Electrooxidation of undiluted organic liquids swelling N-isopropylacrylamide-based copolymers

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• 作者：E. Bak ; J. Romiszewski ; M. Donten and Z. Stojek
• 关键词：Undiluted redox liquids ; Poly(N ; isopropylacrylamide) gels ; Voltammetry ; Blocking coefficient
• 刊名：Journal of Solid State Electrochemistry
• 出版年：2004
• 出版时间：September 2004
• 年：2004
• 卷：8
• 期：10
• 页码：861-867
• 全文大小：285 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Physical Chemistry
  Analytical Chemistry
  Industrial Chemistry and Chemical Engineering
  Characterization and Evaluation Materials
  Condensed Matter
  Electronic and Computer Engineering
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1433-0768

文摘

Polyacrylate gels such as: N-isopropylacrylamide (NIPA), ionic copolymer NIPA-co-sodium acrylate (NIPA-co-SA) and ionic copolymer NIPA-co-[2-(acryloyloxy)ethyl]trimethylammonium chloride (NIPA-co-XCl) were swollen by methanol, ethanol and N,N-dimethylformamide. These solvents were oxidized voltammetrically in the gels at platinum microelectrodes. The blocking coefficients, defined as the ratio of the currents observed in the presence and absence of the polymeric chains, were different for the solvents in the charged and uncharged polymers and did not differ for the electroactive probe, ferrocene, present in the solvents at millimolar level. This may mean that the micro ionic layer that is formed at microelectrodes at the plateau of the voltammetric solvent waves leads to a kind of collapse/phase transition of the polymer in the depletion layer. For methanol, the gel structure was found to prevent occasionally the formation of large gas bubbles at the potentials positive versus the first wave and then three one-electron waves could be obtained. Experiments done with a capillary cell and an optical microscope indicated that before formation of large bubbles at the Pt microelectrode a very dynamic, dense stream of microbubbles leaves the electrode surface.