Polymer electrolyte resonance spectroscopy

Magnetic Resonance Imaging and Tunable Diode Laser Absorption Spectroscopy for In-Situ Water Diagnostics in Polymer Electrolyte Membrane Fuel Cells... 

This review deals with several types of polymer hosts that have been investigated. These include polyethylene oxide and its several modified forms, comb like polymers such as polyacrylates and inorganic polymers such as polyphosphazenes and polysiloxanes. Various instrumental techniques have been employed in the structural characterization of polymer electrolytes. The structural information obtained from methods such as Extended X-ray Absorption Fine Structure (EXAFS), X-ray diffraction methods, vibrational spectroscopy and nuclear magnetic resonance (NMR) have also been discussed. 

R83 S. Abbrent and S. Greenbaum, Using Nuclear Magnetic Resonance Spectroscopy in Polymer Electrolyte Research , in Polymer Electrolytes Fundamentals and Applications, eds. C. Sequeira and D. Santos, Woodhead Publishing Ltd., Cambridge, UK, 2010, p. 278. 

NMR spectroscopy has also been used extensively to study various electrolytes. Challenges and strategies for successful electrolytes have been previously described in literature [1, 17, 79, 80]. In a few instances, these materials consist of solid polymers [17], which are typically of high molecular weight or cross-linked, gel electrolytes, or composite materials containing additives [81-85]. In recent years, nanoscopic additives have gained recent attention [86-88]. A significant contribution of NMR spectroscopy to the polymer electrolyte community arose from line-width measurements of various resonances as a function of temperature [89-92]. The results showed a correlation between ionic conduction... 

Jing, F., Hou, M., Shi, W, Fu, J., Yu, H., Ming, P. and Yi, B. (2007) The effect of ambient contamination on PEMFC performance. J. Power Sources 166, 172-176 Kadirov, M. K., Bosnjakovic, A. and Schlick, S. (2005) Membrane-derived fluorinated radiceds detected by electron spin resonance in UV-irradiated Nafion and Dow ionomers Effect of counterions and H O - J- Phys. Chem. B 109, 7664-7670 Kelly, M. J., Egger, B., Fafilek, G., Besenhard, J. O., Kronberger, H. and Nauer, G. E. (2005a) Conductivity of polymer electrolyte membranes by impedance spectroscopy with microelectrodes. Solid State Ionics 176, 2111-2114... 

In 1968/1969 DaH Olio et al. in Parma, Italy, revitalized polypyrrole chemistry by oxidizing pyrrole itself electrolytically to pyrrole black ("noir d oxypyrrol")/° In contrast to the investigations of Weiss et al., Dall Olio and his coauthors focused on the electrochemical behavior of pyrrole and its electropolymerization. The paramagnetic behavior of the polymer was studied (the g-factor of the free radical was measured to 2.0026 by electron spin resonance spectroscopy), and a remarkable electric conductivity of 7.54 S/cm at ambient temperature was foimd. 

Among the polymer electrolytes obtained from natural polymers, Klink-lai et reported ionic conductivity and NMR spectroscopy of polymer electrolytes formed by the mixture of liquid epoxidized natural rubber with Uthium salts. The authors discussed the correlation between the spin-lattice relaxation times with the solubility of the different lithium salts in the deprotonized liquid rubber. Based on the NMR chemical shift and the resonance half-width and the spin-lattice relaxation times results they concluded that lithium bis(trifiuoro methane sulfonyl)imide is a suitable salt for forming polymer electrolytes with deprotonized liquid natural rubber. 

Using nuclear magnetic resonance spectroscopy in polymer electrolyte research... 

The latexes were cleaned by ion exchange and serum replacement, and the number and type of surface groups were determined by conductometric titration. The molecular weight distributions of the polymers were determined by gel permeation chromatography. The stability of the latexes to added electrolyte was determined by spectrophotometry. The compositional distribution was determined by dynamic mechanical spectroscopy (Rheovibron) and differential scanning calorimetry, and the sequence distribution by C13 nuclear magnetic resonance. 

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