Preparation of poly(GMA-co-PEGDA) microbeads modified with iminodiacetic acid and their indium adsorption properties

Poly(glycidyl methacrylate-co-poly(ethylene glycol) diacrylate) (poly(GMA-co-PEGDA)) microbeads were synthesized by suspension polymerization and modified with iminodiacetic acid. The structures and morphologies of the microbeads were confirmed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). Bands at 1250 cm−1, 912 cm−1 and 765 cm−1 resulted from symmetric stretching of the epoxy ring, asymmetric ring stretching of the CC bond and a 12 micron band, respectively. The synthetic yields, ion-exchange capacities and water uptake were investigated. The maximum adsorption predicted by the Langmuir adsorption isotherm and Freundlich adsorption model and poly(GMA-co-PEGDA) modified with IDA is considered to be adsorb into a mono-layer. The thermodynamic parameters (ΔG°, ΔH° and ΔS°) of the microbeads dependent adsorption isotherms and indicate that the adsorption was spontaneous and exothermic.