Three composite reverse osmosis membranes were prepared from m-phenylenediamine (MPD) and trimesoyl chloride (TMC), 5-chloroformate-isophthaloyl chloride (CFIC), 5-isocynate-isophthaloyl chloride (ICIC) respectively t...Three composite reverse osmosis membranes were prepared from m-phenylenediamine (MPD) and trimesoyl chloride (TMC), 5-chloroformate-isophthaloyl chloride (CFIC), 5-isocynate-isophthaloyl chloride (ICIC) respectively through the interfacial polymerization technique on the polysulphone supporting membrane.The membranes produced were characterized by using permeation experiments with salt water, attenuated total reflectance infrared (ATR-IR), and X-ray photoelectronic spectroscopy (XPS).This study showed that with the increase of NaCl concentration, the flux of the three membranes decreased; the rejection of TMC/MPD, ICIC/MPD composite membranes increased firstly and then decreased; but the rejection of CFIC/MPD composite membrane kept steady.According to the ATR-IR and XPS results, the active layer of three membranes was composed of crosslinked polymer and linear polymer with pendant; all three composite membranes contained amide functional group( —CONH? ゛nd carboxyl acid functional group( —COOH ); the ICIC/MPD composite membrane contained urea functional group( —NHCONH? ? the CFIC/MPD composite membrane also contains urethane functional group( —OCONH? ゛nd hydroxyl functional group( —OH ).The hydroxyl functional group could lead to high rejection and low flux.展开更多
Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized an...Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized and characterized by X-ray diffraction of the single-crystal and fluorescence spectra. Complex 1 crystallizes in triclinic system, space group P1 with a=0.559 62(7) nm, b=0.777 58(6) nm, c=0.969 75(10) nm, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, and Z=1. Final R=0.024 8(wR=0.078 5). Complex 2 belongs to orthorhombic system, space group Pbca with unit cell dimensions a=1.144 94(19) nm, b=1.209 69(6) nm, c=1.740 73(8) nm and Z=8. Final R=0.018 5(wR=0.034 8). Both the two complexes are coordination polymers with a two-dimensional infinite structure, the repeat unit is [Cd 2(C 10H 2O 8)(H 2O) 6] (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] (2) which are bridged by the ligands of 1,2,4,5-benzenetetracarboxyl(C 10H 2O 8) and nicotinato(NA), respectively. The two polymers show strong fluorescence with λ em=433 nm(λ ex=333 nm, 1) and λ em=423 nm(λ ex=330 nm, 2) in the solid state at room temperature. The emissions observed in the polymers are tentatively assigned to the ligands fluorescence(LLCT).展开更多
文摘Three composite reverse osmosis membranes were prepared from m-phenylenediamine (MPD) and trimesoyl chloride (TMC), 5-chloroformate-isophthaloyl chloride (CFIC), 5-isocynate-isophthaloyl chloride (ICIC) respectively through the interfacial polymerization technique on the polysulphone supporting membrane.The membranes produced were characterized by using permeation experiments with salt water, attenuated total reflectance infrared (ATR-IR), and X-ray photoelectronic spectroscopy (XPS).This study showed that with the increase of NaCl concentration, the flux of the three membranes decreased; the rejection of TMC/MPD, ICIC/MPD composite membranes increased firstly and then decreased; but the rejection of CFIC/MPD composite membrane kept steady.According to the ATR-IR and XPS results, the active layer of three membranes was composed of crosslinked polymer and linear polymer with pendant; all three composite membranes contained amide functional group( —CONH? ゛nd carboxyl acid functional group( —COOH ); the ICIC/MPD composite membrane contained urea functional group( —NHCONH? ? the CFIC/MPD composite membrane also contains urethane functional group( —OCONH? ゛nd hydroxyl functional group( —OH ).The hydroxyl functional group could lead to high rejection and low flux.
文摘Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized and characterized by X-ray diffraction of the single-crystal and fluorescence spectra. Complex 1 crystallizes in triclinic system, space group P1 with a=0.559 62(7) nm, b=0.777 58(6) nm, c=0.969 75(10) nm, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, and Z=1. Final R=0.024 8(wR=0.078 5). Complex 2 belongs to orthorhombic system, space group Pbca with unit cell dimensions a=1.144 94(19) nm, b=1.209 69(6) nm, c=1.740 73(8) nm and Z=8. Final R=0.018 5(wR=0.034 8). Both the two complexes are coordination polymers with a two-dimensional infinite structure, the repeat unit is [Cd 2(C 10H 2O 8)(H 2O) 6] (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] (2) which are bridged by the ligands of 1,2,4,5-benzenetetracarboxyl(C 10H 2O 8) and nicotinato(NA), respectively. The two polymers show strong fluorescence with λ em=433 nm(λ ex=333 nm, 1) and λ em=423 nm(λ ex=330 nm, 2) in the solid state at room temperature. The emissions observed in the polymers are tentatively assigned to the ligands fluorescence(LLCT).
