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Ion exchange equilibria Cl−– NO 3 - , Cl−– SO 4 2 - , NO 3 - – SO 4 2 - on fibrous strong base anion exchangers on the basis of graft copolymer of styrene and divinylbenzene to polypropylene fibers with groups of benzyl trimethyl- (TMA), triethyl- (TEA), and tributyl- (TBA) ammonium have been studied and characterized by values of the equilibrium coefficients and separation factors. They were compared with the same equilibria on ion exchange resins Dowex1 with different cross-linkage. An equation allowing calculating the separation factor for different ionic concentrations and ratios of the ions in solutions of uni- and divalent ions from the equilibrium coefficient invariant to the concentration has been derived. The selectivity of nitrate and chloride sorption increases with increasing size of alkyl radicals in the functional group and with increasing percent of divinylbenzene in the resins. A quantity characterizing selectivity of ion exchanger to bivalent ion against the univalent ion named concentration of zeroth selectivity (CZS) has been suggested to describe the efficiency of ion exchangers in processes of water purification from univalent ions, specifically nitrates in waters containing sulfates. At concentrations above the CZS the univalent ion is absorbed selectively compared to the bivalent one; the “dumping effect” in frontal chromatograms of mixtures of such ions is not possible above the CZS point and this criterion can be used for choosing the ion exchanger for selective removal of univalent ions from mixtures with polyvalent ones. The CZS values for conventional strong base ion exchangers in ion exchange NO 3 - – SO 4 2 - is higher than typical total ionic concentrations in drinking waters (1–3 × 10−3 eq/L). For Dowex1 × 10 it was found equal 1.3 × 10−2 eq/L. For the fibrous ion exchanger with benzyltributylammonium groups CZS = 3.3 × 10−6 eq/L. This ion exchanger is suitable for selective removal of nitrates from the solutions with concentrations higher than this value and has exceedingly high selectivity to nitrates which makes the process of its regeneration difficult. The most suitable fibrous ion exchangers for application in drinking waters purification from nitrates with guarantied absence of the nitrate dumping appeared FIBAN A-1 TEA having the CZS values 4.3 × 10−4 eq/L.

The anion exchange fibers on the basis of industrially produced polyacrylonitrile fiber NITRON with different strong and weak base groups have been described in the paper. Their acid–base properties were characterized by the acidity parameters calculated from the potentiometric titration curves. The method of computer analysis of the titration curves described elsewhere was used. It was established that the ion exchange fibers are polyfunctional and contain at least four types of functional groups. Their capacities and the acidity parameters have been calculated. The fibers have full ion exchange capacity about 3.5 meq/g. The capacity according to the strong base quaternary aminogroups (p K ≅ 2) is usually about 2.5 meq/g. The water uptake, stability in hydrogen peroxide solutions, strong acids and alkalis of different concentrations at the ambient temperature and 100 °C have been studied. The fibers do not loose significantly their anion exchange capacities and mechanical properties except for the most extreme regimes of their treatment. At the same time they accumulate carboxylic acid groups in their structure due to hydrolysis of the residual nitrile groups in the fiber.

Fibrous ion exchangers (FIBAN) have been studied in a model process of water softening and removal from water simultaneously present heavy metal ions: Co2+, Ni2+, Zn2+, Cd2+, Cu2+, Pb2+. The effect of the following factors on the efficiency of Ca2+ removal from a model solution has been studied: the filtering bed height (7–40 mm); density of the column packing corresponding to the volume capacity, 0.17–0.83 meq/cm3; solution flow rate (4–37cm/min). A fibrous sulfonic-type ion exchanger in shallow beds has exhibited a high efficiency in removal Ca2+ from water, greatly exceeding efficiency of a conventional sulfostyrene resin studied in parallel. In all cases high breakthrough capacities corresponding to the degree of column utilization, 0.6–0.9, have been observed. In the processes of water purification from heavy metal ions the highest efficiency was observed for chelating fibrous ion exchanger with iminodiacetete groups. A granular resin of the same type had much lower efficiency. Fibrous ion exchangers can find a wide application in water treatment processes.

A fibrous sorbent possessing abundant micropore structure was firstly prepared via post-crosslinking reaction on the PP-ST-DVB original fiber. Its micromorphology and sorptive properties were investigated, and the results demonstrated that the novel fibrous hypercrosslinked sorbent has narrow pore-size distribution, small average porous radius (1.90 nm), high specific surface area (362.31 m 2 /g), and fine sorptive properties for small organic molecules.

The dispersity of ferrophase particles and the interaction with a surfactant in magnetic liquids based on magnetite stabilized by oleic acid are investigated. It is shown that oleic acid at the surface of the ferrophase is free and/or chemically bound. When preparing and aging the magnetic liquid, oleic acid undergoes an oxidative destruction; the partial oxidation of magnetite can also occur. Recommendations for stabilization of the magnetic liquid properties and constitution are stated.

The method of radiography at large and small angles has been used to study the structure of oriented PP fibres modified by grafted polymerization of styrene and also the anion-exchange fibres obtained from them by polymer-analogous conversions. PS forms discrete grafted structures which are detected in the grafted fibres after its chloromethylation. The size and shape of the grafted structures change on polymer-analogous conversions.

Orientated films of polymethylmethacrylate and polybutylmethacrylate have been modified by graft polymerization of acrylonitrile (AN), under conditions ensuring preservation of the oriented structure of the matrix with uniform distribution of PAN through the cross section of the films. Even when the PAN content is low the matrices have the physico-chemical properties of network polymers, although they are not chemically crosslinked. Particles of PAN microphase function as active reinforcing agents.

Physico-chemical properties, structure and possible application of the “Fiban” fibrous ion exchangers are reviewed. The materials described belong to strong-acid, strong-base and polyampholite types. They can be produced in the form of threads, cloths, non-woven materials, etc. Methods of their application as means for air purification from acid or base impurities are described. Examples of their use as chromatographic materials and absorbents are presented (separation of simple inorganic cations and anions, heavy cations, amino acids, removal of chromium(VI) from water).

IR spectroscopy is used in a kinetic study of the accumulation of ends of broken PE macromolecules in loaded PE films reinforced with grafted discrete polystyrene structures. The rate of mechano-chemical degradation of PE in the graft films is considerably lower, and the maximum concentrations of broken macromolecules several times higher, compared with the original PE. The process is described by an equation for monomolecular breakdown, the parameters of which coincide with the corresponding parameters of a durability equation which were based on the results of independent durability measurements carried out for the same samples. Under identical conditions the lifetime of the loaded graft films considerably exceeds that of the original films.