Scientists have devised a new technique for containing the spread of oil slicks which involves the creation of “virtual walls” that bar the movement of low surface tension liquids.

Scientists from the University of Missouri's College of Engineering have developed a new material which is capable of directly dealing with the low surface tension of oil, allowing for the more effective channeling and control of its movements.

Surface tension is the product of the cohesive propensity of similar molecules situated at the surface of a liquid, which permits the formation of structures that are capable of resisting external force.

This phenomenon leads to behaviour which many would instinctively consider to be contrary to the nature of matter in a liquid state - such as the formation of discrete dome-shaped droplets, or the ability of water to allow certain insects, such as water striders, to stroll across its surface without sinking.

Oil has a low surface tension, however, which makes it very slippery and highly difficult to control when its enters a body of water. This is why oil spills are so difficult for emergency workers to contain, making them especially hazardous to the environment.

The new material, developed by Professor Jae Kwon, an associate professor of electrical and computer engineering at MU's College of Engineering, and graduate student Riberet Almeida, possesses a strong oil repelling ability which is based upon the specific targeting of liquids that possess low-surface tension.

Jae Kwon

Jae Kwon, associate professor of electrical and computer engineering in the College of Engineering at MU

This leads to the formation of a "virtual wall" which bars the movement of such liquids, and could prove highly effective as a means of containing oil spills in future.

"Our newly developed surface helped keep oil, which is normally unmanageable, in predetermined pathways making it controllable," said Kwon in an official statement.

The new technique arose from efforts by Kwon and his colleagues to devise a means of controlling the impact of oil on miniaturized devices which are used by scientists for research purposes.

"Our work is based on micro/nanoelectromechanical systems, or M/NEMS, which can be thought of as miniaturized electrical or mechanical structures that allow researchers to conduct their work on the micro-nanoscopic level," said Kwon. "Oil-based materials or low-surface tension liquids, which can wet any surface and spread very easily, pose challenges to researchers who need to control those tiny oil droplets on microdevices."

Kwon said the new material could have a broad range of applications in addition to its immense promise as a means of curbing the catastrophic damage caused by oil spills.

"We feel that oil-repellant surfaces can be widely utilized for many industrial applications, and virtual walls for low-surface tension liquids also have immense potential for many lab-on-a-chip devices which are crucial to current and future research technique," he said.