Nafion 1379, wide angle

Gierke, T. D., Munn, G. E. and Wilson, F. C. 1981. The morphology in Nafion perfluorinated membrane products, as determined by wide-angle and small-angle x-ray studies. Journal of Polymer Science Polymer Physics 19 1687-1704. 

Wide-Angle X-Ray Diffraction Studies. An interesting feature of the Nafion membranes is its ability to crystallize in spite of the long side-chain groups. The presence of crystallites in perfluorinated... 

Effect of Crystallinity. While neutralization is known to exert a strong influence on mechanical relaxations, it is conceivable that the degree of crystallinity is also significant. To explore this aspect, an amorphous Nafion salt sample was prepared by rapid quenching from the melt (40). The original Nafion salt (EW = 1200) had a degree of crystallinity of ca. 7% as revealed by a wide angle X-ray diffraction study (40). The quenched sample was also found to be completely amorphous by the absence of the crystalline diffraction peak. 

The structure of PEMs, in particular their phase-separated morphology at nm-scale, has been studied with a number of experimental techniques, including small- and wide-angle X-ray and neutron scattering, infrared and Raman spectra, time-dependent FTIR, NMR, electron microscopy, positron annihilation spectroscopy, scanning probe microscopy, and scanning electrochemical microscopy (SECM) (for a review of this literature see [31]). Structural studies of PEMs have mainly focused on Nafion. A thorough recent review on this particular membrane is provided in [32]. 

CrystalHnity in Nafion was probed by detailed wide-angle X-ray diffraction (WAXD) experiments [35]. A small degree of crystallinity (<12%) was found in sulfonated 1100 EW Nafion. 

HaUm, J., Scherer, G.G., and Stamm, M. (1994) Characterization of recast Nafion films by small- and wide-angle X-ray scattering, Macromol. Chem. Phys., 195, 3783-3788. 

T.D. Gierke, G.E. Munn and EC. Wilson, Morphology of Nafion perfluorosulfonated membrane products, as determined by wide- and small-angle X-ray studies, J. Polym. Sci., Polym. Phys. Ed., 1981, 19, 1687-1704 W.Y. Hsu and T.D. Gierke, Elastic theory for ionic clustering in perfluorinated ionomers, Macromolecules, 1982, 15, 101-105. 

Gierke TD, Munn GE, Wilson FC (1981) The mraphology in Nafion prulluoiinated membrane products, as determined by wide- and small-angle X-ray studies. J Polym Sci Pol Phys 19 1687-1704... 

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