Synergistic Fabrication of Magnetic Hypercrosslinked Porous P(VBC-DVB-AA)@Fe3O4 Microspheres for Removal of Cationic Dye

Hypercrosslinked porous polymers have become a hotspot of research by virtue of their high specific surface area, mild synthesis conditions, and wide source of monomers, which are promising adsorbents for water treatment. In this paper, 4-vinylbenzylchloride (VBC), acrylic acid (AA) and divinylbenzene (DVB) were used to prepare crosslinked microspheres as a template by reflux precipitation polymerization. On this basis, porous microspheres were prepared by hypercrosslinking reaction using FeCl3 as catalyst. Next, excess FeCl3 was used as iron sources for the next solvothermal reaction to prepare magnetic hypercrosslinked P(VBC-DVB-AA)@Fe3O4 microspheres (MHCPMs). The elution step of the hypercrosslinked product was omitted, while magnetic Fe3O4 was introduced. MHCPMs have uniform particle size, high specific surface area, superparamagnetism and abundant functional groups. After synergistic preparation, the specific surface area of the MHCPMs-60 was still as high as 654.56 m(2)/g, and the saturation magnetization strength reached 29.0 eum/g. The magnetic microspheres could be directly aggregated and separated in the presence of an applied magnetic field. In addition, MHCPMs were well dispersed in water after vigorous shaking and could be used to adsorb the cationic dye quickly and efficiently. The adsorption results for methylene blue (MB) well conformed to the Langmuir model (R-2 = 0.999) with a maximum adsorption of 214.26 mg/g and followed the pseudo-first-order kinetic model. In addition, the MHCPMs-60 showed good reusability and stability over seven cycles. Therefore, this study proposed a synergistic strategy for the preparation of magnetic porous polymer microspheres, which exhibited a significant potential application value in many fields.