Swelling Behavior and Adsorption Properties of Multicomponent PF127DA/P (AA-AM)/PVA Hydrogel

In this study, an adsorbent capable of rapidly adsorbing heavy metal ions was prepared using PVA crosslinked with PF127DA and AA/AM. The swelling behavior of the hydrogel in salt solutions was investigated based on the Flory-Huggins theory model. The results indicated that the theoretical predictions of the hydrogel's volume swelling ratio, derived from the Flory-Rehner swelling theory and the Donnan equilibrium, were in agreement with the experimental swelling data of the hydrogel in water and salt solutions. With the increase in the amount of crosslinking agent PF127DA, the water absorption swelling ratio of the composite material was reduced by half, with the volume swelling ratio decreasing from 3.56 to 2.33. When the concentration of cations in the salt solution increased from 10^-5 mol/L to 10^-1 mol/L, the volume swelling ratio of the hydrogel showed a decreasing trend, which in turn affected the adsorption performance of the pollutant. Therefore, increasing the amount of crosslinking agent can enhance the colloidal strength, provided that its swelling properties are not compromised. Additionally, the presence of high concentrations of salt can affect the adsorption behavior of the hydrogel, and appropriate measures should be taken in practical applications to avoid its impact on adsorption behavior.