-miss” proposition, Bresee said, but the UT images provide a better understanding of how they interact to form specific fabric characteristics.
“In the past, we could only change polymers, tweak the controls, and measure web properties at the other end,” Bresee said. “We knew that turning up air pressure changed the fiber, but we didn’t know why. Once we understand the process, it can be improved to make things faster, better and cheaper.”
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