Russian scientists have proposed a simple method for the preparation of raw materials for the manufacture of conductive polymers. Researchers at the Novosibirsk Institute of Chemistry of Solid State Russian Academy of Sciences discovered that the addition of a saturated aqueous solution of urea alcohol molecules tend to form fibers. Upon heating of the mixture can be obtained an organic semiconductor — polyacetylene. The results of the work were published in the journal "Solid State Physics".
Conductive polymers have a number of unique advantages over conventional conductors and semiconductors. They combine the ability to conduct electrical current with typical mechanical properties of plastics. Moreover, they are often cheaper production. One of the most promising applications of conductive polymers — the creation of flexible displays.
Normally, the polymer molecules resemble a tangle of threads and do not conduct electricity. To transfer electrons between molecules is more efficient, it is necessary to achieve formation of intermolecular aggregates of polymer chains straightened. The research team, led by Boris Bohonovym offered the use of a saturated aqueous solution of urea (diamide of carbonic acid) — a cheap and widely used chemical compound.
Scientists mixed saturated aqueous solution of urea with a 10 percent solution of polyvinyl alcohol (PVA) and a few days the mixture was heated at room temperature. In solution formed fibers that reached one centimeter.
Effect of urea to form ordered structures investigated by means of transmission electron microscopy. In a solution containing less wetted mesh PVA — substrate for the polymeric material. Then urea molecules removed from the surface of the sample, and the mesh, coated PVA were placed in a electron microscope. On the pictures are clearly visible characteristic bands, traces of filamentous structures.
The interaction of molecules of urea and alcohol was also confirmed by means of infrared spectroscopy and Raman spectroscopy. Apparently, the urea molecule when added to a solution of PVK contribute to the formation of specific filamentous aggregates themselves and fill the cavity between them. After drying material scientists propose to use for the synthesis of organic semiconductor fibers — polyacetylene.
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