Structure of perfluorinated membranes investigated by method of standard contact porosimetry

The results of investigation of various factors influencing water distribution in perfluorinated membrane structure by method of standard contact porosimetry are summarized. The Nafion membranes (Dupon de Nemoure, USA) and MF-4SK membranes ("Plastpolymer", Russia) were the objects of the research. The influence of production process and conditioning method on porosimetric curves of perfluorinated membrane is discussed. New results related to the porosity of perfluorinated membranes after reinforcing fabric introduction and processing by organic solvents are reported. The role of the modifying components of various nature in the shaping of transport channels in perfluorinated membrane is studied. The influence of polyaniline and hydrogen zirconium phosphate on water distribution in membrane structure is revealed. The correlation between the maximum porosity value of the membrane and its diffusion and electroosmotic permeability, as well as between the fraction of the gel pore volume and membrane selectivity is established. It allows the prediction of possible changes in the structural characteristics and also in the transport properties of the membranes under the influence of the modifying components of different types and various operating conditions. (C) 2014 Elsevier B.V. All rights reserved.