Synthesis of functionalized phenolformaldehyde polymer resins by the reaction of 2,4‐dihydroxyacetophenone formaldehyde resin with various amines and their metal ion uptake properties

A series of functionalized phenolformaldehyde polymer resins have been synthesized by the reaction of 2,4‐dihydroxyacetophenone‐formaldehyde resin with the amines, such as ethanolamine, aminophenol, ethylenediamine, and propylenediamine in dichloromethane. The Schiffbase polymers were characterized by IR and ¹H‐NMR spectroscopic techniques. Thermal stabilities of the polymers were determined by TG and DTA studies. Heavy and toxic metal ions viz., Pb(II), Hg(II), Cd(II), and Cr(VI) have been removed using these polymer resins. Metal uptake efficiency, reusability, effect of pH, effect of time, and effect of initial concentration on the metal uptake were also studied. Amount of metal removed by the resin was determined using atomic absorption spectrophotometry. The retention properties were also tested under competitive conditions and were found to be depend strongly on the pH. Elution of metal ions were investigated in acid media. The uptake behaviour of the resins was approximately described by Freundlich's equation. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1501–1509, 2004