<p>In this study, a novel poly(vinyl alcohol) (PVA) membrane modified with L-glutamic acid was synthesized using poly(ethylene glycol) (PEG) as a porogen to increase the surface area and improve Cu(II) adsorption. The phase separation between PVA and PEG induced pore formation, extending from the surface into the interior. PEG also acted as a plasticizer, increasing polymer chain flexibility. The effects of the PEG content on the structural and physicochemical properties were analyzed via water absorption, FT-IR, TGA, XRD, and SEM. The results showed that the incorporation of PEG significantly influenced the material properties. Additionally, adsorption, desorption, kinetic, and isotherm studies were conducted to evaluate the adsorption process. The Cu(II) adsorption capacity increased from 31.8 mg/g to 51.1 mg/g with an initial Cu(II) concentration of 95.0 mg/L. The adsorption equilibrium followed the Freundlich isotherm model, suggesting a heterogeneous surface with various adsorption sites. Kinetic analysis revealed pseudo-second-order kinetics. Desorption studies revealed efficient Cu(II) release in 2 M HNO₃ within 150 min, resulting in an 81.9% desorption efficiency. Thermal analysis revealed a lower degradation range (262 °C) compared to that of pure PVA (339 °C), which was attributed to the increased surface area. Additionally, the incorporation of PEG reduced the crystallinity of PVA-c-Glu/PEG. These findings highlight the potential of PEG-modified porous PVA for sustainable heavy metal removal in environmental applications.</p>