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The paper deals with the surface modification of a heterogeneous cation-exchange membrane with the application for electrodialysis, electrodeionisation, and electrolysis. CM(H)-PP (cation exchange membrane based on polyethylene binder) membrane was covalently attached with poly(divinylbenzene-co-4-vinylbenzylchloride). We have achieved better properties than commercially available heterogeneous ion-exchange membranes in the field of chemical, electrochemical properties by the formation of layer. Ion-exchange capacity was determined with maximum value 2.99 meq g−1 dry matter, area resistance 9.9 Ω cm2 and specific resistance 149 Ω cm, permselectivity 93.4%. [ABSTRACT FROM AUTHOR]

The work deals with the selection of sulfonating agent and preparation of polymeric coating on membrane step by step. The surface modification of a commercial ultrafiltration polyethersulfone (PES) membrane was covalently attached to the poly(styrene‐co‐divinylbenzene‐co‐4‐vinylbenzylchloride). The whole process was tracked step by step using analytical methods. Chlorosulfonic acid and trimethylsilyl chlorosulfonate were tested as sulfonating agents. Ion‐exchange capacity (IEC), water content, specific resistance, and permselectivity were measured and scanning electron microscope analyzed the surface of the cation exchange membrane. The best results were achieved using 5 wt % chlorosulfonic acid as sulfonating agent. IEC reached values of up to 2.44 meq g−1 of dry matter, permselectivity of 93.6%, area resistances of 10.1 Ω cm2, and specific resistance around 299 Ω cm. The prepared cation exchange PES membrane with chlorosulfonic acid can be used in electrochemical processes, for example, in electrodialysis. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48826. [ABSTRACT FROM AUTHOR]

The present work deals with verification stability of the prepared anion-exchange membrane with surface modification in the time. The surface modification of a commercial ultrafiltration poly(ethersulfone) membrane was carried out graft polymerization. Poly(styreneco- divinylbenzene-co-4-vinylbenzylchloride) surface layer was covalently attached onto commercial ultrafiltration support layer. The membrane was tested from the point of view of water content, ion-exchange capacity, specific resistance, permselectivity, FT-IR spectroscopy and SEM analysis. The tested characteristics (IEC, permselectivity, resistances, structure) of the prepared membrane were same after one year from preparation. The prepared membranes can find use in electrodialysis processes. [ABSTRACT FROM AUTHOR]

Nitrate concentration in surface and groundwater is becoming a global concern. The electrodialysis is a useful separation technique that uses ion-exchange membranes to treat the solution, and these membranes can possess certain selectivity towards different ions. The objective of this work was to compare the possibility of nitrate separation form a mixed salt solution by electrodialysis using three different anion-exchange membranes (AEMs). Characteristic properties of heterogeneous AEMs are mainly defined by their composition, a mixture of a polymer matrix and an anion-exchange resin. In this work, three different kinds of anion-exchange resins with distinct functional groups (trimethylamine and dimethylethanolamine) were used to prepare AEMs, in which selectivity towards nitrate ion was compared by desalination of mixed salt solution using laboratory electrodialysis unit. The solution used was composed of NaCl, NaNO3, NaH2PO4, and Na2SO4, every salt of concentration 0.05 mol L−1. Although the properties of individual AEMs and their courses of desalination differed significantly, all membranes had higher selectivity for nitrate ions than for the remaining ones; however, their selectivity towards nitrate and chloride was very similar. The affinity relationship of the AEMs was: nitrate > chloride > dihydrogen phosphate > sulfate. [ABSTRACT FROM AUTHOR]

Aims: The main feature of fibrosing idiopathic interstitial pneumonias (fIIPs) is the fibroproliferative potential of underlying pathogenetic process. We hypothesize that the concentration of potential markers of fibroproliferative healing, PAR-2, TGF-β1, TNF-α and IL-4Rα in bronchoalveolar lavage fluid (BALF) differ in patients with fIIPs compared to controls (C)., Patients and Methods: 10 patients with fIIPs and 9 controls (C) were included to the study. Concentrations of CD124 (IL4Rα), PAR-2, TGF-β1 and TNF-α in BALF were determined using the ELISA method., Results: We observed higher concentrations of IL4Rα (fIIPS 1499.4 pg/ml vs C 255.5 pg/ml; p < 0.05), PAR-2 (fIIPS 1807.9 pg/ml vs C 421.0 pg/ml; p < 0.05) and TGF-β1(fIIPS 283.0 pg/ml vs C 197.1 pg/ml; p < 0.01) in BALF in fIIPs versus C. The values of TNF-a in BALF did not differ significantly in fIIPs compared to controls. The ratios also showed differences in fIIPS and C: IL4Rα/TGF-β1 (fIIPS 6.19 vs C 0.68; p = 0.0143); TNF-α/IL4Rα (fIIPS 0.84 vs C 7.93; p = 0.043); TGF-β1/TNF-α (fIIPS 0.21 vs C 0.16; p = 0.0179) and protein/PAR-2 (fIIPS 0.06 vs C 0.28; p = 0.0033)., Conclusions: We found that PAR-2, TGF-β1 and IL-4Rα are significantly up-regulated in the BALF of fIIPs compared to controls, therefore we suppose they could become biomarkers of fibroproliferative healing.