Copolymerization of 2-(perfluorohexyl)ethyl methacrylate with divinylbenzene to fluorous porous polymeric materials as fluorophilic absorbents.

Functionalized porous polymeric materials have a good potential for adsorption application owing to their abundant porosity, group tunability and chemical stability. Up to now, few studies have been reported on the fluorous porous polymers. Here, we report a solvothermal synthesis of fluorous porous poly methacrylate-divinyl benzene (FPMD) materials through a copolymerization of 2-(perfluorohexyl)ethyl methacrylate (C6Rf) and divinylbenzene (DVB) in an autoclave. Various techniques, such as nitrogen adsorption-desorption, Fourier-transform infrared spectrometer (FTIR), scanning electron microscope (SEM), thermogravimetric analyzer (TG), X-ray photoelectron spectroscopy (XPS) and so on have been used to characterize the structure and morphology of the synthesized FPMD samples. It is found that C6Rf could copolymerize with DVB to form porous networks through a solvothermal reaction. The molar ratio of C6Rf and DVB as well as the solvent are closely related to the porosity of the FPMD. The porosity descends and even disappears when increasing the molar ratio of C6Rf/DVB to 1 in case of ethyl acetate as the solvent. While a fluorous solvent of hydrofluoroether (HFE-7300) is used, a FPMD with porous structure can be obtained at the same ratio. The fluorous solvent may favor the stretch of the fluorocarbon chains of C6Rf and thus produce porosity during the copolymerization. HFE-7200 with a lower boiling point has also been used as the fluorous solvent, finding that the pore structure of FPMD transforms to a typical bottle-shape mesopore structure. Pure solvent absorption tests indicate that the adsorption capacities to toluene, isopropanol and hydrofluoroether (HFE-7200) are 4.7, 6.2 and 7.8 ml/g, respectively, on the optimized FPMD material. The absorption capacity of HFE-7200 is higher than that of toluene and isopropanol, illustrating the fluorophilicity of the fluoridated porous materials. Image 1 • Fluorous porous poly methacrylate-divinyl benzene (FPMD) monoliths are obtained. • 2-(Perfluorohexyl)ethyl methacrylate copolymerized with divinylbenzene to FPMD. • Hydrofluoroethers are good solvents for the construction of FPMD. • FPMD exhibits superhydrophobicity, mesoporosity and rich F content. • Absorption capacity to fluorous solvent is higher than toluene in FPMD. [ABSTRACT FROM AUTHOR]