Polychelates of poly[N-(4-carboxy-3-hydroxyphenyl)maleimide]

The reactions of the bidentate polymeric chelating ligand poly[N-(4-carboxy-3-hydroxyphenyl)maleimide] with Co(II), Ni(II), Cu(II), Zn(II) and UO₂(II) metal ions were investigated. Analytical, magnetic, spectral and thermal studies were used to characterize these polychelates. All these polychelates are stable, intensely coloured solids and insoluble in common organic solvents.     

New polymeric Schiff base and its metal complexes

A novel polymeric Schiff base was synthesized by the reaction of a Schiff base from 2,4‐dihydroxy benzaldehyde and aniline with acryloyl chloride and was polymerized in methyl ethyl ketone at 70°C with benzoyl peroxide as a free‐radical initiator. Polychelates were obtained in an alkaline solution of poly(2‐hydroxy‐4‐acryloyloxy‐N‐phenylbenzylidine) with aqueous solutions of metal ions such as Cu(II), Ni(II), Co(II), Ca(II), Cd(II), Mn(II), and Zn(II). The polymeric Schiff base and polychelates were characterized with elemental analysis and spectral studies. The elemental analysis of the polychelates suggested that the metal‐to‐ligand ratio was 1:2. The IR spectral data of the polychelates indicated that the metals were coordinated through the nitrogen and oxygen of the phenolic ? OH group. Diffuse reflectance spectra, electron paramagnetic resonance, and magnetic moment studies revealed that the polychelates of the Cu(II) complex were square‐planar, those of the Ni(II), Mn(II), and Co(II) complexes were octahedral, and those of the Ca(II), Cd(II), and Zn(II) complexes were tetrahedral. X‐ray diffraction studies revealed that the polychelates were highly crystalline. The thermal properties of the Schiff base and polychelates were also examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 494–500, 2004     

Studies on various divalent metal complexes of poly(2-hydroxy-4-acryloyloxybenzophenone) in aqueous medium

2-Hydroxy-4-acryloyloxybenzophenone (2H4ABP) prepared by reacting acryloyl chloride with 2,4-dihydroxybenzophenone, was polymerized in 2-butanone at 65°C using benzoyl peroxide as initiator. Polychelates were obtained in the alkaline solution of poly(2H4ABP) with aqueous solutions of metal ions such as Ni(II), Mn(II), Co(II), Ca(II), Cd(II) and Zn(II). The polymer and polychelates were characterized by elemental analyses and spectral studies. Elemental analyses of the polychelates suggest that the metal-to-ligand ratio is 1: 2. The IR spectral data of the polychelates indicate that the metals were coordinated through the oxygen of the keto group and oxygen of the phenolic −OH group. The diffuse reflectance spectra, EPR and magnetic moments studies reveal that the polychelates of Cu(II) complex are square planar, and Ni(II), Mn(II) and Co(II) complexes are octahedral, while Ca(II), Cd(II) and Zn(II) complexes are tetrahedral. X-ray diffraction studies revealed that the polychelates are highly crystalline. The thermal and electrical properties of polymer and polymer–metal complexes are discussed. © 1998 SCI.     

Synthesis,characterization, and catalytic study of polymeric metal complexes derived from divalent transition metal ions with 2,4‐dihydroxy benzophenone and 2,4‐dihydroxy acetophenone

The polymeric metal complexes of poly (3‐hydroxy‐4‐((Z)‐1‐(phenylimino)ethyl)phenyl‐3‐methylbut‐2‐enoate) designated as [poly(3H4‐1PEPMB)] and poly (3‐hydroxy‐4‐((Z)‐phenyl(phenylimino)methyl)phenyl‐3‐methylbut‐2‐enoate designated as [poly(3H4‐PPMPMB)] containing Cu(II), Ni(II), Co(II), Cd(II), Mn(II), Ca(II), and Zn(II) ions were synthesized. The ploymer ligands and metal complexes were charcterized by Fourier transform infrared, nuclear magnetic resonance (NMR), thermogravimetric analysis, differential scanning calorimeter (DSC), and X‐ray diffraction (XRD) techniques. The XRD study of the complexes revealed highly crystalline nature of polychelates. The polymeric complexes were active for the oxidation of aldehyde group. The oxidation activity of Cu (II) complex of poly (3H4‐1PEPMB) was studied for the oxidation of benzaldehyde and its derivaties to corresponding carboxylic acids. The oxidation products were confirmed by GC‐MS analysis. The oxidation of aldehydes was quantitative with 100% selectivity for benzioc acid. Thermal analysis of complexes indicated reasonably good thermal stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Studies on poly(8‐hydroxy‐4‐azoquinolinephenylmethacrylate) and its metal complexes

8‐Hydroxy‐4‐azoquinolinephenylmethacrylate (8H4AQPMA) was prepared and polymerized in ethyl methyl ketone (EMK) at 65°C using benzoyl peroxide as free radical initiator. Poly(8‐hydroxy‐4‐azoquinolinephenylmethacrylate) poly(8H4AQPMA) was characterized by infrared and nuclear magnetic resonance techniques. The molecular weight of the polymer was determined by gel permeation chromatography. Cu(II) and Ni(II) complexes of poly(8H4AQPMA) were prepared. Elemental analysis of polychelates suggests that the metal‐ligand ratio is about 1 : 2. The polychelates were further characterized by infrared spectra, X‐ray diffraction, spectral studies, and magnetic moments. Thermal analyses of the polymer and polychelates were carried out in air. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1516–1522, 2006     

Polymer-metal complexes: Synthesis, characterization, and properties of poly(maleic acid) metal complexes with Cu(II), Co(II), Ni(II), and Zn(II)

SUMMARY Polymer metal complexes of poly(maleic acid) and Cu(II), Co(II), Ni(II), and Zn(II) were synthesized. Elemental analysis, as well as magnetic, spectral and thermal properties, in addition to electrical conductivities of the chelates were investigated, and possible structures have been assigned to the polychelates. Semi-empirical calculations at the PM3 level were carried out on the geometrical arrangement of the polychelates. Received: 19 November 1999/Revised version: 22 March 2000/Accepted: 31 March 2000     

Synthesis,characterization, and properties of polychelates of poly(styrene sulfonic acid‐co‐maleic acid) with Co(II), Cu(II), Ni(II), and Zn(II)

Polymer metal complexes of poly(styrene sulfonic acid‐co‐maleic acid) and Cu(II), Ni(II), Co(II), and Zn(II) were synthesized. The magnetic, spectral, and thermal properties, as well as the electrical conductivities, of the chelates were investigated, and possible structures were assigned to the polychelates. Semiempirical calculations at the AM1 level were carried out on the geometrical arrangement of the polychelates. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2546–2551, 2002     

Synthesis,characterization and antimicrobial activity of transition metal chelated thiourea‐formaldehyde resin

A polymeric ligand (thiourea‐formaldehyde resin ‐ TUFR) bearing nitrogen and sulfur donor groups was synthesized by the polycondensation of thiourea and formaldehyde in acidic medium and its polychelates were prepared in alcoholic solution of metal ions such as Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The TUFR polymeric ligand and its TUFR‐M(II) polychelates were characterized with micro‐analytical analysis and spectral studies. The FTIR spectra of polychelates indicated that the metal ions were coordinated through the sulfur of the thionyl (C?S) groups and formed a covalent bond with the nitrogen of the NH groups. Electronic spectra, electronic spin resonance (ESR) spectra and magnetic moments revealed that the polychelates of Mn(II), Co(II) and Ni(II) were octahedral; however, Cu(II) and Zn(II) polychelates were square‐planar and tetrahedral, respectively. The thermogravimetric analysis data indicated that the polychelates were more stable than the corresponding ligand. The antimicrobial activities of all the compounds against several bacteria and fungi were also investigated by using the agar well diffusion method. Copyright © 2006 Society of Chemical Industry     

Systematic study of ion-exchange properties and ligating behaviour of respropiophenone-formaldehyde copolymers

Respropiophenone-formaldehyde copolymers (RPP-F) were synthezised by the condensation of 2,4-dihydroxypropiophenone (respropiophenone (RPP)) and formaldehyde (F) in the presence of NaOH or H₂SO₄ as catalyst with varied molar ratios of reacting monomers. The copolymers were characterized by elemental analysis, IR spectra, viscosity, and TGA studies. Their M?_n was determined by nonaqueous conductometric titrations and vapour pressure osmometry (VPO). Chelation ion-exchange properties have also been studied employing the batch equilibration method. Polychelates of Cu(II), Ni(II), Co(II), Mn(II), Zn(II), VO(II), and UO₂(II) with RPP-F-AI copolymer were prepared. The analytical data agree with 1 : 2 metal-ligand stoichiometry. Elemental analysis, magnetic, spectral, and thermal properties of polychelates have been studied and probable structures are assigned to the polychelates. All the polychelates are amorphous powders, insoluble in common organic solvents.     

Synthesis,structure and magnetic properties of a trinuclear cyano-bridged complex [Cu(bappz)(μ-NC)Ni(CN)2(μ-CN)Cu(bappz)](ClO4)2 {bappz=1,4-bis(3-aminopropyl)piperazine}

The bimetallic trinuclear complex [Cu(bappz)(μ-NC)Ni(CN)₂(μ-CN)Cu(bappz)](ClO₄)₂ (bappz=1,4-bis(3-aminopropyl)piperazine) has been prepared from the reaction of [Cu(bappz)](ClO₄)₂ and K₂[Ni(CN)₄] in water and its crystal and molecular structure has been determined. The structure consists of a trinuclear [Cu(bappz)(μ-NC)Ni(CN)₂(μ-CN)Cu(bappz)]²⁺ cation and two perchlorate anions. The bridging [Ni(CN)₄]²⁻ anion is coordinated by two [Cu(bappz)]²⁺ cations through two cyano groups, providing a novel trinuclear structure with the Cu–(NC)–Ni–(CN)–Cu linkage. The nickel(II) ion is four-coordinated by carbon atoms from four cyano groups (two of them, in trans position, form a bridge) in a square planar arrangement, whereas both the copper(II) ions are five-coordinated by four bappz nitrogens and one cyanide nitrogen in a distorted square–pyramidal geometry. The temperature dependence of magnetic susceptibility was measured for this compound over the range of 2–300 K. The magnetic investigation showed the presence of a very weak antiferromagnetic interaction (superexchange interaction parameter J=−0.54 cm⁻¹) between the copper atoms through the diamagnetic [Ni(CN)₄]²⁻ ion.     

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     

Synthesis,spectral, thermal,and chelation potentials of polymeric hydrazone based on 2,4‐dihydroxy benzophenone

A chelating polymer, poly(2,4‐dihydroxy benzophenone hydrazone–formaldehyde) [poly(DHBPH–F)], was synthesized by the polycondensation of 2,4‐dihydroxy benzophenone hydrazone with formaldehyde in the presence of oxalic acid as a catalyst. Poly(DHBPH–F) was characterized by Fourier transform infrared and ¹H‐NMR spectral data. The molecular weight of the polymer was determined by gel permeation chromatography. Polychelates were obtained when the dimethylformamide solution of the polymer containing a few drops of ammonia was treated with an aqueous solution of metal ions. Elemental analysis of the polychelates indicated that the metal–ligand ratio was 1 : 2. The IR spectra of the polymer–metal complexes suggested that the metals were coordinated through the oxygen of the phenolic? OH group and the nitrogen of the azomethine group. The electron paramagnetic resonance and magnetic moment data indicated a square planar configuration for Cu(II) chelate and an octahedral structure for Ni(II) chelate. The thermogravimetric analysis, differential scanning calorimetry, and X‐ray diffraction data indicated that the incorporation of the metal ions significantly enhanced the degree of crystallinity. The polymerization initiation, electrical conductivity, and catalytic activity of the polychelates are discussed. Heavy‐metal ions [viz., Cu(II) and Ni(II)] were removed with this formaldehyde resin, and the metal‐ion uptake efficiency at different pH's, the nature and concentration of the electrolyte, and the reusability of the resin were also studied. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Antimicrobial Polychelates: Synthesis and Characterization of Transition Metal Chelated Barbituric Acid–Formaldehyde Resin

A monomeric Schiff base was prepared by the condensation reaction of salicylaldehyde and semicarbazide, which further react with formaldehyde and barbituric acid-formed polymeric Schiff base. Its metal polychelates were then formed with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II). All the synthesized compounds were characterized by elemental analysis, magnetic moment, FTIR, ¹HNMR, and electronic spectroscopies. The elemental analysis data show the formation of 1:1 [M: L] metal polychelates. Thermogravimetric analysis was carried out to find the thermal behavior of all the synthesized polymeric compounds and thermal data revealed that all the metal polychelates are more thermally stable than their parent polymeric Schiff base. All the synthesized polymeric compounds were screened for antimicrobial activity against some clinically important microorganisms, such as Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Staphylococcus typhi, Candida albicans, Microsporum canis, and Aspergillus niger. In vitro antimicrobial activity was determined by the Agar Well Diffusion method and the result shows that all the metal polychelates exhibited better antimicrobial activity than their parent polymeric Schiff base.     

Synthesis,characterization of poly(allylamine)chelates with Cu(II), Co(II) and Ni(II)

Summary The parent polymer, poly(allylamine) as ligand polymer was employed to synthesize polychelates of heavy metal ions. The functional poly(allylamine) and its Ni(II), Co(II) and Cu(II) metal chelates were characterized by elemental analysis, FT-IR spectroscopy, TGA, and SEM. For the polychelates magnetic and conductivimetry studies were also carried out.     

Synthesis and spectroscopic characterization of N-substituted thiosemicarbazone complexes

Complexation between Co(II), Ni(II), and Cu(II) with some 3,4-hexanedione bis[N-substituted thiosemicarbazones] has been investigated. The ligands release the two hydrazine hydrogens during the complex formation and act as binegative tetradentate (N₂S₂) except [Cu(H₂Hx4M)Cl₂] and [Cu(H₂Hx4Et)Cl₂]2H₂O in which the ligands behave as neutral tetradentate. The magnetic moments and electronic spectra provide information about the geometry of the complexes, which is supported by calculating the ligand field parameters for the Co(II) complexes. Most Ni(II) complexes are diamagnetic, indicative of a square-planar structure. The bands observed in Nujol are shifted to higher energies in dimethylformamide (DMF) solution, suggesting a weak interaction with the solvent. The ESR spectra of the complexes in solid and DMF solution exhibit axial symmetric g-tensor parameters with g _|>g _⊥>2.0023. The molecular parameters of [Ni(Hx4M)] have been calculated theoretically by semiempirical PM3 method. Also, the electronic transitions were calculated theoretically and found approximately similar to those recorded experimentally.     

Studies on poly(2-hydroxy-4-acryloyloxybenzophenone)-metal complexes

2-Hydroxy-4-acryloyloxybenzophenone (HABP), prepared from acryloyl chloride with 2,4-dihydroxybenzophenone, was polymerized in methyl ethyl ketone at 70°C using benzoyl peroxide as initiator. Polychelates were obtained in the dimethylformamide solution of poly(HABP) containing a few drops of ammonia with the aqueous solution of Cu(II)/Ni(II) ions. The polymer and polychelates were characterized by elemental analyses and spectral studies. Elemental analyses of the polychelates suggest a metal to ligand ratio of 1:2. The IR spectral data of polychelates indicate that the metals were coordinated through the oxygen of the keto group and the oxygen of the phenolic-OH group. The diffuse reflectance spectra, electron paramagnetic resonance, and magnetic moments of the polychelates show an octahedral and square planar structure for poly(HABP)-Ni(II) and poly(HABP)-Cu(II) complexes, respectively. X-ray diffraction studies revealed a high crystalline nature of the polychelates. The thermal properties of polymer and metal complexes and their catalytic activity are discussed. © 1996 John Wiley & Sons, Inc.     

Poly(styrene‐alt‐maleic acid)–metal complexes with divalent metal ions. synthesis,characterization, and physical properties

Polymer–metal complexes of the alternating copolymer styrene and maleic acid with Cu(II), Co(II), Ni(II), and Zn(II) were synthesized and characterized by elemental analysis, infrarred and electronic spectra, and thermogravimetry. In addition, magnetic measurements were performed and the electrical conductivity was studied at different temperatures. Semiempirical calculations at the PM 3 level were carried out to elucidate the geometrical arrangement of the polychelates. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1310–1315, 2001     

Removal of chromium,copper, and nickel ions using bidentate polymeric ligand derived from 4‐aminophenol and salicylaldehyde

The monomer 5‐(4‐acryloyloxyphenylazo)salicylaldehyde [5,4‐APASAL] was prepared and polymerized in dimethylformamide (DMF) at 70°C using benzoyl peroxide as free radical initiator. Poly5‐(4‐acryloyloxyphenylazo) salicylaldehyde [poly(5,4‐APASAL)] was characterized by infrared and nuclear magnetic resonance spectroscopic technique. The molecular weight of the polymer was determined by gel permeation chromatography method. Cu(II), Ni(II), Cr(III), and Cr(VI) complexes of poly(5,4‐APASAL) were prepared. Elemental analysis of polychelates suggests that the metal to ligand ratio is about 1 : 2. The polymer metal complexes were also characterized by XRD, magnetic moment, and thermal analysis. The effect of pH and electrolyte concentration in the metal uptake behavior of the polymer was also studied. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthetic,spectroscopic, magnetic,thermal, and antimicrobial approach towards new biocidal coordination polymers

O‐aminophenol was reacted with glutraldehyde to obtain Schiff base, which was then reacted with formaldehyde in slight acidic medium to generate phenolic groups. Now the substituted Schiff base was reacted with the transition metal acetates of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) to get polymeric metal complexes. Their structures have been elucidated on the basis of elemental analyses, ¹H NMR spectra, ¹³C NMR spectra, magnetic measurements, thermogravimetric analyses, electronic spectra, and infrared spectra. The results are in accordance with an octahedral environment around the central metal ion. The polychelates of Mn(II), Co(II), Ni(II), and Cu(II) are paramagnetic while Zn(II) polychelate was found to be diamagnetic. The synthesized Schiff base acted as a uninegative bidentate ligand and bonding occurs through the hydroxyl oxygen and nitrogen atoms. The thermal behavior of these coordinating polymers was studied by TGA in nitrogen atmosphere up to the temperature range of 800°C. All the synthesized polychelates were also screened for their biocidal activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis (bacteria), Candida albicans, and Muller species (yeast) by using agar well diffusion method. All the metal polychelates show promising antimicrobial activities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124:3971–3979, 2012     

Polychelates of poly(acrylic acid-co-acrylamide)with Cu(II), Co(II), and Ni(II) Synthesis and properties

SUMMARY Polychelates were obtained by addition of an aqueous solution of the poly(acrylic acid-co-acrylamide) to an aqueous solution of Cu(II), Co(II), and Ni(II). All the polychelates were insoluble in water and in common organic solvents. The polychelates were characterized by elemental analysis, FT-IR spectroscopy thermogravimetry, and showed tetrahedral arrangement for Co(II) and Ni(II). Magnetic and conductivity studies for all the polychelates were also carried out. The poly(acrylic acid-co-acrylamide) behaved as semiconductor. Received: 25 July 1997/Revised version: 1 December 1997/Accepted: 5 December 1997