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1.
Pd(II), Pt(II) and Ag(I) ions were found to form stable complexes with 4-(p-tolyl)- or 4-ethyl-1-(pyridin-2-yl)thiosemicarbazides (Hp-TPTS or HEPTS). The complex structure was elucidated by analysis (elemental and thermal), spectroscopy (electronic, IR and 1H NMR spectra) and physical measurements (magnetic susceptibility and molar conductance). The ligands coordinate to the metal ions as monobasic bidentate through nitrogen and sulfur atoms. The electronic spectra of the Pt(II) complexes in DMF showed a metal to ligand charge transfer transition at 11,935–13,260 cm?1. The structural, electronic and vibrational features of HEPTS and Hp?TPTS were discussed on the basis of semi-empirical quantum mechanic calculations [ZINDO/S and semi-empirical parameterization (PM3)]. The simulated IR and electronic spectra are found reasonable in accordance with the experimental data. Finally, the antibacterial activities of the ligands and their complexes were investigated and some were found promising.  相似文献   

2.
In this paper linseed oil based metallopolyesteramides (Mn(II)-/Co(II)-/Cu(II)-LPEA) containing metals [with half filled (d 5) and partially filled (d 7 and d 9) d orbitals] were synthesized via green route for the application of eco-friendly protective green material. This paper also described the role of occupancy of d orbitals on the performance of such polymers. The synthesis reaction was carried out in situ through condensation polymerization among linseed fatty amide diol (HELA), phthalic anhydride and respective metal acetates [M (OCOCH3)2; M = Mn(II), Co(II), Cu(II); different mole ratios] in absence of any harmful organic solvent. The structural determination (FTIR, 1H-NMR and 13C-NMR), curing, thermal, physico-chemical, physico-mechanical, anticorrosive/chemical resistance, antibacterial properties of Mn(II)-/Co(II)-/Cu(II)-LPEA were carried out. The curing mechanism of the resin was confirmed by the comparison of FTIR spectra of uncured and cured resin. The curing mechanism of Mn(II)-/Co(II)-/Cu(II)-LPEA is found to be contrary to that of reported oil based polymer that involves the lipid autoxidation (slow process) in which driers are required to speed up the room temperature curing process. The incorporation of metals in Mn(II)-/Co(II)-/Cu(II)-LPEA improved the thermal stability as compared to virgin linseed oil based polyesteramide (LPEA). Mn(II)-/Co(II)-/Cu(II)-LPEA also show excellent antibacterial performance against Staphylococcus aureus and Escherichia coli. The observed diversity in material properties suggests that Mn-LPEA may be useful as an eco-friendly protective green material with thermal stability up to 320–330 °C.  相似文献   

3.
Different types of chelated polymer complexes have been synthesized to obtain improved electrical properties. Compact discs from powders of the chelated polymers were prepared and heated in a specially designed holder. Electrical conductivity and dielectric constant of Cu(II) and Ni(II): N-salicylidene polymethacrylic acid hydrazide samples were measured at a fixed frequency (1600 Hz) throughout the temperature range 25-150°C. The AC conductivity as well as dielectric measurements showed maxima at 85°C. The water molecules which were trapped in the polymer matrix are believed to play the main role in conduction and dielectric behaviour of the polymeric material. From the AC conductance and dielectric constant measurements, the dielectric losses of these polymeric materials were calculated as a function of temperature.  相似文献   

4.
Summary A novel polymer having β,β-triketone unit in the main chain was prepared by polycondensation of triethylene glycol bis(p-butoxycarbonylphenyl) ether (1) with triethylene glycol bis(p-acetylacetophenyl) ether (4). The obtained polymer was soluble in CHCl3, DMF, and DMSO. The structure of the polymer was confirmed by 1H-NMR. Insoluble brownish yellow copper (II) chelate was obtained by adding a methanol solution of copper (II) acetate to a chloroform solution of the polymer. The IR analysis and the measurement of copper content by iodometric titration showed the quantitative formation of binuclear copper (II) complex. Received: 20 March 1998/Accepted: 17 April 1998  相似文献   

5.
The polymer poly(vinylidene fluoride) (PVDF) was irradiated with X-rays produced by a nonmonochromatic (MgKα) source and the structural and electronic PVDF surface modifications were studied by X-ray photoelectron spectroscopy (XPS). Changes in the shape and intensity of the C1s and F1s lines show that a PVDF degradation consisting of the polymer defluorination takes place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:2125–2129, 1998  相似文献   

6.
New polymeric structures obtained by chemical transformations of maleic anhydride/dicyclopentadiene copolymer with triethylenetetraamine, p‐aminobenzoic acid, and p‐aminophenylacetic acid were used for the removal Cu(II) ions from aqueous solutions. The experimental values prove the importance of the chelator nature and of the macromolecular chain geometry for the retention efficiency. The retention efficiency (ηr), the retention capacity (Q e ), and the distribution coefficient of the metal ion into the polymer matrix (K d ) are realized by evaluation of residual Cu(II) ions in the effluent waters, by atomic adsorption. Also are discussed the influence of pH, the thermal stability of the polymer, and their polymer–metal complex, as well as the particular aspects regarding the contact procedure and the batch time. Based on the polymers and polymer–metal complexes characterization a potential retention mechanism is proposed. All polymer supports as well theirs metal–complexes are characterized by ATD and FTIR measurements. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1397–1405, 2007  相似文献   

7.
In Part I of the present article predictions of the polymer–filler gel formation theory were tested experimentally using fine-particle silica in natural rubber (NR) and in styrene–butadiene rubber (SBR). Part II brings a more detailed experiment–theory comparison using carbon blacks differing in specific surface area and structure, graphitized blacks, fume silica, and surface-modified (hydrophobized) fume silica. In the region of low and medium filler concentration c, the c-dependence of the fraction G of polymer in polymer–filler gel, of the fraction B of total filler-bound polymer, of the fraction wdisp of solvent-dispersed filler particles were found to be correctly predicted by the theory. The effect of filler characteristics and of the method of its incorporation into the polymer on the values of the adjustable parameters of the theory (filler surface adsorptivity, D, and filler particles connectivity, f) was determined and is discussed. In the region of very high c increasing positive deviations of D from the low-c behavior were observed and an explanation for this effect is proposed. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 95–107, 1998  相似文献   

8.
Summary The EPR spectra of composite dextran and carboxymethyldextran gels were studied in order to identify the functional groups involved in copper(II) complexation depending on pH. The porous structure resulting from crosslinking of polymer chains of dextran, via epichlorohydrin, forces the immobilization of Cu2+ ions surrounded by different oxygen groups of the polymer gel matrix. The different polynuclear structures are postulated to be formed depending on the type of polysaccharide derivatives. The results indicate that carboxyl and deprotonated hydroxyl groups participate in the complex formation. Received: 30 January 1998/Revised version: 13 May 1998/Accepted: 10 June 1998  相似文献   

9.
Poly(N-vinylimidazole) (PVIm) gels were prepared by irradiating a binary mixture of N-vinylimidazole (VIm)–water in a 60Co-γ source having 4.5 kGy/h dose rate. In the glucose oxidase (GOx) adsorption studies, affinity gels with a swelling ratio of 1100% for PVIm and 40 and 55% for Cu(II)- and Co(II)-chelated PVIm gels, respectively, at pH 6.5 in phosphate buffer were used. FTIR spectra were taken for PVIm and Cu(II)- and Co(II)-chelated PVIm, and glucose oxidase adsorption on these gels, to characterize the nature of the interactions in each species. The results show that PVIm–glucose oxidase interaction is mainly electrostatic and metal ion–chelated PVIm gel–glucose oxidase interaction is of coordinate covalent nature. Cu(II) and Co(II) ions were chelated within the gels via amine groups on the imidazole ring of the gel. Different amounts of Cu(II) and Co(II) ions [maximum 3.64 mmol/g dry gel for Cu(II) and 1.72 mmol/g dry gel for Co(II)] were loaded on the gels by changing the initial concentration of Cu(II) and Co(II) ions at pH 7.0. GOx adsorption on these gels from aqueous solutions containing different amounts of GOx at different pH was investigated in batch reactors. GOx adsorption capacity was further increased when Cu(II) and Co(II) ions were attached [up to 0.53 g GOx/g dry Co(II)-chelated PVIm gels]. More than 90% of the adsorbed GOx was desorbed in 5 h in desorption medium containing 1.0M KSCN at pH 7.0 for plain gel and 0.05M EDTA at pH 4.9 for metal-chelated gel. Nonspecific glucose oxidase adsorption on/in the metal ion–chelated PVIm gel was investigated using 0.02M of phosphate buffer solution. The nonspecific GOx adsorption was determined to be about 18% for PVIm and 8% for the metal ion–chelated PVIm gels. The ionic strength effect was investigated both on PVIm and on the metal ion–chelated PVIm gels for the glucose oxidase adsorption. It was found that ionic strength was more effective on the PVIm gel because of the electrostatic interaction between protonated gel and the deprotonated glucose oxidase side chain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 446–453, 2001  相似文献   

10.
Poly(2-hydroxyethyl methacrylate) [poly(HEMA)] membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (α-α′-azobis-isobutyronitrile, AIBN). The triazine dye Cibacron Blue F3GA was attached as an affinity ligand to poly(HEMA) membranes, covalently. These affinity membranes with a swelling ratio of 58% and containing 10.7 mmol Cibacron Blue F3GA/m2 were used in the albumin adsorption studies. After dye-attachment, Zn(II) ions were chelated within the membranes via attached-dye molecules. Different amounts of Zn(II) ions [650–1440 mg Zn(II)/m2] were loaded on the membranes by changing the initial concentration of Zn(II) ions and pH. Bovine serum albumin (BSA) adsorption on these membranes from aqueous solutions containing different amounts of BSA at different pH was investigated in batch reactors. The nonspecific adsorption of BSA on the poly(HEMA) membranes was negligible. Cibacron Blue F3GA attachment significantly increased the BSA adsorption up to 92.1 mg BSA/m2. Adsorption capacity was further increased when Zn(II) ions were attached (up to 144.8 mg BSA m2). More than 90% of the adsorbed BSA was desorbed in 1 h in the desorption medium containing 0.5M NaSCN at pH 8.0 and 0.025M EDTA at pH 4.9. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 657–664, 1998  相似文献   

11.
Poly[acrylamide-co-1-(2-hydroxyethyl)aziridine], obtained by spontaneous copolymerization, which contains different types of ligand groups as tertiary amines and hydroxyl and amide groups, was tested as a polychelatogen using the liquid-phase polymer-based retention (LPR) technique. The metal ion retention ability of this polymer was found to depend on the pH and it showed a high selectivity to copper(II) at pH 5. The maximum capacity of Cu(II) was determined at pH 5 by using the enrichment variant of LPR. The retention capacities of the polymer with Cu(II), Cd(II), Co(II), Cr(III), Ni(II), Pb(II), Zn(II), and Fe(II) were studied at different pH and the results are compared with those of branched polyethylenimine and poly[1-(2-hydroxyethyl)aziridine] homopolymers. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 817–824, 1998  相似文献   

12.
Polymer complexes with uranium, cobalt, and iron chlorides were synthesized and investigated by elemental analysis, electronic (uv–visible), IR vibration, and magnetic moment measurements. The thermal stabilities of N‐acryloyl,N′‐cyanoacetohydrazide (ACAH) homopolymers and polymer complexes of poly(ACAH) (PACAH) with metal chlorides were studied thermogravimetrically. The rates of polymerization of PACAH in the absence and presence of metal chlorides were studied. The activation energies of the degradation of the homopolymer and polymer complexes were calculated using the Arrhenius equation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3354–3358, 2003  相似文献   

13.
p‐Chlorophenylmaleimide and p‐hydroxyphenylmaleimide with 2‐hydroxypropyl methacrylate were synthesized by radical polymerization, and the metal ion retention capacity and thermal behavior of the copolymers were evaluated. The copolymers were obtained by solution radical polymerization with a 0.50 : 0.50 feed monomer ratio. The maximum retention capacity (MRC) for the removal of two metal ions, Co(II) and Ni(II) in aqueous phase were determined using the liquid‐phase polymer based retention technique. Inorganic ion interactions with the hydrophilic polymer were determined as a function of pH. The metal ion retention capacity does not depend strongly on the pH. Metal ion retention increased with an increase of pH for a copolymer composition 0.50 : 0.50. At different pH, the MRC of the poly(p‐chlorophenylmaleimide‐co‐2‐hydroxypropylmethacrylate) for Co(II) and Ni(II) ions varied from 44.1 to 48.6 mg/g and from 41.5 mg/g to 46.0 mg/g, respectively; while the MRC of poly(p‐hydroxyphenylmaleimide‐co‐2‐hydroxypropyl methacrylate) for Co(II) and Ni(II) ions varied from 28.4 to 35.6 mg/g and from 27.2 to 30.8 mg/g, respectively. The copolymers and copolymer–metal complexes were characterized by elemental analysis, FT‐IR, 1H NMR spectroscopy, and thermal behavior. The thermal behavior of the copolymer and polymer–metal complexes were studied using differential scanning calorimetry and thermogravimetry techniques under nitrogen atmosphere. The thermal decomposition temperature and Tg were influenced by the binding‐metal ion on the copolymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

14.
Four N-donors (PHDA, ATPH, APHO, and MTAN) containing NH2 were used to extract Hg(II), Cd(II), and Pb(II). Their extraction capacity was determined by measurement of percentage extraction.

The chelates extract these metals differently: for example, efficiency of ATPH was the highest for Hg(II) compared to PHDA, APHO, and MTAN.

The extraction efficiency was found to depend on: donor atom hardness, chelate total hardness, metal: chelate mole ratio and substituent’s electronic effects. Among all, total hardness and chelate stability are key factors and molecule of small (EHOMOELUMO) is more reactive, where extraction efficiency increases as molecular stability decreases.  相似文献   


15.
The synthesis of poly (N,N′-dimethylacrylamide-co-acrylic acd) under different feed molar ratios was carried out by radical polymerization. Both homopolymers were also synthesized to compare the metal ion binding abilities. All polymers were water-soluble and were characterized by FTIR, 1H-NMR, 13C-NMR, and TGA. The metal complexing properties for the metals Cu(II), Co(II), Ni(II), Cd(II), Zn(II), Pb(II), Hg(II), Cr(III), and Fe(III) in the aqueous phase were investigated using the liquid-phase polymer-based retention (LPR) method. The metal ion interactions with the hydrophilic polymer were determined as a function of pH and the filtration factor. According to the interaction pattern obtained, the metal ions form the most stable complexes with the copolymer poly(N,N′-dimethylacrylamide-co-acrylic acid) within the pH range 5–7. Hg(II) was not retained at all the pH ranges investigated. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 93–100, 1998  相似文献   

16.
This study describes the equilibrium, kinetics, and thermodynamics of the palladium(II) (Pd(II)) adsorption onto poly(m‐aminobenzoic acid) (p‐mABA) chelating polymer. The p‐mABA was synthesized by the oxidation reaction of m‐aminobenzoic acid monomer with ammonium peroxydisulfate (APS). The synthesized p‐mABA chelating polymer was characterized by FTIR spectroscopy, gel permeation chromatography (GPC), thermal analysis, potentiometric titration, and scanning electron microscopy (SEM) analysis methods. The effects of the acidity, temperature, and initial Pd(II) concentration on the adsorption were examined by using batch adsorption technique. The optimum acidity for the Pd(II) adsorption was determined as pH 2. In the equilibrium studies, it was found that the Pd(II) adsorption capacity of the polymer was to be 24.21 mg/g and the adsorption data fitted better to the Langmuir isotherm than the Freundlich isotherm. The kinetics of the adsorption fitted to pseudo‐second‐order kinetic model. In the thermodynamic evaluation of the adsorption, the Δ values were calculated as ?16.98 and ?22.26 kJ/mol at 25–55°C temperatures. The enthalpy (ΔH°), entropy (ΔS°), and the activation energy (Ea) were found as 35.40 kJ/mol, 176.05 J/mol K, and 61.71 kJ/mol, respectively. The adsorption of Pd(II) ions onto p‐mABA was a spontaneous, endothermic, and chemical adsorption process which is governed by both ionic interaction and chelating mechanisms. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42533.  相似文献   

17.
The commercial poly(vinyl acetate) bulk was studied by nuclear magnetic resonance (NMR) at solution and solid state to understand much better the behavior of this polymer to obtain information on structure, sample molecular mobility, and heterogeneity. To analyze the behavior of this polymer, we have chosen NMR techniques, such as carbon-13 solution, magic angle spinning, cross-polarization/magic angle spinning, proton spin-relaxation time in the rotating frame parameter (T1ρ), and dipolar dephasing experiment. Therefore, from the NMR response, poly(vinyl acetate) presents a random monomer sequence distribution along the macromolecule chains, and this provides microdomains with different mobilities. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2457–2461, 1998  相似文献   

18.
《Applied Clay Science》2007,35(1-2):31-38
Formation of three fluorescent complexes, Li(I)-, Zn(II)- and Mn(II)-8-hydroxyquinoline complexes (Mqn), was investigated in the interlayer spaces of montmorillonites by solid–solid reactions between homoionic (Li(I), Zn(II) and Mn(II)) montmorillonites and neat 8-hydroxyquinoline at room temperature. The intercalation of 8-hydroxyquinoline molecules into the interlayer spaces of Li(I)-, Zn(II)- and Mn(II)-montmorillonites was confirmed by powder XRD, FT-IR, TG-DTA and chemical analysis. The in-situ complex formation was proved by FT-IR, UV–vis, and photoluminescence spectroscopies. The absorption and luminescence bands of the complexes shifted slightly compared to the corresponding neat complexes, suggesting the different microstructures including molecular packing of the complexes in the interlayer spaces of montmorillonites as a result of host–guest interactions.  相似文献   

19.
To obtain an optical polymer with a high refractive index (nD) and Abbe's number (νD), a series of 1,4-dithiane-2,5-bis(thiomethyl) (DBT) group-bearing poly(S-alkylcarbamate) and polyvinylsulfide were synthesized by the polyaddition of 2,5-bis(mercaptomethyl)-1,4-dithiane (BMMD) with diisocyanates and by the addition polymerization of 2,5-bis(2-thia-3-butenyl)-1,4-dithiane (TBD) in bulk, respectively. Their nD : νD values, ranging from 1.598 : 38.2 to 1.678 : 34.8, are comparable to those of flint glass. Some of the polymers having a high transparency and glass transition temperature were suggested to be useful as optical polymers. The DBT group contribution to the increase of the nD value of the obtained polymer was explained in terms of the value defined by the ratio of molar refraction to molar volume and was concluded to be of primary importance because the value for the DBT group (0.38) was greater than that for the residual group making up the polymer structure. This group's contribution in preventing the degradation of the νD of the polymers was also discussed based on the UV spectrum of BMMD, which only showed a suppressed absorption band. BMMD and TBD are useful monomers for preparing an optical polymer with high nD and νD values. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1791–1799, 1998  相似文献   

20.
N‐2‐thiazolyl(meth)acrylamides were polymerized by a radical route to obtain polymers in good yields. The polymers, with a pendent heterocyclic group, are soluble in common organic solvents, which allow the corresponding metal complexes with higher loads to be prepared easily. FTIR, 1H NMR, and energy‐dispersive X‐Ray spectroscopy (EDX) were applied to characterize these materials. The magnetic behavior of poly(N‐2‐thiazolyl(meth)acrylamide)‐Fe(II) complexes was examined as a function of applied magnetic field at 4 K and as a function of temperature (4 ~ 300 K) at an applied magnetic field of 1 ~ 3 kOe, exhibiting the characteristics of a ferromagnet. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 83–87, 2005  相似文献   

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