Adsorption of anionic dyes on a reversibly swelling cationic superabsorbent polymer

Abstract

A cationic monomer [2‐(methacryloyloxy)ethyl]trimethylammonium chloride was polymerized using N,N′‐methylenebisacrylamide as the crosslinker to obtain a cationic superabsorbent polymer (SAP). This SAP was characterized by Fourier transform‐infrared spectroscopy, and the equilibrium swelling capacity was determined by swelling in water. The SAP was subjected to cyclic swelling/deswelling in water and NaCl solution. The conductivity of the swelling medium was monitored during the swelling/deswelling and was related to the swelling/deswelling characteristics of the SAP. The adsorption of five anionic dyes of different classes on the SAP was carried out and was found to follow the first‐order kinetics. The Langmuir adsorption isotherms were found to fit the equilibrium adsorption data. The dye adsorption capacity of the SAP synthesized in this study was higher than that obtained for other hydrogels reported in the literature. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Negative Solvatochromism of an Anionic Thiazole‐Based Dye

“…Dyes such as methyl orange, phenolphthalein, or bromothymol blue are well‐investigated for this purpose. Ionic and especially anionic dyes are used in various independent fields as analytical probes, for example, to study interactions of anionic compounds and cationic surfactants,1 as selective chemosensors for both anions and cations,2 and to characterize the adsorption behavior of superabsorbent polymers (SAPs),3 solid agricultural waste, modified charcoal,4 or other compounds that are used as filter materials 5. Another main application of (solvatochromic) dyes is to measure the properties, that is, the polarity of solvent and solvent mixtures 6.…”

Synthesis and swelling property of superabsorbent starch grafted with acrylic acid/2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid

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