Poly(acrylic acid‐co‐vinylsulfonic acid): Synthesis,characterization, and properties as polychelatogen

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     

The adsorption of Cu(II) ion from aqueous solution upon acrylic acid grafted poly(ethylene terephthalate) fibers

This study is concerned with the investigation of the adsorption properties of acrylic acid grafted poly(ethylene terephthalate) fibers by the use of Cu(II) ions in aqueous solutions. Influence of pH, graft yield, contact time, concentration of the ion, and reaction temperature on the amount of ion adsorbed upon reactive fiber were investigated. The time in which the adsorption reached to the equilibrium value was determined as 1 h. The adsorption isotherm of Cu(II) ion was found to be a Langmuir type and the heat of adsorption was calculated as ?10.1 kJ mol^?1. It was observed that the adsorbed Cu(II) ion upon acrylic acid grafted poly(ethylene terephthalate) fibers could be recovered in acidic media. The fiber could also readsorb Cu(II) ions without losing its activity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1216–1220, 2003     

Interactions of polyelectrolytes bearing carboxylate and/or sulfonate groups with Cu(II) and Ni(II)

The interactions between the water-soluble polyelectrolytes poly(acrylic acid) (PAA) and poly(vinyl sulfonic acid) (PVS), and Cu(II) and Ni(II) are studied by the liquid-phase polymer-based retention (LPR) technique. Assuming a Ni(II)-PVS interaction of electrostatic nature, the nature of the Ni(II)-PAA interaction is found to be electrostatic, while Cu(II)-PAA interactions imply the formation of coordinative bonds. The charge related formation constants for the systems Ni(II)-PAA, Ni(II)-PVS, and Cu(II)-PVS are found to be 57.57×10², 43.4×10², and 60.5×102 M⁻¹, respectively in a 0.010 M NaNO₃ aqueous solution at pH 5, and 1.4×10² for both systems containing Ni(II) and 1.3×10² M⁻¹ for the system Cu(II)-PVS in a 0.10 M NaNO₃ aqueous solution at pH 5.     

Polyelectrolyte‐assisted removal of metal ions with ultrafiltration

The water‐soluble polymers poly(styrene sulfonic acid‐co‐maleic acid) and poly(acrylic acid‐co‐maleic acid) were investigated with respect to their metal‐ion‐binding ability with ultrafiltration. The studied metal ions included Ag(I), Cu(II), Ni(II), Co(II), Ca(II), Mg(II), Pb(II), Cd(II), Zn(II), Al(III), and Cr(III) ions. The retention properties of the polyelectrolytes for the metal ions depended strongly on the ligand type. As for the carboxylate ligands, with increasing concentration and pH, the metal‐binding affinity increased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1091–1099, 2005     

Interaction of poly(maleic anhydride‐alt‐acrylic acid) with transition metal cations,Ni2+, Cu2+, and Cd2+: A study by UV–Vis spectroscopy and viscosimetry

Interactions between poly(maleic anhydride‐alt‐acrylic acid), [poly(MA‐alt‐AA)] and Cu²⁺, Ni²⁺, and Cd²⁺ ions were studied by UV–vis spectroscopy and viscosimetry. Effects of nature and the concentrations of the metal ions on the complex formation were investigated and the formation constants of each complex were determined by the mole‐ratio method. UV–vis studies showed that the complex formation tendency increased in the followed order: Cd(II) < Ni(II) < Cu(II). This order was confirmed by the Irving–William series and the Pearson's classification. The influence of metal ions on the reduced viscosity of poly(MA‐alt‐AA) increased in the following order: Cu(II) < Ni(II) < Cd(II), and this result was explained by the concentration effect. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2698–2705, 2004     

Low molecular weight polyacrylic acid with pendant aminomethylene phosphonic acid groups

Low molecular weight poly(acrylic acid‐co‐vinyl aminomethylene phosphonic acid)s were prepared by consecutively applying the Hofmann degradation and the Mannich reaction to polyacrylamide and poly(acrylamide‐co‐acrylic acid)s. ¹H‐NMR, ³¹P‐NMR, and microanalysis were used for structural analyses. These polymers were tested as anti‐scalent and they showed better anti‐scalent effect than commercial poly(acrylic acid)s. The scale inhibition properties of copolymers increased with increasing amount of aminomethylene phosphonic acid groups. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 870–874, 2000     

Metal ion retention properties of water‐insoluble polymers containing carboxylic acid groups

Crosslinked poly(acrylic acid), PAA, and poly(2‐acrylamidoglycolic acid), PAAG, were synthesized by radical polymerization. Both resins contain carboxylic acid groups. PAA at basic pH exists basically as an acrylate anion and PAAG shows three atoms or groups, carboxylic acid, hydroxyl, and amide groups, that can act as ion exchanger or chelating groups. Both resins are studied as adsorbents to trace metal ions from saline aqueous solutions and natural sea water and their properties by Batch equilibrium procedure are compared. The metal ions studied under competitive and noncompetitive conditions were Cu(II), Pb(II), Cd(II), and Ni(II). The effects of pH, time of contact, amount of resin, temperature, and salinity were studied. Resin PAA shows a high affinity (>80%) for Cu(II) and Cd(II) and resin PAAG shows also a high affinity for Ni(II), Pb(II), and Cd(II). By treatment of the metal ion‐loaded resin with 4M HNO₃ it is possible to recover completely the Cu(II) ions from resin PAA and Ni(II) and Pb(II) from resin PAAG. The metal ion retention properties were studied with natural sea water. For those natural sea waters containing Cu(II) and Cd(II), the resins showed a high affinity for Cd(II) ions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 697–705, 2006     

Trace metal ion retention properties of crosslinked poly(4‐vinylpyridine) and poly(acrylic acid)

The crosslinked resins poly(4‐vinylpiridine) (PVPy) and poly(acrylic acid) (PAA) were obtained by radical polymerization. PVPy shows monodentate ligands and PAA at basic pH is basically as acrylate anion, which can contain end‐carboxylates groups or form a bridge acting as mono‐ or bidentate ligands. The retention properties for trace metal ions from saline aqueous solutions and natural seawaters of these two resins were investigated by Batch equilibrium procedure. The metal ions studied were Cu(II), Pb(II), Cd(II), and Ni(II). The following effects were studied: pH, contact time, amount of the adsorbent, temperature, and salinity. The resin PVPy showed a high affinity for Cd(II) and PAA for Cu(II) and Cd(II). The metal ions were determined in the filtrate by atomic absorption spectrometry. By the treatment of the loaded resin with 4M HNO₃, it was possible to remove completely the Cu(II) ions. The retention properties of the resins were studied for trace metal ions present in the natural seawaters. Both resins showed a high affinity for Cd(II) when the natural seawater contained Cu(II) and Cd(II). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2908–2916, 2004     

Poly(2-acrylamido glycolic acid): A water-soluble polymer with ability to interact with metal ions in homogenous phase

A water-soluble polymer, poly(2-acrylamido glycolic acid) was obtained by radical polymerization and characterized by FT-IR, ¹H NMR, and ¹³C NMR spectroscopy. The metal ion retention properties were investigated through the liquid-phase polymer based retention (LPR) technique at different pHs and filtration factor Z. The affinity of the ligand groups for the metal ions depends strongly on the pH. At lower pH, the retention is lower than 50%, which increased as the pH increased. At pH 5, the polymer showed a high affinity and selectivity for Pb(II), and at pH 7 the P(AGA) formed stable complexes with Cu(II), Co(II), Ni(II), Cd(II), and Pb(II). Of the three potential ligand groups, amide, hydroxyl, and carboxylate groups, the carboxylate groups form the more stable complexes with the metal ions.     

Metal ion retention properties of poly(acrylic acid) and poly[N‐3‐(dimethylamino)propyl acrylamide‐co‐acrylic acid]

The crosslinked resins poly(acrylic acid) (PAA) and poly[N‐3‐(dimethylamino)propyl acrylamide‐co‐acrylic acid] [P(NDAPA‐co‐AA)] are obtained by radical polymerization and characterized by FTIR spectroscopy. PAA at basic pH exists basically as an acrylate anion that may contain end carboxylate groups or form bridges acting as mono‐ or bidentate ligands. P(NDAPA‐co‐AA) presents three potential ligand groups in its structure: carboxylic acid, amide, and amine. The trace metal ion retention properties of these two resins is compared by using the batch equilibrium procedure. The metal ions are contained in saline aqueous solutions and are found in natural seawater. The retention of Cu(II), Pb(II), Cd(II), and Ni(II) metal ions is studied under competitive and noncompetitive conditions. The effects on the pH, contact time, amount of adsorbent, temperature, and salinity are investigated. The PAA resin presents a high affinity (>80%) for Cu(II) and Cd(II) ions. The P(NDAPA‐co‐AA) resin shows a high affinity for Pb(II) and Cd(II) ions. With 4M HNO₃ it is possible to completely recover the PAA resin charged with Cu(II) ions and the P(NDAPA‐co‐AA) resin charged with Pb(II) ions. The two resins show a high affinity for Cd(II) ions from the seawater containing Cu(II) and Cd(II) ions. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1385–1394, 2005     

Synthesis,characterization, and metal complexation of poly(N‐phenylmaleimide‐co‐acrylic acid) and poly(N‐phenylmaleimide‐co‐acrylamide) as polychelatogens in aqueous solution

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     

Thermal properties of poly(maleic anhydride‐alt‐acrylic acid) in the presence of certain metal chlorides

Polychelates were synthesized by the addition of aqueous solutions of copper(II), cadmium(II), and nickel(II) chlorides to aqueous solutions of poly(maleic anhydride‐alt‐acrylic acid) [poly(MA‐alt‐AA)] in different pH media. The thermal properties of poly(MA‐alt‐AA) and its metal complexes were investigated with thermogravimetry and differential scanning calorimetry (DSC) measurements. The polychelates showed higher thermal stability than poly(MA‐alt‐AA). The thermogravimetry of the polymer–metal complexes revealed variations of the thermal stability by complexation with metal ions. The relative thermal stabilities of the systems under investigation were as follows: poly(MA‐alt‐AA)–Cd(II) > poly(MA‐alt‐AA)–Cu(II) > poly(MA‐alt‐AA)–Ni(II) > poly(MA‐alt‐AA). The effects of pH on the complexation and gravimetric analysis of the polychelates were also studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3926–3930, 2006     

Improving water solubility of poly(acrylic acid‐co‐styrene) copolymers by adding styrene sulfonic acid as a termonomer

Acrylic acid is often used to make water‐soluble polymers while styrene is often modified to add special functions to polymers. However, when styrene and acrylic acid are copolymerized, the resulting polymer is much less water soluble. To regain water solubility, the effect of styrene sulfonic acid on solubility of poly(acrylic acid‐co‐styrene) copolymers was investigated. Even though acrylic acid polymers are known for their water solubility, the presence of styrene units within acrylic acid copolymers reduces the solubility of the copolymer substantially at the natural pH of the solutions. By adding styrene sulfonic acid as a termonomer, polymers that are water soluble at the natural pH of the polymerization could be obtained. The solubility of the polymer after removal of the solvent and by redissolving at different concentrations and pH levels is also reported. Solubility increases at higher pH especially with low styrene concentration in the copolymer. It was found that incorporation of as little as 5 mol % of styrene into poly(acrylic acid) reduced the aqueous solubility to less than 0.5 g dL^?1 at pH 7. Upon adding 7 mol % styrene sulfonic acid as a termonomer, the water solubility increased to 5 g dL^?1 at pH 7. At higher levels of styrene, more styrene sulfonic acid was needed, especially at low pH. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis of water‐insoluble functional copolymers containing amide,amine, and carboxylic acid groups and their metal‐ion‐uptake properties

The crosslinked poly[N‐(3‐dimethylamino)propylmethacrylamide] [P(NDAPA)] and poly[N‐(3‐dimethylamino)propylmethacrylamide‐co‐acrylic acid] [P(NDAPA‐co‐AA)] were synthesized by radical polymerization. The resins were completely insoluble in water. The metal‐ion‐uptake properties were studied by a batch equilibrium procedure for the following metal ions: silver(I), copper(II), cadmium(II), zinc(II), lead(II), mercury(II), chromium(III), and aluminum(III). The P(NDAPA‐co‐AA) resin showed a lower metal‐ion affinity than P(NDAPA), except for Hg(II), which was retained at 71% at pH 2. At pH 5, the resin showed a higher affinity for Pb(II) (80%) and Cu(II) (60%), but its affinity was very low for Zn(II) and Cr(III). The polymer ligand–metal‐ion equilibrium was achieved during the first 20 min. By changing the pH, we found it possible to remove between 60 and 70% of Cd(II) and Zn(II) ions with (1M, 4M) HClO₄ and (1M, 4M) HNO₃. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:5232–5239, 2006     

Synthesis,characterization and polychelatogenic properties of poly[(2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid)‐co‐(methacrylic acid)]

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     

Synthesis,characterization, and catalytic activity of 4 mol % N,N′‐methylene bisacrylamide crosslinked poly(acrylic acid)–metal complexes

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     

Resins with the ability to bind copper and uranyl ions

Crosslinked poly(1‐vinyl imidazole‐co‐acrylic acid) and crosslinked poly(1‐vinylmidazole‐co‐2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) were synthesized by radical polymerization and characterized by elemental analysis and FTIR spectroscopy. The polymerization yields were 79 and 99%, respectively. The metal ion binding properties for copper(II) and uranium(VI) were studied under noncompetitive and competitive conditions by Batch equilibrium procedure. The resin crosslinked poly(1‐vinyl imidazole‐co‐acrylic acid) showed a higher dependence on pH than crosslinked poly(1‐vinylmidazole‐co‐2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid). The retention of uranyl ions for the latter resin was close to 100% at pH 5.0. The higher maximum retention capacity was close to 0.8 mmol/g dry resin at pH 5.0. Regeneration of the resin was possible by treatment with basic eluent. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 706–711, 2006     

Voltammetric investigation of polyelectrolyte-Cu(II) complexes

The complexation behaviours of poly(N-vinylcarbazole) (PNVCz), poly(acrylic acid) (PAA) poly(itaconic acid) (PIA) and their copolymers, synthesized by using different initial monomer compositions, with Cu(II) ions were investigated by the voltammetric technique. Their solutions were prepared in THF-water mixture according to the water-insoluble nature of PNVCz and its copolymers. The polymeric ligand-Cu(II) interactions, i.e. complex formations were studied as a function of copper ion concentration and copolymer composition. It was observed that although the cyclic voltammogram (CV) of Cu(II) alone in THF-water mixture was characterized by one redox wave, which has an irreversible nature, it became more reversible in the presence of polymer. Further, the CV results indicated the presence of two different electron transfer mechanisms, depending on the n _COOH/n _Cu(II) ratio and the carboxyl content of the copolymers.     

Poly(N,N′-dimethylacrylamide-co-acrylic acid): Synthesis,characterization, and application for the removal and separation of inorganic ions in aqueous solution

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     

Determination of the competitive adsorption of heavy metal ions on poly(n‐vinyl‐2‐pyrrolidone/acrylic acid) hydrogels by differential pulse polarography

Poly(N‐vinyl‐2‐pyrrolidone) and poly(N‐vinyl‐2‐pyrrolidone/acrylic acid) hydrogels were prepared by gamma irradiation for the removal of heavy metal ions (i.e., lead, copper, zinc, and cadmium) from aqueous solutions containing different amounts of these ions (2.5–10 mg/L) and at different pH values (1–13). The observed affinity order in adsorption of these metal ions on the hydrogels was Zn(II) > Pb(II) > Cu(II) > Cd(II) under competitive conditions. The optimal pH range for the heavy metal ions was from 7 to 9. The adsorption of the heavy metal ions decreased with increasing temperature in both water and synthetic seawater conditions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2013–2018, 2003