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1.
Terpolymers (2,4‐DHPBF) were synthesized by the condensation of 2,4‐dihydro‐xypropiophenone, biuret, and formaldehyde in the presence of acid catalyst with varying the molar ratio of reacting monomers. Terpolymer composition has been determined on the basis of their elemental analysis and their number–average molecular weight of these resin were determined by conductometric titration in nonaqueous medium. The viscosity measurements were carried out in N,N‐dimethyl formamide which indicate normal behavior. IR spectra were studied to elucidate the structure. The terpolymer resin has been further characterized by UV–visible and 1H‐NMR spectra. The newly synthesized terpolymers proved to be selective chelating ion‐exchange terpolymers for certain metals. The chelating ion‐exchange properties of this terpolymer was studied for Fe (III), Cu (II), Hg (II), Cd (II), Co (II), Zn (II), Ni (II), and Pb (II) ions. A batch equilibrium method was employed in the study of the selectivity of metal ion uptake involving the measurement of the distribution of a given metal ion between the terpolymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The terpolymer showed a higher selectivity for Fe (III), Hg (II), Cd (II), and Pb (II) ions than for Cu (II), Co (II), Zn (II), and Ni (II) ions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

2.
A novel terpolymer involving 2‐amino‐6‐nitrobenzothiazole and ethylenediamine with formaldehyde was synthesized by a polycondensation technique using glacial acetic acid as a reaction medium. The resulting chelating terpolymer resin was characterized using elemental analysis, physicochemical parameters, and UV‐visible, Fourier transform infrared, 1H NMR and 13C NMR spectral studies. Average molecular weights of the terpolymer were determined using gel permeation chromatography. The surface morphology and the nature of the terpolymer were investigated using scanning electron microscopy and X‐ray diffraction. The chelation ion‐exchange property of the terpolymer was determined against some common metal ions such as Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+ using the batch equilibrium method. Effects of parameters such as the pH, contact time and various electrolyte concentrations were studied. The reusability of the terpolymer was checked in terms of its effective repeated usage. The results of the Langmuir and Freundlich adsorption isotherm models were best fitted with each other and the reaction kinetics followed pseudo second‐order kinetics. The terpolymer showed good results against Fe3+, Cu2+ and Ni2+ ions compared to those against the other metal ions. © 2014 Society of Chemical Industry  相似文献   

3.
The sorption properties of the commercially available cationic exchange resin, Amberlite IRC‐718, that has the iminodiacetic acid functionality, toward the divalent metal‐ions, Fe2+, Cu2+, Zn2+, and Ni2+ were investigated by a batch equilibration technique at 25°C as a function of contact time, metal ion concentration, mass of resin used, and pH. Results of the study revealed that the resin exhibited higher capacities and a more pronounced adsorption toward Fe2+ and that the metal‐ion uptake follows the order: Fe2+ > Cu2+> Zn2+ >Ni2+. The adsorption and binding capacity of the resin toward the various metal ions investigated are discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

4.
Hydrogels based on N‐acryloyl‐N′‐methylpiperazine (AcrNMP) swelled extensively in solutions of low pH due to the protonation of the tertiary amine. The water transport in the gels under an acidic condition was non‐Fickian and nearly Fickian in neutral pH with the collective diffusion coefficients determined as 2.08 × 10−7 and 5.00 × 10−7 cm−2 s−1, respectively. These gels demonstrated good metal‐uptake behavior with various divalent metal ions, in particular, copper and nickel, with the uptake capacity increased with increasing pH. The swelling ratio of the gel in the presence of metal ions decreased with increasing metal ion uptake. The results suggest that high metal ion uptake can lead to physical crosslinking arising from the interchain metal complex formation. The metal‐loaded gels could be stripped easily with 1M H2SO4 without any loss in their uptake capacity. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 268–273, 2001  相似文献   

5.
A novel polymeric ligand having 2,2′:6′,2″‐terpyridine as pendant group was prepared through a Williamson type etherification approach for the reaction between 4′‐hydroxy‐2,2′: 6′,2″‐terpyridine and the commercially available 4‐chloromethyl polystyrene. The chelating properties of the new polymer toward the divalent metal ions (Cu2+, Zn2+, Ni2+, and Pb2+) in aqueous solutions was studied by a batch equilibration technique as a function of contact time, pH, mass of resin, and concentration of metal ions. The amount of metal‐ion uptake of the polymer was determined by using atomic absorption spectrometry. Results of the study revealed that the resin exhibited higher capacities and a more pronounced adsorption toward Pb2+ and that the metal‐ion uptake follows the order: Pb2+ > Cu2+ > Zn2+ > Ni2+. The adsorption and binding capacity of the resin toward the various metal ions investigated are discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

6.
The changes in microstructural parameters in hydroxypropyl methylcellulose (HPMC) polymer films irradiated with 8 MeV electron beam have been studied using wide‐angle X‐ray scattering (WAXS) method. The crystal imperfection parameters such as crystal size <N>, lattice strain (g in %), and enthalpy (α*) have been determined by line profile analysis (LPA) using Fourier method of Warren. Exponential, Lognormal, and Reinhold functions for the column length distributions have been used for the determination of these parameters. The goodness of the fit and the consistency of these results suggest that the exponential distribution gives much better results, even though lognormal distribution has been widely used to estimate the similar stacking faults in metal oxide compounds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

7.
The chelation behavior of poly(β‐diketone), polymer I, and poly(β‐diketone) oxime, polymer II, toward the divalent metal ions, Cu2+, Zn2+, Ni2+, and Cd2+, and the trivalent lanthanide metal ions, La3+, Nd3+, Sm3+, Gd3+, and Tb3+ was investigated by a batch equilibration technique as a function of contact time, pH, and counter ion. Polymer II exhibited improved chelation characteristics toward lanthanide metal ions in comparison with polymer I and the metal‐ion uptake follows the order Tb3+ ≈ Gd3+ ≈ Sm3+ > Nd3+ ≈ La3+. On the other hand, polymer I showed relatively higher capacity than polymer II, toward the investigated divalent metal ions, where the metal‐ion uptake follows the order Cu2+ > Cd2+ ≈ Zn2+ > Ni2+. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

8.
Temperature‐responsive polymers have become increasingly attractive as carrier for the injectable drug delivery systems. In the present work, we have studied the preparation of poly(N‐isopropylacrylamide‐acrylamide‐vinilpyrrolidone) (NIPAAm‐AAm‐VP terpolymer) nanoparticulated terpolymer and its blend with poly(lactide‐co‐glycolide, PLGA; molar ratio of lactide/glycolid 1/3). Thermosensitive terpolymer, poly(NIPAAm‐AAm‐VP) was prepared by free‐radical polymerization in aqueous solution. The nanoparticles of poly(NIPAAm‐AAm‐VP) and its blend with PLGA containing naltrexone were prepared using the evaporation and w/o emulsion‐solvent evaporation methods, respectively. Nanoparticles prepared from terpolymer‐PLGA blend at low polymer concentration (5%) shows larger particle size (>300 nm) and higher drug content%. Various types of nanoparticles showed a burst release of less than 10% after 24 h . The results suggest that by regulating different variables, desired release profiles of naltrexone can be achieved using a blend of PLGA‐poly(NIPAAm‐AAm‐VP) nanoparticulate system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

9.
The aim of this study is to investigate in detail the feasibility of poly(2‐hydroxyethyl methacrylate‐N‐methacryloyl‐(L )‐histidine methyl ester), PHEMAH membranes for purification of immunoglobulin G (IgG) from human plasma. PHEMAH membranes were prepared by photo‐polymerization technique. Then, Zn2+, Ni2+, Co2+, and Cu2+ ions were chelated directly on the PHEMAH membranes. Elemental analysis assay was performed to determine the nitrogen content and polymerized MAH was calculated as 168.5 μmol/g. The nonspecific IgG adsorption onto the plain PHEMA membranes was negligible (about 0.25 mg/mL). A remarkable increase in the IgG adsorption capacities were achieved from human plasma with PHEMAH membranes (up to 68.4 mg/mL). Further increase was observed with the metal‐chelated PHEMAH membranes (up to 118 mg/mL). The metal‐chelate affinity membranes allowed the one‐step separation of IgG from human plasma. The binding range of metal ions for surface histidines from human plasma followed the order: Cu2+ > Ni2+ > Zn2+ > Co2+. Adsorbed IgG was eluted using 250 mM EDTA with a purity of 94.1%. IgG molecules could be repeatedly adsorbed and eluted with the metal‐chelated PHEMAH membranes without noticeable loss in their IgG adsorption capacity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
The diazonium salts of aniline and 4,4′‐diaminodiphenylmethane coupled with phenol and resorcinol were condensed with formaldehyde in alkaline media to yield polymeric resins. These polymers were found to readily react with metal ions like Cu2+ and UO, forming polychelates. The azodyes, resins, and polychelates were characterized by several instrumental techniques such as elemental analysis, FTIR, 1H‐NMR, GPC, XRD, TG–DTG, and DSC studies. The chelating capacity of the resins toward Cu2+ and UO ions was studied by spectrophotometry. The extent of metal loading of the resins was studied by varying the time of contact, metal‐ion concentration, and pH of the reaction medium. The alkali and alkaline earth metal ions had little effect on the metal‐ion uptake behavior of the resins. The resin derived from the azodye of 4,4′‐diaminodiphenylmethane was found to be more efficient in removing the metal ions from solution than were the resins from aniline. The optimum conditions for effective separation of Cu2+ from UO were determined. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3128–3141, 2000  相似文献   

11.
In the presence of a Cinchona alkaloid‐based squaramide organocatalyst, the [3+2] cycloaddition of isatin‐derived azomethine ylides with maleimides proceeded readily, thus delivering the desired pyrrolidine‐fused spirooxindoles in 61–89% yields with >20:1 dr and 12 to >99 % ee. The absolute configuration of 5‐chloro‐1,5′‐dimethyl‐3′‐phenyl‐3′,3a′‐dihydro‐2′H‐spiro[indoline‐3,1′‐pyrrolo[3,4‐c]pyrrole]‐2,4′,6′(5′H,6a′H)‐trione was unambiguously determined by means of X‐ray single crystal structure analysis. The reaction mechanism was hypothesized to account for the enantioselective formation of 5‐chloro‐1,5′‐dimethyl‐3′‐phenyl‐3′,3a′‐dihydro‐2′H‐spiro[indoline‐3,1′‐pyrrolo[3,4‐c]pyrrole]‐2,4′,6′(5′H,6a′H)‐trione.

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12.
Novolac resin was modified with 3‐aminopropyltrimthoxysilane to obtain phenol‐formaldehyde‐aminopropylsiloxane resin (PF‐APS). Fourier transformation infra‐red spectra, thermogravimetric analysis, elemental analysis, and pH‐metric titration were used to characterize PF‐APS. Its chemical formula was suggested to be C14H12.49N0.1O2Si0.1. The resin shows high experimental metal ions uptake capacity within short time of equilibration. The metal capacity was determined by atomic absorption spectrometry to be 0.787 mEq Cu/g. Maximum separation efficiencies of Cu2+, Cr3+, and Ni2+ from aqueous solutions on PF‐APS were at pH 8.0 and time of stirring 60 min; 94.0%, 90.8%, 83.2%, respectively. No significant interference from the background ions Na+, Cl?, and was observed on the separation process. The heavy metal ions were eluted using 0.01 mol L?1 EDTA at 65°C releasing >94% of the separated metal ions. The method of separation was applied successfully to remove the heavy metal ions Cu2+, Cr3+, and Ni2+ from electroplating wastewater from Dekirnis, Dakahlia Governorate, Egypt. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40993.  相似文献   

13.
The metal‐ion complexation behavior and catalytic activity of 4 mol % N,N′‐methylene bisacrylamide crosslinked poly(acrylic acid) were investigated. The polymeric ligand was prepared by solution polymerization. The metal‐ion complexation was studied with Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) ions. The metal uptake followed the order: Cu(II) > Cr(III) > Mn(II) > Co(II) > Fe(III) > Zn(II) > Ni(II). The polymeric ligand and the metal complexes were characterized by various spectral methods. The catalytic activity of the metal complexes were investigated toward the hydrolysis of p‐nitrophenyl acetate (NPA). The Co(II) complexes exhibited high catalytic activity. The kinetics of catalysis was first order. The hydrolysis was controlled by pH, time, amount of catalyst, and temperature. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 272–279, 2004  相似文献   

14.
Graft copolymerization of acrylic acid (AA) onto starch was carried out with ceric ammonium nitrate as initiator under nitrogen atmosphere. The grafting percentages (GP%) of starch‐graft‐acrylic acid (St‐g‐AA) copolymers were determined. The effect of GP% of St‐g‐AA copolymers on the competitive removal of Co2+, Ni2+, Zn2+ ions from aqueous solution was investigated at different pH (2, 4, 6). The concentrations of each ion in aqueous solution 5 mmol/L. Effects of various parameters such as treatment time, initial pH of the solution and grafting percentage of starch graft copolymers were investigated. Metal ion removal capacities of St‐g‐AA copolymers increased with GP% of the copolymers and pH. The results show that the removal of metal ions followed as given in the order Co2+ > Ni2+ > Zn2+. In this study, metal ion removal capacities were determined by atomic absorption spectrophotometer (AAS). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

15.
New 3rd generation designer ansa‐ruthenium(II) complexes featuring N,C‐alkylene‐tethered N,N‐dialkylsulfamoyl‐DPEN/η6‐arene ligands, exhibited good catalytic performance in the asymmetric transfer hydrogenation (ATH) of various classes of (het)aryl ketones in formic acid/triethylamine mixture. In particular, benzo‐fused cyclic ketones furnished 98 to >99.9% ee using a low catalyst loading.

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16.
Poly(2‐acrylamido glycolic acid‐co‐2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) [P(AGA‐co‐APSA)] was synthesized by radical polymerization in an aqueous solution. The water‐soluble polymer, containing secondary amide, hydroxyl, carboxylic, and sulfonic acid groups, was investigated, in view of their metal‐ion‐binding properties, as a polychelatogen with the liquid‐phase polymer‐based retention technique under different experimental conditions. The investigated metal ions were Ag+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+, and Cr3+, and these were studied at pHs 3, 5, and 7. P(AGA‐co‐APSA) showed efficient retention of all metal ions at the pHs studied, with a minimum of 60% for Co(II) at pH 3 and a maximum close to 100% at pH 7 for all metal ions. The maximum retention capacity (n metal ion/n polymer) ranged from 0.22 for Cd2+ to 0.34 for Ag+. The antibacterial activity of Ag+, Cu2+, Zn2+, and Cd2+ polymer–metal complexes was studied, and P(AGA‐co‐APSA)–Cd2+ presented selective antibacterial activity for Staphylococcus aureus with a minimum inhibitory concentration of 2 μg/mL. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
The complexation of copper (Cu2+), cobalt (Co2+), and cadmium (Cd2+) ions with poly(N‐vinylimidazole) (PVIm) and its protonated form in aqueous solution was studied conductometrically and viscometrically. From the conductometric and viscometric curves, it was found that four imidazole units were coordinated with one metal ion in the complex systems. Both studies showed that the complex formation tendency decreased in the following order: Cu2+ > Co2+ > Cd2+. Complex properties of metal ions with imidazole group were explained by referring to Pearson's treatment, as hard and soft acids and bases. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 376–384, 2002  相似文献   

18.
Treatment of N,2‐diarylacrylamides with the organoiodine(III) compound phenyliodine(III) bis(2,2‐dimethylpropanoate) [PhI(O2C‐t‐Bu)2] and boron trifluoride etherate (BF3⋅Et2O) resulted in a direct and selective oxidative C(sp2)−C(sp2) bond formation leading to a convenient assemblage, under mild conditions, of the biologically important 3‐arylquinolin‐2‐one skeleton. Differing from the five‐membered oxindole products from oxidative cyclizations mediated by transition metals, this metal‐free approach realized a direct annulation of the N‐arylacrylamide into a six‐membered 3‐arylquinolin‐2‐one skeleton.

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19.
A series of novel fluorine‐containing cyclooxygenase‐2 (COX‐2) inhibitors was designed and synthesized based on the previously reported fluorescent COX‐2 imaging agent celecoxib–NBD ( 3 ; NBD=7‐nitrobenzofurazan). In vitro COX‐1/COX‐2 inhibitory data show that N‐(4‐fluorobenzyl)‐4‐(5‐p‐tolyl‐3‐trifluoromethylpyrazol‐1‐yl)benzenesulfonamide ( 5 ; IC50=0.36 μM , SI>277) and N‐fluoromethyl‐4‐(5‐p‐tolyl‐3‐trifluoromethylpyrazol‐1‐yl)benzenesulfonamide ( 6 ; IC50=0.24 μM , SI>416) are potent and selective COX‐2 inhibitors. Compound 5 was selected for radiolabeling with the short‐lived positron emitter fluorine‐18 (18F) and evaluated as a positron emission tomography (PET) imaging agent. Radiotracer [18F] 5 was analyzed in vitro and in vivo using human colorectal cancer model HCA‐7. Although radiotracer uptake into COX‐2‐expressing HCA‐7 cells was high, no evidence for COX‐2‐specific binding was found. Radiotracer uptake into HCA‐7 tumors in vivo was low and similar to that of muscle, used as reference tissue.  相似文献   

20.
A novel class of polymer–metal complexes was prepared by the condensation of a polymeric ligand with transition‐metal ions. The polymeric ligand was prepared by the addition polymerization of thiosemicarbazides with toluene 2,4‐diisocyanate in a 1 : 1 molar ratio. The polymeric ligand and its polymer–metal complexes were characterized by elemental analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, and 13C‐NMR and 1H‐NMR spectroscopy. The geometries of the central metal ions were determined by electronic spectra (UV–visible) and magnetic moment measurement. The antibacterial activities of all of the synthesized polymers were investigated against Bacillus subtilis and Staphylococcus aureus (Gram positive) and Escherichia coli and Salmonella typhi (Gram negative). These compounds showed excellent antibacterial activities against these bacteria with the spread plate method on agar plates, and the number of viable bacteria were counted after 24 h of incubation period at 37°C. The antibacterial activity results revealed that the Cu(II) chelated polyurea showed a higher antibacterial activity than the other metal‐chelated polyureas. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

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