Effect of Porosity on Ion Transport Through Polymers and Polymer-Based Composites Containing Inorganic Nanoparticles (Review)

Abstract

The development of nanotechnologies gives a new impulse to chemistry of polymer ion exchange resins and membranes, which are related to nanomaterials. When they are in contact with water or other polar solvent, the system of nanopores is formed. First, this feature has been found for homogeneous perfluorinated membranes (PFMs) of Nafion type [1, 2]. Then, it was proved for other polymer ion exchange materials (heterogeneous membranes and resins) [3, 4]. The nanopores are hydrophilic; they provide ion transport and ion exchange ability of swollen polymers. Their porous structure involves also hydrophobic pores; their size is from several tens of nanometers to several tens of microns. Both hydrophilic and hydrophobic pores are available for any inorganic modifier: the filler affects functional properties of the composite. The most intensive work in the field of practical application of organic-inorganic ion exchange materials has been started since the 2000s [5]. The necessity of investigations was caused by requirements of technologies for alternative energy and separation.