Uniaxial extension, morphologies

Elliott and co-workers performed a detailed SAXS investigation of the morphology of Nafion membranes that were subjected to uniaxial and biaxial deformation. For as-received membranes, manufactured by Du Pont using an extrusion process, the cluster reflection was shown to exhibit a limited degree of arching in the direction perpendicular to the machine direction. Upon uniaxial extension, this arching was observed to increase in a manner consistent with previous studies. This arching was rationalized on... 

The method of morpholgy control should involve the fibrillation step. When fine droplet dispersion is desirable, the resins should be selected to assure low X, the uniaxial extension should be maximized and imposition of a fiber disturbing dynamic field should be used at the end of the process. On the other hand, if preservation of extended morphology is desired, (i.e., the... 

Case 1 Mn < M. The structure of uniaxially aligned LMW PF2/6 has been recently studied by combination of optical spectroscopy, NEXAFS and GIXRD, Fig. 22 exhibits a representative NEXAFS data and the subsequent analysis. These data support a structural model in which there is a graded morphology such that the top and bottom surfaces exhibit extensive planar, uniaxial alignment while the film interior is less well oriented and includes both planar and tilted (i.e., non-planar) PF2/6 chains [114]. 

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