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
Kinetic analysis of removal of three rare earth elements metals, Ce, Sm, and Ybions from aqueous solutions in a continuous flow fixed bed reactor using Dowex 50 W-X8 ion-exchange resin was conducted. The performance o...Kinetic analysis of removal of three rare earth elements metals, Ce, Sm, and Ybions from aqueous solutions in a continuous flow fixed bed reactor using Dowex 50 W-X8 ion-exchange resin was conducted. The performance of the fixed bed sorption was evaluated using the concept of the sorption breakthrough process. Parameters characteristic of a fixed bed sorption such as breakthrough times,saturation times, critical reactor lengths, and lengths of mass transfer zone were inferred from the metal ion concentration breakthrough curves. The sorption capacity of Dowex 50 W-X8 ion-exchange resin for Ce3+, Sm3+, and Yb3+ are 191, 252, and 294 mg/g, respectively. The sorption kinetics were evaluated using a zero-order, first-order and second-order reaction models. The kinetics of the sorption process follows a zero-order model which has not been reported before. The rate constants of sorption using the zero-order kinetic model are obtained. Two different analysis were conducted to identify whether the diffusion is intraparticle or film diffusion. Both analysis confirms that the film diffusion is the controlling mechanism in reactor bed.展开更多
A series of novel ladder-type poly(azomethine amide)s (PAMs) were prepared from new azomethine containing carboxylic acid monomer (TCA) with simple aromatic diamines and aromatic diamines with thiourea groups (TDAs) b...A series of novel ladder-type poly(azomethine amide)s (PAMs) were prepared from new azomethine containing carboxylic acid monomer (TCA) with simple aromatic diamines and aromatic diamines with thiourea groups (TDAs) by means of phosphorylation polycondensation reaction. Molecular weights of the polyamides were evaluated viscometrically, and the inherent viscosities were in the range of 0.31 - 0.58 g/dl. These ladder-type polymers were not freely soluble in common organic solvents. Structure of monomers and polymers were confirmed using FT-IR, 1H-NMR and 13C-NMR spectroscopic analysis. Removal of Cu2+ and Cd2+ from aqueous solutions by adsorption onto the polyamides was investigated. The effect of pH, initial metal ion concentrations and contact time were studied in batch experiments. The polyamides were found to be highly effective adsorbents for the removal of Cu2+ and Cd2+ metal ions from aqueous solutions. In a mixture of metal ions, the selectivity order was found to be Pb(II) > Cu(II) > Cr(IV) > Cd(II).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.
文摘Kinetic analysis of removal of three rare earth elements metals, Ce, Sm, and Ybions from aqueous solutions in a continuous flow fixed bed reactor using Dowex 50 W-X8 ion-exchange resin was conducted. The performance of the fixed bed sorption was evaluated using the concept of the sorption breakthrough process. Parameters characteristic of a fixed bed sorption such as breakthrough times,saturation times, critical reactor lengths, and lengths of mass transfer zone were inferred from the metal ion concentration breakthrough curves. The sorption capacity of Dowex 50 W-X8 ion-exchange resin for Ce3+, Sm3+, and Yb3+ are 191, 252, and 294 mg/g, respectively. The sorption kinetics were evaluated using a zero-order, first-order and second-order reaction models. The kinetics of the sorption process follows a zero-order model which has not been reported before. The rate constants of sorption using the zero-order kinetic model are obtained. Two different analysis were conducted to identify whether the diffusion is intraparticle or film diffusion. Both analysis confirms that the film diffusion is the controlling mechanism in reactor bed.
文摘A series of novel ladder-type poly(azomethine amide)s (PAMs) were prepared from new azomethine containing carboxylic acid monomer (TCA) with simple aromatic diamines and aromatic diamines with thiourea groups (TDAs) by means of phosphorylation polycondensation reaction. Molecular weights of the polyamides were evaluated viscometrically, and the inherent viscosities were in the range of 0.31 - 0.58 g/dl. These ladder-type polymers were not freely soluble in common organic solvents. Structure of monomers and polymers were confirmed using FT-IR, 1H-NMR and 13C-NMR spectroscopic analysis. Removal of Cu2+ and Cd2+ from aqueous solutions by adsorption onto the polyamides was investigated. The effect of pH, initial metal ion concentrations and contact time were studied in batch experiments. The polyamides were found to be highly effective adsorbents for the removal of Cu2+ and Cd2+ metal ions from aqueous solutions. In a mixture of metal ions, the selectivity order was found to be Pb(II) > Cu(II) > Cr(IV) > Cd(II).
