Investigation of electrochemical characteristics of intergel systems based on polyacrylic acid

Abstract

Currently, hydrogels are polymer materials in high demand due to their physicochemical properties, and recent years have seen significant attention given to the study of their physicochemical properties [1,2]. The purpose of this research is to investigate the effect of remote interaction on the electrochemical properties of intergel systems containing hydrogels of polyacrylic acid, poly-4-vinylpyridine, poly-2-methyl-5-vinylpyridine, and polyethyleneimine hydrogels with various initial states. The dependency of conductivity and pH levels in aqueous solutions of intergel systems was examined. The obtained results have shown thatin the 5:1 ratio of the PAAswollen:P4VPdry intergel system, the conductivity of the aqueous medium reaches its maximum value after 24 hours, with a corresponding decrease in pH level. For the PAAdry:P2M5VPdry hydrogels at ratios of 5:1, 1:5, and 2:4, the high electroconductivity was observed at the sixth hour. The maximum pH value was achieved at a ratio of 4:2, indicating a low presence of nitrogen heteroatoms in the aqueous solution. The maximum conductivity in the PAAswollen:PEIswollen system at a 3:3 ratio was reached after 8.5 hours, while the pH showed its minimum value. In the study of the PAAdry:PEIdry intergel system, the pH of the aqueous medium decreased over time in all hydrogel ratios. An exception was noted at a 4:2 ratio, where pH slightly increased after 0.5 hours, then fell again, showing a deviation from the general pH trend. Conclusion. The conducted research has shown that specific conductivity varies across all molar ratios of hydrogels. It was established that changes in pairs and states of hydrogels in the intergel system affect specific conductivity, indicating the ratio of ionized and dissociated groups in the chain changes normally. These results demonstrate that these intergel systems can be used to get high-selectivity sorbents.