Resacetophenone‐formaldehyde resins, II. Chelation ion‐exchange properties

Copolymers (p-CMF) synthesized by the condensation of p-cresol and melamine with formaldehyde in the presence of an acid catalyst and using varied molar proportion of the reacting monomers. Copolymer resin compositions were determined on the basis of their elemental analysis. The number average molecular weight of these copolymers was determined by conductometric titration in nonaqueous media. Solution viscosity measurements in dimethyl sulfoxide (DMSO) were carried out to ascertain the characteristic functions and constants of the copolymer resins. The copolymer resins were further characterized by UV-visible absorption spectra in the nonaqueous medium, Infra-red (IR) spectra, and the nuclear magnetic resonance (NMR) spectra. Thermal studies of the resins were carried out to determine their mode of decomposition, the activation energy (E a ), order of reaction (n), frequency factor (Z), entropy change (DS), free energy change (DF), and apparent entropy change (S*). Thermal decomposition curves were discussed with careful attention of minute details. The Freeman-Carroll and Sharp-Wentworth methods have been used to calculate thermal activation energy and thermal stability. Thermal activation energy (E a ) calculated with these methods are in agreement with each other. The data from the Freeman-Carroll methods have been used to determine various thermodynamic parameters. The order of thermal stability of copolymers has been determined using TGA.

Section: Introductionmentioning

confidence: 99%

Synthesis, characterization, and thermal degradation studies of copolymer resin derived from p‐cresol, melamine, and formaldehyde

Singru

Zade

Gurnule³

2008

“…2 Selective chelation of specific metal ions from a metal ion mixture by using a number of tetradentate ligands attached to polystyrene divinylbenzene was demonstrated by Melby et al 3 Chelating resins prepared by copolycondensation of 8-hydroxyquinoline or phenol derivatives like 2-amino phenol, ␤-resorcylic acid, or resorcinol with formaldehyde were reported by Pennington and Williams 4 and Aristov et al 5 Sykora et al 6 prepared a selective ionexchange resin by reacting a condensation product of 2,4-dihydroxyacetophenone and anthranilic acid with formaldehyde. Parmer et al 7 synthesized 2,4-dihydroxy acetophenone formaldehyde resin in an acidic medium and studied its chelation properties. Preparation of a copper-selective polymeric ligand by the reaction of phenol formaldehyde and piperazine was reported by Hodgkin et al 8 In continuation of our research 9,10 in this area, the present article deals with the synthesis and characterization of poly(8-hydroxy-4-azoquinolinephenol-formaldehyde) and its Cu(II) and Ni(II) metal complexes.…”

Section: Introductionmentioning

confidence: 99%

Studies of poly(8‐hydroxy‐4‐azoquinolinephenol‐formaldehyde) and its metal complexes

Vijayalakshmi

Subramanian

Rajagopan

et al. 2006

Poly(8-hydroxy-4-azoquinolinephenol-formaldehyde) resin (8H4AQPF) was prepared by condensing 8-hydroxy 4-azoquinoline phenol with formaldehyde (1 : 1 mol ratio) in the presence of oxalic acid. Polychelates were obtained when the DMF solution of poly(8H4AQPF) containing a few drops of ammonia was treated with the aqueous solution of Cu(II) and Ni(II) ions. The polymeric resin and polymer-metal complexes were characterized with elemental analysis and spectral studies. The elemental analysis of the polymer-metal complexes suggested that the metalto-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 OOH group. Diffuse reflectance spectra, electron paramagnetic resonance, and magnetic moment studies revealed that the polymermetal complexes of the Cu(II) complexes were square planar and those of the Ni(II) complexes were octahedral. X-ray diffraction studies revealed that the polymer metal complexes were crystalline. The thermal properties of the polymer and polymer-metal complexes were also examined.

“…The synthesis and characterization of 2, 4‐ dihyroxyacetophenone with 1, 4‐butanediolcopolymer and its ion exchange properties have been reported 16. Chelation ion exchange resins derived from 2‐hydroxy‐4‐methoxyacetophenone and thiourea with trioxane was investigated by Pancholi et al17 Patel and coworkers18, 19 reported the ion exchange properties of resacetophenone (2, 4 dihydroxy Acetophenone) ‐formaldehyde and resacetophenone oxime‐formaldehyde resins. In our laboratory, extensive research work was carried out on synthesis and characterization of terpolymers and their ion exchange properties 20–22.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of resin IV: Salicylic acid, diaminonaphthalein, and formaldehyde terpolymer and its ion exchange

Masram

Bhave

Kariya³

2010

This article reports the synthesis, characterization, and ion exchange properties of a terpolymer. The terpolymer resin salicylic acid-diaminonaphthaleinformaldehyde (SDNF) was synthesized by the condensation of salicylic acid and diaminonaphthalein with formaldehyde in the presence of a hydrochloric acid catalyst. Terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance spectroscopy, and UV-Visible spectral studies. The number average molecular weight of the resin was determined by nonaqueous conductometric titration.