CLEVELAND A recent discovery at Case Western Reserve University may help keep food and drugs safer and fresher longer and electronic equipment dryer and more secure than ever before all at a lower cost.
The finding involves a nanotechnology-based technique to block the transport of damaging gases through a polymer, making it stronger while using less material. It was made in the labs of the National Science Foundation-supported Center for Layered Polymeric Systems (CLiPS) at the Case School of Engineering. The findings are published in the Feb. 6, 2009, issue of the journal Science.
"This work takes a step toward developing more flexible, optically transparent, ultra-high barrier polymers for several different applications," said Anne Hiltner, lead author of the study and the Herbert Henry Dow Professor of Science and Engineering at Case Western Reserve. She also serves as lead investigator and co-director of CLiPS.
The discovery was a serendipitous find, according to Hiltner. The researchers found that when confined as nanolayers, polyethylene oxide (PEO) crystallizes as a single layer, resembling very large, impermeable single crystals that reduce by 100 times the amount of gas permeability in all kinds of polymer-based applications. When a crystallizable polymer is confined to such thin layers, it surprised the researchers by spontaneously organizing themselves into a nearly perfect crystalline packing of the polymer chains in each thin layer, Hiltner says.
Crystalline regions of polymers are areas where the atoms in polymer chains line up relative to one another in a rigorous and well-defined, ordered pattern, much like water molecules align next to each other in a well-defined pattern in ice (which is, in fact, crystalline water). Because the atoms are closely aligned to each other in a regular pattern, crystalline regions of polymers do not permit the transport through them of even the smallest gas molecules, s
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Case Western Reserve University