This work reports synthesis and characterization of heterocyclic functionalized polymers, poly（triazole-etherimidazole）s（PTAEI）, from a dialkyne-terminated compound, 3-（4,5-bis（4-（propargyloxy）phenyl）-1H-imid...This work reports synthesis and characterization of heterocyclic functionalized polymers, poly（triazole-etherimidazole）s（PTAEI）, from a dialkyne-terminated compound, 3-（4,5-bis（4-（propargyloxy）phenyl）-1H-imidazol-2-yl）-9-ethyl-9H-carbazole, by using click reaction. PTAEIs were characterized and their properties such as solubility, thermal, mechanical, photophysical and metal ions adsorption were investigated. These polymers had weight average molar masses（Mw） in the range of 19100-26700 g/mol, exhibited excellent solubility in polar aprotic solvents and formed low-colored flexible thin films by solution casting method. They exhibited good thermal stability with glass transition temperatures（Tg） between 160 °C and 211 °C and 10% weight loss temperatures（T10%） in the range of 308-426 °C. Nanocomposites of PTAEIs with epoxide-terminated Fe3O4 showed that strong interfacial interaction between inorganic particles and the polymer matrix contributed to the enhanced thermal and mechanical properties. The photoluminescence intensity of the PTAEIs increased and the spectra red shifted with increasing Fe3O4 content. The PTAEIs and nanocomposites were tested for their extraction capability of metal ions from aqueous solutions either individually or in the mixture.展开更多
The occurrence of antibiotics in the environment has recently raised serious concerns regarding their potential threat to human health and aquatic ecosystem. A new magnetic nanocomposite, Fe304@C （Fe304 coated with c...The occurrence of antibiotics in the environment has recently raised serious concerns regarding their potential threat to human health and aquatic ecosystem. A new magnetic nanocomposite, Fe304@C （Fe304 coated with carbon）, was synthesized, characterized, and then applied to remove five commonly-used sulfonamides （SAs） from water. Due to its combinational merits of the outer functionalized carbon shell and the inner magnetite core, Fe3O4@C exhibited a high adsorption affinity for selected SAs and a fast magnetic separability. The adsorption kinetics of SAs on Fe304 @ C could be expressed by the pseudo second-order model. The adsorption isotherms were fitted well with the Dual-mode model, revealing that the adsorption process consisted of an initial partitioning stage and a subsequent hole-filling stage. Solution pH exerted a strong impact on the adsorption process with the maximum removal efficiencies （74% to 96%） obtained at pH 4.8 for all selected SAs. Electrostatic force and hydrogen bonding were two major driving forces for adsorption, and electron-donor-acceptor interactions may also make a certain contribution. Because the synthesized Fe304@C showed comprehensive advantages of high adsorptivity, fast magnetic separability, and prominent reusability, it has potential applications in water treatment.展开更多
Chlorophenols, typically 4-chlorophenols are highly toxic and non-biodegradable organic contaminants which pose serious threat to the environment, particularly when released into aqueous medium. The removal of these p...Chlorophenols, typically 4-chlorophenols are highly toxic and non-biodegradable organic contaminants which pose serious threat to the environment, particularly when released into aqueous medium. The removal of these pollutants by efficient method has received worldwide concern in recent past. A new Fe3O4–Cr2O3 magnetic nanocomposite was synthesized by wet chemical method under ultrasonic irradiation. Microstructure and morphology of the nanocomposite were characterized by powder X-ray diffraction（XRD）,Fourier transform infrared（FT-IR）, and a transmission electron microscope（TEM）. Magnetic and optical properties were studied by a vibrating sample magnetometer（VSM） and an ultraviolet–visible（UV–Vis） spectrophotometer respectively. The magnetic nanocomposite（MNC） was used as photocatalyst for effective decomposition of 4-chlorophenol in water under ultraviolet（UV） irradiation.展开更多
文摘This work reports synthesis and characterization of heterocyclic functionalized polymers, poly（triazole-etherimidazole）s（PTAEI）, from a dialkyne-terminated compound, 3-（4,5-bis（4-（propargyloxy）phenyl）-1H-imidazol-2-yl）-9-ethyl-9H-carbazole, by using click reaction. PTAEIs were characterized and their properties such as solubility, thermal, mechanical, photophysical and metal ions adsorption were investigated. These polymers had weight average molar masses（Mw） in the range of 19100-26700 g/mol, exhibited excellent solubility in polar aprotic solvents and formed low-colored flexible thin films by solution casting method. They exhibited good thermal stability with glass transition temperatures（Tg） between 160 °C and 211 °C and 10% weight loss temperatures（T10%） in the range of 308-426 °C. Nanocomposites of PTAEIs with epoxide-terminated Fe3O4 showed that strong interfacial interaction between inorganic particles and the polymer matrix contributed to the enhanced thermal and mechanical properties. The photoluminescence intensity of the PTAEIs increased and the spectra red shifted with increasing Fe3O4 content. The PTAEIs and nanocomposites were tested for their extraction capability of metal ions from aqueous solutions either individually or in the mixture.
基金supported by the National Natural Science Foundation of China(No.51221892)the Ministry of Science and Technology of China(No.2012AA062606,2012BAJ25B04)the People Programme(Marie CurieActions) of the European Union’s Seventh Programme FP7/2007-2013 under a REA grant(No.318926)
文摘The occurrence of antibiotics in the environment has recently raised serious concerns regarding their potential threat to human health and aquatic ecosystem. A new magnetic nanocomposite, Fe304@C （Fe304 coated with carbon）, was synthesized, characterized, and then applied to remove five commonly-used sulfonamides （SAs） from water. Due to its combinational merits of the outer functionalized carbon shell and the inner magnetite core, Fe3O4@C exhibited a high adsorption affinity for selected SAs and a fast magnetic separability. The adsorption kinetics of SAs on Fe304 @ C could be expressed by the pseudo second-order model. The adsorption isotherms were fitted well with the Dual-mode model, revealing that the adsorption process consisted of an initial partitioning stage and a subsequent hole-filling stage. Solution pH exerted a strong impact on the adsorption process with the maximum removal efficiencies （74% to 96%） obtained at pH 4.8 for all selected SAs. Electrostatic force and hydrogen bonding were two major driving forces for adsorption, and electron-donor-acceptor interactions may also make a certain contribution. Because the synthesized Fe304@C showed comprehensive advantages of high adsorptivity, fast magnetic separability, and prominent reusability, it has potential applications in water treatment.
基金support from Central Instruments Facility and Department of Chemistry of Indian Institute of Technology Guwahati for extending various analytical facilities during the course of investigation
文摘Chlorophenols, typically 4-chlorophenols are highly toxic and non-biodegradable organic contaminants which pose serious threat to the environment, particularly when released into aqueous medium. The removal of these pollutants by efficient method has received worldwide concern in recent past. A new Fe3O4–Cr2O3 magnetic nanocomposite was synthesized by wet chemical method under ultrasonic irradiation. Microstructure and morphology of the nanocomposite were characterized by powder X-ray diffraction（XRD）,Fourier transform infrared（FT-IR）, and a transmission electron microscope（TEM）. Magnetic and optical properties were studied by a vibrating sample magnetometer（VSM） and an ultraviolet–visible（UV–Vis） spectrophotometer respectively. The magnetic nanocomposite（MNC） was used as photocatalyst for effective decomposition of 4-chlorophenol in water under ultraviolet（UV） irradiation.
