Foam test could help inspectors monitor labs for banned weapons

New Clemson University technology close to ready, professor says

New technology under development at Clemson University could help inspectors determine whether nations have violated international treaties by allowing work with chemicals that are used in banned weapons.

Igor Luzinov, a materials science and engineering professor, calls the technology an  “unattended off-line sensing system” and said it could be completed in two years.

An extremely thin polymer foam is attached to a silicon chip measuring about one-inch-by-one-inch. It would be placed in labs and collected about once a month, he said.

The foam would collapse at specific points if it had been exposed to chemicals that could be used in banned weapons, Luzinov said.

The foam would be chemically encrypted to make it impossible to replicate without highly specific inside intelligence, he said. Any tampering would be obvious to scientists, Luzinov said.

“It’s virtually foolproof,” he said.

 

 

Luzinov said his team has proven the technology works and is now perfecting it. The foam so far has been exposed to high concentrations of vapors and needs to be made more sensitive, he said.

His work has been funded with about $1.4 million from the Defense Threat Reduction Agency. He has been collaborating with Lionel Kimerling and Anu Agarwal of the Massachusetts Institute of Technology; Kathleen Richardson of the University of Central Florida; and Joel Hensley of Physical Sciences, Inc.

Tanju Karanfil, associate dean for research and graduate studies in the College of Engineering and Science, called Luzinov an impeccable researcher whose work is on the cutting edge of materials science and engineering.

“Dr. Luzinov’s exemplary work is addressing the complex challenges facing the global community,” Karanfil said. “His research into polymers is a game-changer.”

Researchers start with a silicon chip as a base. Then they graft an extremely thin polymer film onto the chip.

The film is infused with a solvent that swells it, and the foam is formed as the solvent turns from vapor to solid. It can be made so that every point on the foam has different chemical composition.

The foam’s topography is later measured with precision lab equipment, such as an ellipsometer. Researchers can also put the foam on “optical micro-resonator arrays” that have been developed at the partner institutions for precise detection, Luzinov said.

“We can get a very accurate profile,” he said.

Researchers published some of their findings earlier this year in a paper published by the Royal Society of Chemistry. The paper was titled “Temperature controlled shape change of grafted nanofoams.”

Luzinov said he has been developing new ways of attaching polymers to surfaces for a decade and that the foam works because of the prior research.

“When it swells, it does not dissolve and it stays in place during operation,” he said.

Luzinov is also using his research to make biodegradable plastics and new coatings for fibers and textiles. But he said the foam test for treaty verification is what currently excites him most.

“It’s a very simple device, but it’s based on fundamental polymer science and knowing how polymer materials behave,” Luzinov said.