Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

VCU engineers develop new polymer

03.05.2005


New coating becomes water repellant when wet; applications include medical diagnostic equipment



Virginia Commonwealth University chemical engineering team has developed a novel material that becomes water repellent when wet, setting the stage for advances in engineering, medicine and diagnostics.

In the April 26, 2005, issue of the journal Langmuir, a publication of the American Chemical Society, Kenneth J. Wynne, Ph.D., a professor in the VCU School of Engineering’s Department of Chemical Engineering, and Umit Makal, a graduate student at VCU, created a enigmatic polymer that is hydrophilic, or water loving, when dry, and hydrophobic, or water resistant, when wet; opposite of most materials.


Makal drew an analogy of the research to a drop of water in a Teflon-coated pan. "Water in such a pan just rolls off," he said. "On our surface, when the pan is dry, water just loves the surface … it tries to stick to the surface."

"This discovery runs counter to intuition," Wynne said. "Water-induced hydrophobic surfaces may lead to applications for many things, including the testing of bodily fluids, switching devices, drag-reducing coatings and many others.

"Sometimes an engineer wants to guide the flow, or turn off tiny streams of fluid, such as blood, in a test tube, and this kind of phenomenon could be useful in creating channels for that purpose."

Wynne and Makal actually were working to create antimicrobial coatings by incorporating a molecule called hydantoin into fluorine-containing polymer chains. Makal was testing the behavior of water on one of these coatings and observed that the water drops were spreading, wetting the surface.

"After we took the drop off and put it back again, it started hating the water," Makal said. "The surface became water repellent where the original drop of water had been."

Wynne and Makal concluded that the change was caused by a rearrangement of the polymer side chain, which exposed the hydrophobic, fluorine-containing groups to the surface and made them repel water.

"The process can be reversed by drying the surface," Wynne said.

Anne Buckley | EurekAlert!
Further information:
http://www.vcu.edu

More articles from Materials Sciences:

nachricht Novel sensors could enable smarter textiles
17.08.2018 | University of Delaware

nachricht Quantum material is promising 'ion conductor' for research, new technologies
17.08.2018 | Purdue University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: It’s All in the Mix: Jülich Researchers are Developing Fast-Charging Solid-State Batteries

There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.

The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Quantum bugs, meet your new swatter

20.08.2018 | Information Technology

A novel synthetic antibody enables conditional “protein knockdown” in vertebrates

20.08.2018 | Life Sciences

Metamolds: Molding a mold

20.08.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>