MAPTAC-Functionalized Poly(acrylic acid-co-sodium acrylate) Hydrogels for Enhanced Pb(II) and Cd(II) Adsorption
Year: 2026
Type: preprint
Abstract: Heavy metals are among the most hazardous environmental pollutants, necessitating the development of efficient materials for their removal from contaminated water. In this study, a poly(acrylic acid-co-sodium acrylate) hydrogel was synthesized and functionalized with 3-(Methacryloylamino)propyltrimethylammonium chloride (MAPTAC). The synthesized hydrogels were characterized using various analytical techniques. Rheological and dynamic mechanical thermal analysis demonstrated that MAPTAC modification enhanced the storage modulus and improved the thermo-mechanical stability of the hydrogel by forming a stronger and more stable polymer network. The modification also reduced the equilibrium swelling capacity while improving the structural integrity of the hydrogel, indicating the formation of a more compact and mechanically stable polymer network. Their adsorption behavior of synthesized hydrogels toward Pb(II) and Cd(II) ions was investigated. Among all formulations, the hydrogel containing 10 g MAPTAC showed the highest adsorption capacities of 118 mg/g for Pb(II) and 117 mg/g for Cd(II), with corresponding removal efficiencies of 94.5% and 94%. Adsorption was systematically evaluated as a function of solution pH, contact time, adsorbent dosage, temperature, and initial metal-ion concentration. The optimal adsorption conditions were pH 6, a contact time of 60 min, a temperature of 25°C, and an adsorbent dosage of 0.008 g. The equilibrium data were best described by the Freundlich isotherm model, while adsorption kinetics followed the pseudo-second-order model. Thermodynamic analyses indicated that the adsorption process was spontaneous and most favorable at 25°C. These findings demonstrate that the MAPTAC-functionalized poly(acrylic acid-co-sodium acrylate) hydrogel is an efficient and promising adsorbent for removing Pb(II) and Cd(II) from aqueous media.
Source: Research Square
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7225425869