This crystal, photographed with false color processing using a scanning electron microscope, is made up of sheets of polymers containing cracks and tears. Ralph Lange, a Ph.D. student at ETH Zurich, formed the sheets by crystallizing the monomers before polymerization. That allowed monomers to form covalent bonds with others within the same plane. To picture the result, “imagine looking at a closed book, where you see the edges of distinct pages from the side,” Lange explains. This crystal has been immersed in a solvent for some time, causing it to slowly disassemble into sheets. Lange and his coworkers envision using these sheets as nanoscale sieves for gas separation. The polymers have uniform pore sizes and are very thin, which they expect would make the sieves highly selective and permeable to gases.
Submitted by Ralph Lange
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