Ion-selective membranes have a high degree of separation of the solutions, both with low and high concentrations of dissolved salts. Besides solutions using ion selective membrane occurs in the low operating pressures of 0.1-2 bar, depending on the substrate to which the working layer is applied. Lately, in the production of conductive polymers are used, such as polyaniline (PANI), for example for the manufacture of solar cells, sensor devices, for making protection from electrostatic charges and corrosion, as well as ion-exchange membranes. Use in the preparation of PANI, or modification has the advantages of ion exchange membranes in the communication and availability of raw materials and ease of manufacture and also because of such quality as high selective permeability. Modification of membranes to form on the surface and in the pores of the PANI layer, which is a cationic, allows to obtain ion-exchange membranes are not inferior in selectivity by reverse osmosis on a number of cations. The aim is to establish the chemical nature of using FTIR spectroscopy layer surface modification of PTFE and nylon membranes by polymerization of aniline and the study of possible changes in the properties of membranes such as exchange capacity and moisture content. In this operation the composite membranes prepared from cation-modified surface layer on the substrate a polyaniline and nylon of PTFE. The results of the study by infrared spectroscopy of the molecular structure of polyaniline and a number of materials on its basis.

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Ion-exchange membranes are widely used in modern technologies, particularly in the field of water treatment and make it possible to considerably reduce expenses for wastewater treatment and ensure high degree of purification. Currently, perfluorinated sulfated proton-conducting membranes are often used, such as NAFION and its Russian analogue, MF-4SK based on co-polymerization product of a perfluorinated vinyl ether with tetrafluoroethylene. However, with development of the industry, materials with improved properties and lower cost are required. The aim is to obtain ion-exchange membranes for water treatment from metal ions and to study physico-chemical properties of obtained membranes. In this study, cation exchange composite membranes with modified polyaniline surface layer on nylon and PTFE substrate have been obtained. Changes in the structure of membranes were recorded using a microscope. Throughput capacity of the membranes was determined by passing a certain volume of distilled water through the membrane. The experiment intended to determine electivity of membranes was performed by passing a certain volume of metal salt solutions of a known concentration, after which the filtrate was collected. Concentrations of the studied metal ions in the original solution and in the filtrate were determined by the method of atomic adsorptive spectrometry with electro thermal atomization "Quantum Z.ETA". Prepared highly selective ion exchange membranes. Properties of modified membranes, such as selective permeability and ion-exchange capacity have been determined. The membranes feature high selectivity for heavy metal ions. Moisture-retaining power and swelling ability of the membranes have been studied. Selectivity of the membrane to heavy metal ions is between 70 and 99%. Ion-exchange capacity of the obtained nylon polyaniline membrane is not inferior to some commercially available cation-exchange membranes. Use of the modified membranes in the stage of tertiary wastewater treatment will ensure achieving established standards.

We present an experiment of densification of a zn horizontal assembly made of regular pentagons. The annealing leads to a dense crystalline arrangement with quasisixfold symmetry in spite of the geometrical characteristics of the grains and of the apriori short-range correlation length in the packing. ? l i s configuration yields the maximum average number of side to side contacts between the &os and probably the maximum packing fraction.

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