Anomalous Sorption of Yttrium Ions by the Mutual Activated Hydrogels in the Interpolymer System of Poly(Methacrylic Acid) and Poly(4-Vinylpyridine)

This paper considers the effect of mutual activation of poly(methacrylic acid) (PMAA) and poly-(4 vinylpyridine) (P4VP) hydrogels during their remote interaction on the degree of yttrium ions sorption from an aqueous medium. Electrochemical properties were studied by conductometry and pH measurements to predict the activation possibility of these hydrogels. pH measurements showed that at 0.1 hour, the pH values were the lowest, indicating a high content of H⁺ ions in the aqueous solution. An increase in the interaction time to 24 hours leads to an increase in pH values, indicating a decrease in the content of H⁺ ions in the solution. The dependences of the specific electrical conductivity were studied. The experiments showed that the maximum values were observed at the ratios of 3 : 3 and 1 : 5 (gPMAA : gP4VP), which coincided with the result of pH measurements. The obtained results indicate the significant changes occurred in the electrochemical and conformational values of the initial macromolecules in the interpolymer system. Our research confirms the presence of remote interaction between hydrogels and their mutual activation.