In one form the hybrid material is an ion conductor (an ion is an electrically charged atom), with great promise as highly efficient battery electrolytes. It is transparent and bendable but with considerable strength, and unlike pure ceramic will not shatter. Thus far the Cornell researchers have made only small pieces of the flexible ceramic, weighing a few grams, in petri dishes, but that is enough to test the material's properties. "The resulting material has properties that are not just the simple sum of polymers plus ceramic, but maybe something quite new," says Wiesner. ![]() If the polymer could somehow be melded with an inorganic material - a ceramic, specifically a silica-type material - the resulting hybrid would have a combination of properties: flexibility and structure control from the polymer and functionality from the ceramic. Nature's key to this replication, says Wiesner, "is perfect shape control governed by self-assembly of organic components directing inorganic materials' growth." The Cornell researcher reasoned that the simplest way to mimic nature's pathways was to use organic (or carbon-based) polymers - more particularly materials known as diblock copolymers - that have the ability to self-assemble chemically into nanostructures with different symmetries. An often-cited example is the elegant structure of diatoms, unicellular algae whose shell walls are made of perfectly replicated silica pores. Wiesner's research group was attracted to chemistry on the nanoscale (a nanometer is equal to the width of three silicon atoms) by the perfect, symmetrical shapes that are found in nature. In a talk, "Phase behavior of block copolymer directed nanostructured organic/inorganic hybrids," Wiesner will report that the material "is an exciting, emerging research area offering enormous scientific and technological promise." Wiesner reports on the new flexible ceramics today (8 a.m.) at the annual March meeting of the American Physical Society at the Indiana Convention Center, Indianapolis. The structure of the new material appears so convoluted that it has been dubbed "the plumber's nightmare." "We in polymer research are now finding structures that mathematicians theorized long ago should exist," says Ulrich Wiesner, associate professor of materials science and engineering at Cornell. ![]() What is particularly striking, even to the researchers themselves, is that under the transmission electron microscope (TEM) the molecular structure of the new material - known as a cubic bicontinuous structure - conforms to century-old mathematical predictions. The new materials appear to have wide applications, from microelectronics to separating macromolecules, such as proteins. Using nanoscale chemistry, researchers at Cornell University have developed a new class of hybrid materials that they describe as flexible ceramics.
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