首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
In this study, the water-soluble polymers of N-maleoyl glycine (MG) with crotonic acid (CA) were copolymerized by free radical polymerization to obtain hydrophilic polymers, in order to study the effect of the functional groups in the copolymers on the metal ion retention capacity, electrochemical and thermal behavior, since that important requirements for their use in technological applications are: high solubility in water, chemical stability, a high affinity for one or more metal ions, and selectivity for the metal ion of interest. The metal complexation properties of poly(MG-co-CA) for the metal ions were investigated at pH 3, 5, and 7 in aqueous solution. The metal ion investigated were: Cu(II), Co(II), Cr(III), Ni(II), Cd(II), Zn(II), and Fe(III). The polymeric systems showed high metal ion retention for Zn (II) and Fe(III) at different pH. At different pHs, the MRC of the poly(MG-co-CA) for Fe(III) ions varied from 122.1 to 146.2 mg/g and from 120.5 to 133.5 mg/g, (samples 1 and 2 at pH 3 and 7, respectively). The MRC had the highest retention values for both copolymer systems at pH 7. The copolymers presented higher thermal decomposition temperature (TDT) in comparison with copolymer–metal complexes at pH 3 and 5. The cyclic voltammetry (CV) for poly(MG-co-CA) (20 mM) was compared with the CV of the [poly(MG-co-CA)–Fe(III)] copolymer complex. Moreover, [poly(MG-co-CA)–Fe(III)] showed a redox wave difference between +0.25 and +0.50 V possibly due to the presence of metal complexed with the polymer. The electrochemical characterization of the copolymer poly(MG-co-AC) shown the reduction of carboxylic acid groups of the N-maleoylglycine and crotonic acid moiety to hydroxyl group. The results support the assumption that the copolymer presents convenient electroactivity.  相似文献   

2.
We carried out the free‐radical copolymerization of N‐phenylmaleimide with acrylic acid and acrylamide with an equimolar feed monomer ratio. We carried out the synthesis of the copolymers in dioxane at 70°C with benzoyl peroxide as the initiator and a total monomer concentration of 2.5M. The copolymer compositions were obtained by elemental analysis and 1H‐NMR spectroscopy. The hydrophilic polymers were characterized by elemental analysis, Fourier transform infrared spectroscopy, 1H‐NMR spectroscopy, and thermal analysis. Additionally, viscosimetric measurements of the copolymers were performed. Hydrophilic poly(N‐phenylmaleimide‐co‐acrylic acid) and poly(N‐phenylmaleimide‐co‐acrylamide) were used for the separation of a series of metal ions in the aqueous phase with the liquid‐phase polymer‐based retention method in the heterogeneous phase. The method is based on the retention of inorganic ions by the polymer in conjunction with membrane filtration and subsequent separation of low‐molecular‐mass species from the formed polymer/metal‐ion complex. The polymer could bind several metal ions, such as Cr(III), Co (II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) inorganic ions, in aqueous solution at pH values of 3, 5, and 7. The interaction of the inorganic ions with the hydrophilic polymer was determined as a function of pH and a filtration factor. Hydrophilic polymeric reagents with strong metal‐complexing properties were synthesized and used to separate those complexed from noncomplexed ions in the heterogeneous phase. The polymers exhibited a high retention capability at pH values of 5 and 7. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006  相似文献   

3.
The free‐radical copolymerization of water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) was carried out with a feed monomer ratio of 75:25 mol %, and the total monomer concentration was 2.67M. The synthesis of the copolymer was carried out in dioxane at 70°C with benzoyl peroxide as the initiator. The copolymer composition was obtained with elemental analysis and 1H‐NMR spectroscopy. The water‐soluble polymer was characterized with elemental analysis, Fourier transform infrared, 1H‐ and 13C‐NMR spectroscopy, and thermal analysis. Additionally, viscosimetric measurements of the copolymer were performed. The thermal behavior of the copolymer and its complexes were investigated with differential scanning calorimetry (DSC) and thermogravimetry techniques under a nitrogen atmosphere. The copolymer showed high thermal stability and a glass transition in the DSC curves. The separation of various metal ions by the water‐soluble poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) reagent in the aqueous phase with liquid‐phase polymer‐based retention was investigated. The method was based on the retention of inorganic ions by this polymer in a membrane filtration cell and subsequent separation of low‐molar‐mass species from the polymer/metal‐ion complex formed. Poly(1‐vinyl‐2‐pyrrolidone‐co‐hydroxyethylmethacrylate) could bind metal ions such as Cr(III), Co(II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) in aqueous solutions at pHs 3, 5, and 7. The retention percentage for all the metal ions in the polymer was increased at pH 7, at which the maximum retention capacity could be observed. The interaction of inorganic ions with the hydrophilic polymer was determined as a function of the pH and filtration factor. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 178–185, 2006  相似文献   

4.
A copolymer resin (p‐APDF) has been synthesized using the monomers p‐aminophenol, dithiooxamide, formaldehyde in 1 : 1 : 2M proportions in the presence of 2M HCl as catalyst. The structure of p‐APDF copolymer has been elucidated on the basis of elemental analysis and various physicochemical techniques, i.e., UV‐visible, FTIR, and 1H‐NMR spectroscopy. The number average molecular weight of copolymer resin was determined by nonaqueous conductometric titration in DMF. Viscosity measurement were carried out in DMF indicate normal behavior. The prepared resin proved to be a selective ion exchange resin for some metal ions. The chelating ion exchange properties of this resin was studied for Fe(III) and Cu(II), Ni(II), Co(II), Zn(II), Cd(II), Pb(II) ions. A batch equilibrium method was used to study selectivity of metal ion uptake over a wide pH range and in media of various ionic strength. The resin showed a higher selectivity for Fe(III), Ni(II), Cu(II) ions than for Co(II), Pb(II), Zn(II), and Cd(II) ions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

5.
This article reports the synthesis of poly(N‐maleoylglycine‐co‐itaconic acid) by radical copolymerization under different feed mole ratios and its properties to remove various metal ions, such as Cu(II), Cr(III), Co(II), Zn(II), Ni(II), Pb(II), Cd(II), and Fe(III), in aqueous phase with the liquid‐phase polymer‐based retention(LPR) technique. The interactions of inorganic ions with the hydrophilic water‐soluble polymer were determined as a function of pH and filtration factor. Metal ion retention was found to strongly depend on the pH. Metal ion retention increased as pH and MG content units in the macromolecular backbone increased. The copolymers were characterized by elemental analysis, FTIR, 1H‐NMR, and 13C‐NMR spectroscopy. Additionally, intrinsic viscosity, molecular weight, and polydispersity have been determined for the copolymers. Copolymer and polymer–metal complex thermal behavior was studied using differential scanning calorimetry (DSC) and thermogravimetry (TG) techniques under nitrogen atmosphere. The thermal decomposition temperatures (TDT) were influenced by the copolymer composition. The copolymers present lower TDT than the polymer–metal complex with the same copolymer composition. All copolymers present a single Tg, indicating the formation of random copolymers. A slight deviation of the Tg for the copolymers and its complexes can be observed. The copolymer Tg is higher than the Tg value for the polymer–metal complexes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

6.
Poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid), poly(methacrylic acid), and five copolymers of poly[(2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid)‐co‐(methacrylic acid)] were synthesized by radical polymerization and obtained in yields >97%. The polymers were characterized by FT‐IR, [1H]NMR, and [13C]NMR and studied by means of the Liquid‐phase Polymer‐based Retention (LPR) technique. The metal ion retention ability of the copolymers for Cu(II), Cd(II), Co(II), Hg(II), Ni(II), Zn(II), Cr(III) and Ag(I) was investigated at different pH values because of their environmental and analytical interest. The retention profiles of the copolymers were compared with those of the corresponding homopolymers and retention of metal ions was found to increase with increasing pH. © 2001 Society of Chemical Industry  相似文献   

7.
The macromonomer polyethylene glycol methylether methacrylate was homo‐ and copolymerized with 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid under three feed monomer ratios. The initiator used was ammonium peroxydisulfate (0.2 mol %). All the polymers were completely soluble in water. The copolymer composition was determined by elemental analysis. The metal ion interaction capability of the three polymers was investigated through the liquid‐phase polymer‐based retention (LPR) technique at different values of pH and filtration factor Z. The highest metal ion retention ability was observed at pH 5.0. The homopolymer showed a high selectivity for Ni(II) ions at pH 3.0. The copolymers (PEGMEM)1.51co‐(APSA)1.00 and (PEGMEM)1.00co‐(APSA)1.95 showed a high selectivity for Cr(III) ions at pH 3.0. The maximum retention capacity, in general, was similar for the homo‐ and copolymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2955–2960, 2004  相似文献   

8.
The synthesis of the water‐soluble poly(acrylic acid‐co‐vinylsulfonic acid) at different feed monomer ratios, while maintaining constant the total number of mol, was carried out by radical polymerization. The copolymers were characterized by FTIR and 1H‐NMR spectroscopies. The copolymer composition was determined by its sulfur content and by potentiometric titration. The metal ion binding properties for Ni(II) and Cu(II) in the aqueous phase were studied using the liquid‐phase polymer‐based retention (LPR) technique for two values of ionic strength. For comparison, the retention properties of both homopolymers were included. The complexing ability of the polymer was determined by the relative amount of carboxylic acid groups. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1698–1704, 2003  相似文献   

9.
Water‐soluble copolymers of N‐acryloyl‐N‐methylpiperazine and N‐acetyl‐α‐aminoacrylic acid were synthesized by radical polymerization. The copolymerization yield ranged between 60 and 97%. The FTIR and NMR spectra demonstrated that the copolymerization occurred. The copolymer composition was determined from 1H‐NMR spectra by comparison of methyl groups from both moieties. The copolymers were richest in AAA units. The metal ion retention properties were investigated by the liquid‐phase polymer‐based retention (LPR) technique at different pH and filtration factors. The affinity for the metal ions depended on the copolymer composition, pH, and filtration factor. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2556–2561, 2002  相似文献   

10.
BACKGROUND: The high‐technology industries have been the driving force in the development of new synthetic polymers that combine thermal stability with specific functional properties. In this study p‐chlorophenylmaleimide, p‐hydroxyphenylmaleimide and p‐nitrophenylmaleimide (R‐PhMI) with 2‐hydroxyethyl methacrylate (HEMA) were synthesized by free radical polymerization to obtain hydrophilic polymers, in order to study the effect of the p‐chloroaryl, p‐hydroxyaryl or p‐nitroaryl group on the copolymer composition, electrochemical behavior and thermal properties. RESULTS: The thermal behavior was correlated with the copolymer composition and functional groups, maleimide derivatives, on the copolymers. Thermal decomposition temperature (TDT) and glass transition temperature (Tg) were influenced by the functional groups of R‐PhMI moiety on the copolymer. The polymers showed an electrochemically irreversible reduction process under the conditions tested. CONCLUSION: Poly[(p‐chloromaleimide)‐co‐(2‐hydroxyethyl methacrylate)] copolymer shows a higher TDT than poly[(p‐hydroxymaleimide)‐co‐(2‐hydroxyethyl methacrylate)] or poly[(p‐nitromaleimide)‐co‐(2‐hydroxyethyl methacrylate)] (NPHE). Tg decreases in going from nitro to hydroxyl to chloro groups. The NPHE copolymer shows a lower stability, losing weight at 200 °C. The NPHE copolymer shows a well‐defined reduction wave which is similar to those of the other copolymers and it also shows an additional quasi‐reversible reduction wave corresponding to the nitrobenzene group. Copyright © 2009 Society of Chemical Industry  相似文献   

11.
Poly(p‐dioxanone)–poly(ethylene glycol)–poly(p‐dioxanone) ABA triblock copolymers (PEDO) were synthesized by ring‐opening polymerization from p‐dioxanone using poly(ethylene glycol) (PEG) with different molecular weights as macroinitiators in N2 atmosphere. The copolymer was characterized by 1H NMR spectroscope. The thermal behavior, crystallization, and thermal stability of these copolymers were investigated by differential scanning calorimetry and thermogravimetric measurements. The water absorption of these copolymers was also measured. The results indicated that the content and length of PEG chain have a greater effect on the properties of copolymers. This kind of biodegradable copolymer will find a potential application in biomedical materials. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:1092–1097, 2006  相似文献   

12.
The water‐insoluble resin poly(2‐acrylamido‐2‐methyl‐1‐propanosulfonic acid‐co‐4‐vinyl pyridine), through a radical polymerization solution, was synthesized with ammonium persulfate as an initiator and N,N‐methylene bisacrylamide as a crosslinking reagent. The metal‐ion‐retention properties were studied by batch and column equilibrium procedures for the following metal ions: Hg(II), Cu(II), Cd(II), Zn(II), Pb(II), and Cr(III). These properties were investigated under competitive and noncompetitive conditions. The effects of the pH, maximum retention capacity, and regeneration capacity were studied. The resin showed a high retention ability for Hg(II) ions at pH 2.0. The retention of Hg(II) ions from a mixture of ions was greater than 90%. The resin showed a high selectivity for Hg(II) with respect to other metal ions. The Hg(II)‐loaded resin was able to be recovered with 4M HClO4. The retention capacity was kept after four cycles of adsorption and desorption. The retention properties for Hg(II) were very similar with the batch and column methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3556–3562, 2003  相似文献   

13.
Two novel copolymers of polyfluorenes/poly(p‐phenylenevinylene)s copolymers with ptert‐butyl‐phenylenemethylene groups in the C‐9 position of alternating fluorene unit, poly[1,4‐(2,5‐dibutyloxyl)‐phenyleneviny lene‐alt‐9‐(ptert‐butyl‐phenylenemethylene)fluorene] and poly[1,4‐(2,5‐dioctyloxyl)‐phenylenevinylene‐alt‐9‐(ptert‐butyl‐phenylenemethylene)fluorine], have been synthesized via the Heck polycondensation reaction. The synthesized polymers were characterized by FTIR, NMR, DSC, TGA, UV–vis, and PL spectra. The polymers showed high glass transition temperatures and good thermal stability. A polymer light‐emitting diode with the configuration ITO/PEDOT:PSS/P2/Ca/Al has been fabricated. The device emitted a yellow light with a peak wavelength of 578 nm similar to the PL spectra of the copolymer film. A maximal luminance of 534 cd/m2 was obtained at a driving voltage of 24.5 V. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3955–3962, 2006  相似文献   

14.
NiCl2 (bpy)‐catalyzed polycondensation between p‐dibromobenzene and m‐dibromobenzene was carried out under various conditions. With the polycondensation, a series of copolymers with number‐average molecular weights of 2400 (by gel permeation chromatography with polystyrene standards) was formed, and some samples had good solubility in organic solvents. The IR spectra and the ultraviolet spectra measured in a tetrahydrofuran (THF) solution of the copolymer showed that there were p‐phenylene and m‐phenylene units in the copolymer. According to analyses with differential scanning calorimetry, thermogravimetric analysis, and X‐rays, with an increasing molar ratio of m‐phenyl units in the copolymer, the glass‐transition temperature, the temperature of viscous flow, and the crystallizability of the polyphenylene copolymer decreased. The fluorescence spectra of the copolymer measured in a THF solution showed an emission maximum at 373–376 nm, whereas the maximum shifted to 436.6 nm for the film. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2210–2215, 2003  相似文献   

15.
Two macroporous acrylonitrile/10% vinyl acetate/10% divinylbenzene copolymers as beads were obtained by the aqueous suspension copolymerization of the three comonomers in the presence of toluene as a diluent, which was used in two different amounts. These copolymers were chemically modified by their reactions with ethylenediamine, diethylenetriamine, and triethylenetetramine in the presence of water when the aminolysis–hydrolysis reaction of the nitrile groups and the hydrolysis reaction of the acetate groups occurred. From these reactions, weak‐base anion exchangers with high ion‐exchange capacities, between 1.6 and 2.2 mequiv/mL and 6.5 and 10.5 mequiv/g, were obtained. For these anion exchangers, the behaviors in the retention processes of the Ni(II), Cd(II), and Pb(II) cations were evaluated with the bath method. All the resins exhibited retention properties, but the retained amounts of the metal cations differed as a function of the resin and cation nature. Thus, the resin from the reaction with triethylenetetramine of the copolymer obtained in the presence of a larger amount of toluene could be considered the most suitable sorbent for the three metal cations, especially for Ni(II). Its maximum retention capacity for this cation was 2.67 mequiv/g of dried resin. From the noncompetitive and competitive retentions was observed the following selectivity order: Ni(II) > Cd(II) > Pb(II). The retention took place by the chelating processes between the functional groups with the ligand role, especially free amine groups, and metal cations. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 930–938, 2005  相似文献   

16.
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   

17.
Radical copolymerizations of 1‐vinyl‐2‐pyrrolidone with acrylamide and N,N′‐dimethylacrylamide at different feed ratios were investigated. The copolymers were characterized by Fourier transform infrared spectroscopy, 1H NMR, and 13C NMR spectroscopy. The copolymer composition was determined from the 1H NMR spectra and found to be statistical. The metal complexation of poly(acrylamide‐co‐1‐vinyl‐2‐pyrrolidone) and poly(N,N′‐dimethylacrylamide‐co‐1‐vinyl‐2‐pyrrolidone) for the metal ions Cu(II), Co(II), Ni(II), Cd(II), Zn(II), Pb(II), Fe(III), and Cr(III) were investigated in an aqueous phase. The liquid‐phase polymer‐based retention method is based on the retention of inorganic ions by soluble polymers in a membrane filtration cell and subsequent separation of low‐molecular compounds from the polymer complex formed. The metal ion interaction with the hydrophilic polymers was determined as a function of the pH and the filtration factor. Poly(N,N‐dimethylacrylamide‐co‐1‐vinyl‐2‐pyrrolidone) showed a higher affinity for the metal ions than poly(acrylamide‐co‐1‐vinyl‐2‐pyrrolidone). According to the interaction pattern obtained, Cr(III) and Cu(II) formed the most stable complexes at pH 7. Pb(II) and Zn(II) were not retained. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 741–750, 1999  相似文献   

18.
Poly(2‐aminobenzoic acid) and poly(3‐aminobenzoic acid) were synthesized by chemical polymerization of the respective monomers with aqueous 1M hydrochloric acid and 0.49M sodium hydroxide, using ammonium persulfate as an oxidizing agent. In addition, polymerization in an acid medium was carried out in the presence of metal ions, such as Cu(II), Ni(II), and Co(II). Poly(2‐aminobenzoic acid‐co‐aniline) and poly(3‐aminobenzoic acid‐co‐aniline) were synthesized by chemical copolymerization of aniline with 2‐ and 3‐aminobenzoic acids, respectively, in aqueous 1M hydrochloric acid. The copolymers were synthesized at several mole fractions of aniline in the feed and characterized by UV–visible and FTIR spectroscopy, the thermal stability, and the electrical conductivity. Metal ions, such as Cu(II), Ni(II), and Co(II), were incorporated into homo‐ and copolymers by the batch method. The percentage of metal ions in the polymers was higher in the copolymers than in the homopolymers. The thermal stability of the copolymers increased as the feed mole fraction of aniline decreased and varied with the incorporation of metal ions in the polymers. The electrical conductivity of the homo‐ and copolymers was measured, which ranged between 10?3 and 10?10 S cm?1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2641–2648, 2003  相似文献   

19.
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   

20.
The crosslinked poly(1‐vinylimidazole‐co‐acrylic acid), P(VIm‐co‐AA), and poly(1‐vinylimidazole‐co‐2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) P(VIm‐co‐APSA) were synthesized by radical polymerization and tested as adsorbents under competitive and noncompetitive conditions for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), and Cr(III) by batch equilibrium procedure. The resin–metal ion equilibrium was achieved before 1 h. The resin P(VIm‐co‐AA) showed a maximum retention capacity (MRC) value for Pb(II) at pH 3 and Hg(II) at pH 1 of 1.1 and 1.2 mEq/g, respectively, and the resin P(VIm‐co‐AA) showed at pH 3 the following MRC values: Hg(II) (1.5 mEq/g), Cd(II) (1.9 mEq/g), Zn(II) (2.7 mEq/g), and Cr(III) (2.8 mEq/g). The recovery of the resin was investigated at 25°C with 1 M and 4 M HNO3 and 1 M and 4 M HClO4. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2852–2856, 2003  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号