Tefzel electrical

Water absorption of Tefzel is low (0.029% by weight), which contributes to its outstanding dimensional stabiUty as well as to the stabiUty of mechanical and electrical properties regardless of humidity. 

Fig. 61. Schematics of pressure-induced and applied-potential-induced BLM deformations. Application of hydrostatic pressure (by lowering a piston into the aqueous solution bathing the cis side of the BLM) displaces the BLM from position 1 to position 2. The displacement involves both translational (lateral) motion (Ft) and curvature increase (Fc). As indicated, deformation of the BLM is accompanied by a change in its torus (Plateau-Gibbs border). 2R and 2Rm represent the diameters of the aperture of the pinhole in the Tefzel film and that of the membrane (excluding the torus). The object laser beam, incident upon the trans side of the BLM and reflected by it at 45° at a shortened wavelength produces concentric optical interference fringes with the reference laser beam. Ag/AgCl electrodes, placed in the cis and trans sides of the BLM, allow for continuous electrical measurements [413]...

A copolymer of ethylene and tetrafluor-oethylene (DuPont Tefzel ), ETFE is readily processed by extrusion and injection molding. It has excellent resistance to heat, abrasion, chemicals, and impact, with good electrical properties. 

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