Electrospun Polyacrylic Acid‐Functionalized Poly‐Cyclodextrin Fibers for Efficient Heavy Metal Removal from Water

Abstract

ABSTRACT Electrospun poly‐cyclodextrin (poly‐CD) fibers grafted with poly(acrylic acid) (PAA) were produced for effective heavy metal removal from water. CD fibers were first fabricated via electrospinning, then subjected to post‐heat treatment for esterification, yielding poly‐CD fibers. Subsequently, PAA was attached to poly‐CD via Cu‐catalyzed azide‐alkyne cycloaddition. Alternatively, acrylic acid was polymerized directly on poly‐CD fibers using reversible addition–fragmentation chain transfer (RAFT) polymerization, yielding PAA/poly‐CD fibers. The structure and morphology of the PAA/poly‐CD fibers were examined using Fourier‐transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), confirming successful modification while maintaining fibrous structure. The fibers exhibited a strong affinity for heavy metal ions, with removal efficiencies assessed through inductively coupled plasma mass spectrometry (ICP‐MS) analysis. Modifying poly‐CD with PAA enhanced its adsorption performance by up to 49%. They effectively removed multiple heavy metal ions, including Mn 2+ , Ni 2+ , Cu 2+ , Zn 2+ , and Cd 2+ , with the highest sorption observed for Cu 2+ , followed by Cd 2+ and Zn 2+ . Notably, the PAA/poly‐CD fibers demonstrated very high performance of removal (77%–100%) at lower concentrations for all tested metal ions and retained high efficiency for specific metal ions like Cu 2+ and Cd 2+ (73%–89%) even at high concentrations of 50 ppm, highlighting their potential for heavy metal removal from water.