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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.
Copolymers (8‐HQ5‐SAOF) were synthesized by the condensation of 8‐hydroxyquinoline 5‐sulphonic acid (8‐HQ5‐SA) and oxamide (O) with formaldehyde (F) in the presence of acid catalyst. Four different copolymers were synthesized by using varied molar proportion of the reacting monomers. Copolymer resin composition has been determined on the basis of their elemental analysis and average molecular weights of these resins were determined by conductometric titration in nonaqueous medium. Viscometric measurement in dimethyl sulphoxide (DMSO) has been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, FTIR, and proton nuclear magnetic resonance spectra were studied to elucidate the structures. The newly synthesized copolymer proved to be a selective chelating ion‐exchange copolymer for certain metals. The chelating ion‐exchange properties of this synthesized copolymer was studied for different metal ions such as Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, and Pb2+. A batch equilibrium method was used in the study of the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion only for representative copolymer 8‐HQ5‐SAOF‐I due to economy of space. The study was carried out over a wide pH range, shaking time, and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+, Cu2+, and Ni2+ ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

3.
Terpolymers have been prepared by the condensation of 2,4‐dihydroxyacetophenone (2,4‐HA) and dithiooxamide (D) with formaldehyde (F) in the presence of hydrochloric acid as catalyst with varying the molar proportions of the reactant. Compositions of the terpolymer have been determined by elemental analysis. The number average molecular weight has been determined by conductometric titration in nonaqueous medium. Intrinsic viscosities of the solution of the terpolymer have been determined in N,N‐dimethyl formamide (DMF). The terpolymers have been characterized by UV–visible, IR, and proton NMR spectra. Chelation ion‐exchange properties have also been studied employing the batch equilibrium method. It was employed to study selectivity of metal ion uptake over a wide pH range and in media of various ionic strength. The overall rate of metal uptake follows the order: Fe3+ > Cu2+ > Ni2+ > Co2+ = Zn2+. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

4.
Terpolymer resins (8‐HQDF) were synthesized by the condensation of 8‐hydroxyquinoline (8‐HQ) and dithiooxamide (D) with formaldehyde (F) in the presence of acid catalyst and using varied molar ratios of reacting monomers. Terpolymer resins compositions have been determined on the basis of their elemental analysis and the number average molecular weights of these resins were determined by conductometric titration in non‐aqueous medium. Viscometric measurements in dimethyl formamide (DMF) have been carried out with a view to ascertain the characteristic functions and constants. The UV‐visible, FTIR, and proton nuclear magnetic resonance (H+ NMR) spectra were studied to elucidate the structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

5.
Terpolymers 8‐hydroxyquinoline 5‐sulphonic acid–melamine–formaldehyde (8‐HQ5‐SAMF) were synthesized through the condensation of 8‐hydroxyquinoline 5‐sulfonic acid and melamine with formaldehyde in the presence of an acid catalyst. Four different terpolymers were synthesized with various molar proportions of the reacting monomers. The terpolymer resin compositions were determined on the basis of elemental analysis. The number‐average molecular weights of these resins were determined by conductometric titration in a nonaqueous medium; viscometric measurements in dimethyl sulfoxide were carried out to ascertain the characteristic functions and constants. Ultraviolet–visible, Fourier transform infrared, 1H‐NMR, and 13C‐NMR spectroscopy and thermogravimetric analysis were used to elucidate the structures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

6.
A copolymer (4‐HAOF) prepared by condensation of 4‐hydroxyacetophenone and oxamide with formaldehyde in the presence of an acid catalyst proved to be a selective chelating ion‐exchange copolymer for certain metals. Chelating ion‐exchange properties of this copolymer were studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+, and Hg2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal‐ion uptake involving the measurements of the distribution of a given metal ion between the copolymer 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 copolymer showed a higher selectivity for Fe3+ ions than for Co2+, Zn2+, Cd2+, Pb2+, Cu2+, Ni2+, and Hg2+ ions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 787–790, 2003  相似文献   

7.
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   

8.
Syntheses of urea–melamine–formaldehyde (UMF) resins were studied using 2–12% melamine levels and UF base resins that were preadvanced to various different extents. The melamine reaction was carried out at pH 6.3 with F/(U + M) mole ratio of 2.1 until a target viscosity of V was reached (Gardener–Holdt) and then the second urea added at pH 8.0 to give a final F/(U + M) mole ratio of 1.15. Analyses with 13C‐NMR and viscosity measurements showed that MF components react fast and the UF components very slowly in the melamine reaction. Therefore, as the extent of preadvancement of UF base resin was decreased, the reaction time to reach the target viscosity became longer and the MF resin components showed high degrees of polymerization. The overpolymerization of MF components resulted in increasingly more opaque resins, with viscosity remaining stable for more than a month. As the preadvancement of UF base resin was increased, the extent of advancement of MF components decreased, to give clearer resins, with viscosity slowly increasing at room temperature. Overall, preadvancing the UF base resin components to an appropriate extent was found to be a key to synthesizing various low‐level melamine‐modified UMF resins. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2559–2569, 2004  相似文献   

9.
The adsorption properties, including the adsorption kinetics, adsorption isotherms, and adsorption selectivity, of newly formed chelating resins that contained a heterocyclic functional group and a hydrophilic spacer arm of poly(ethylene glycol) [polystyrene–diethylene glycol–2‐amino‐5‐methylthio‐1,3,4‐thiadizole (PS–DEG–AMTZ) and polystyrene–triethylene glycol–2‐amino‐5‐methylthio‐1,3,4‐thiadizole (PS–TEG–AMTZ)] were studied in detail. The results show that the adsorption kinetics of PS–DEG–AMTZ and PS–TEG–AMTZ for Hg2+ and Ag+ could be described by a pseudo‐second‐order rate equation. The introduction of a spacer arm between the polymeric matrix and functional group was beneficial for increasing the adsorption rates. The apparent activation energies of the resins for Hg2+ and Ag+ were within 20.89–32.32 kJ/mol. The Langmuir model could describe the isothermal process of Hg2+ and Ag+. The competitive adsorption of the resins for Hg2+ and Ag+ in binary mixture systems was also investigated. The results show that Hg2+ and Ag+ were adsorbed before the other metal ions, such as Cu2+, Zn2+, Fe3+, Cd2+, and Pb2+, under competitive conditions. Five adsorption–desorption cycles were conducted for the reuse of the resins. The results indicate that these two resins were suitable for reuse without considerable changes in the adsorption capacity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

10.
Magnetic polymer microspheres composed of magnetite, styrene, and divinylbenzene were prepared by suspension polymerization to produce magnetic ion‐exchange resins (MIEXs). The magnetite was grafted with oleic acid to improve the magnetic properties of the MIEXs and to prevent the magnetite from flushing out of the MIEXs. The shape and magnetic properties of the magnetic microspheres were investigated with scanning electron microscopy and vibrating‐sample magnetometry. The average diameter of the prepared magnetic polymer microspheres was about 219 μm. The two types of MIEXs were prepared, magnetic cation‐exchange resins (MCEXs) and magnetic anion‐exchange resins (MAEXs). MCEX was prepared by sulfonation of magnetic polymer microspheres, and MAEX was made by a quaternization reaction with triethylamine of chloromethylated magnetic polymer microspheres. With diffuse‐reflectance Fourier transform infrared spectroscopy, elemental analysis, and acid–base titration, the degree of substitution and ion‐exchange capacity of the MIEXs were assessed. The efficiency of each MCEX and MAEX for the purification of contaminated water was examined with Co2+ and NO solutions, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2058–2067, 2003  相似文献   

11.
A series of novel snake‐cage resins were synthesized using carboxymethyl chitosan (CM‐CTS) as the snake resin and urea–formaldehyde resin (UF) as the cage resin. Such factors as the optimal synthesis conditions, content of the crosslinking agent, and sorption capacities for metal ions of the above‐mentioned resins were investigated. The experimental results show that these resins have appropriate swelling properties and good mechanical stability. They do not run off in water, HCl, and NaOH aqueous solutions. To form a stable network system, NH4Cl was used as a crosslinking agent to crosslink urea and formaldehyde in synthesis. The sorption experiment showed that the sorption properties of the resins in the presence of the crosslinking agent NH4Cl are better than those without a crosslinking agent. The investigation of the FTIR spectra indicated that the chelate groups, such as —OH, —CO and NHCH2CO, in snake‐resin molecules participated in the coordination with the metal ions, but the —C?O bonds in the cage resin UF did not. The snake resin CM‐CTS in the snake‐cage resins was the major contributor of sorption. The sorption dynamics showed that the sorption was controlled by liquid film diffusion. The isotherms can be described by Freundlich and Langmuir equations. The saturated sorption capacities of the resins for Cu2+, Ni2+, Zn2+, and Pb2+ were 1.48, 0.78, 0.13, and 0.02 mmol g?1, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 310–317, 2002; DOI 10.1002/app.10331  相似文献   

12.
A novel chelating resin was synthesized in just one step under mild synthetic conditions. The synthesis was carried out through the copolymerization of thiosemicarbazide and formaldehyde in an aqueous solution. The adsorption properties for some noble metal ions were investigated. The results showed that the resin had high adsorption selectivity for Au(III) and Ag(I). The adsorption capacities for the two metal ions reached up to 7.3 and 11.8 mmol/g, respectively. The adsorption rate for the two metal ions in a dilute solution was 99.9%. The adsorption fit first‐order kinetics, and an isothermal adsorption study indicated that it corresponded to Langmuir monomolecular layer adsorption. The change in the bonding energy during the chelating process was investigated with X‐ray photoelectron spectroscopy. The study revealed that nitrogen and sulfur atoms of the resins were electron donors and metal ions were electron acceptors in the process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

13.
Terpolymer resins (2‐HAMF) were prepared by the condensation of 2‐hydroxyacetophenone and melamine with formaldehyde in the presence of acid catalyst and using varied molar ratios of reacting monomers. Compositions of terpolymers have been determined by elemental analysis. The number average molecular weights (Mn) have been determined by conductometric titration in nonaqueous medium. Viscometric measurements in dimethyl sulfoxide have been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, infrared and nuclear magnetic resonance spectra were studied to elucidate the structure. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

14.
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   

15.
The polymeric ligand (resin) was prepared from 2‐hydroxy‐4‐methoxybenzophenone with 1,3‐propane diol in the presence of polyphosphoric acid as a catalyst on constant heating at 160°C for 13 h. The poly[(2‐hydroxy‐4‐methoxybenzophenone) propylene] (HMBP‐PD) form 1 : 2 metal/ligand polychelates (metal–polymer complexes) with La(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), and Dy(III). The polymeric ligand and its polychelates (metal–polymer complexes) were characterized on the basis of elemental analyses, electronic spectra, magnetic susceptibilities, IR‐spectroscopy, NMR, and thermogravimetric analyses. The molecular weight was determined using number average molecular weight (Mn) by a vapor pressure osmometry (VPO) method. Activation energy ( E ) of the resin was calculated from differential scanning calorimetry (DSC). All the polychelates are paramagnetic in nature except La(III). Ion‐exchange studies at different electrolyte concentrations, pH, and rate have been carried out for lanthanides(III) metal ions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

16.
An anion‐exchange membrane was prepared by the amination of chlorinated polypropylene and polyethyleneimine at a low temperature and was investigated with respect to not only its physical properties but also its electrochemical properties. The degrees of amination were 50.16, 53.76, 57.11, and 65.29% at 30, 40, 50, and 55°C, respectively. The base polymer membrane had no water uptake, whereas that of the aminated polymer membrane was 0.254, 0.296, 0.298, and 0.319 g of H2O/g of dry membrane, respectively, with increasing amination. The prepared membranes possessed an ion‐exchange capacity in the range of 1.257–2.000 mequiv/g of dry membrane and a fixed ion concentration in the range of 4.492–6.261 mequiv/g of H2O. The ionic conductivity of the aminated polymer membrane was highest when the water uptake was highest. Those of the prepared membrane were in the range of 0.89 × 10?2 to 1.36 × 10?2 S/cm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
Transetherification of methyl ethers of melamine‐formaldehide resins (MER) with monophenyl ethers of ethylene glycol or propylene glycol (ROH) and competing reaction of self‐condensation are studied depending on MER composition (amounts of CH3O? , ? CH2OH, and NH2? groups), ROH type, MER/ROH molar ratio, presence or absence of acid catalysts, and temperature. High rates of self‐condensation processes prevent a complete conversion of CH3O? into RO‐groups. It turned out MER free of methylol groups were not able to be transetherified with high yields due to a premature gelation taking place prior to attaining 50% conversion of methoxy groups (~4 mol/kg) even at low MER/ROH ratios. In contrast, transetherification of MER with methylol groups content up to 3 mol/kg affords the incorporation of RO‐groups into the resin up to 8 mol/kg owing to direct etherification of ? CH2OH groups. The following factors are responsible for the growth of etherified product yield: presence of methylol groups in MER in some amounts without deterioration of MER–ROH compatibilization; CH3O? /ROH molar ratio no higher than 1; primary alcohols (ROH) is more preferable compared to secondary ones; thermal activation of the process is more efficient in comparison with acidic catalysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2977–2985, 2006  相似文献   

18.
Formaldehyde–urea (F/U) reaction products with molar ratios of 1.8, 2.1, and 2.4 were synthesized at pH 8.3, and the last one also at pH 4.5 using 45% formaldehyde aqueous solution. For obtaining the resin, the synthesis of F/U 2.1 was continued by acid‐catalyzed condensation at pH 4.5 and posttreatment with second part of U (F/U 1.05/1) at 70°C and pH 8.3. The products were analyzed using 13C‐NMR spectrometry. Higher excess of F increases the dihydroxymethyl content on account of smaller dimethylene ether content. Certain 13C chemical shifts in carbonyl and methylene region of spectra were assigned to trishydroxymethylurea, being the main trisubstituted urea compound in hydroxymethylated product. Acid catalyst promotes the formation of methylene groups by polycondensation of hydroxymethyl groups, against the background of similar content of dimethylene ethers in both catalytic conditions. The ratio of linear/branched chains is emphasized in characterizing the resin structure. Higher hydroxymethyl content in acid‐catalyzed polycondensation is an advantage of three‐step synthesis technology. The amount of binding methylene and dimethylene ether groups linked only to secondary amino groups can be increased by transhydroxymethylation with subsequent polycondensation in posttreatment with U in suitable reaction conditions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1673–1680, 2006  相似文献   

19.
Iminoamino methylene base intermediates obtained by the decomposition of hexamethylenetetramine (hexamine) stabilized by the presence of strong anions such as SO and HSO, or hexamine sulfate, were shown to markedly improve the water and weather resistance of hardened melamine–urea–formaldehyde (MUF) resins used as wood adhesives and of the wet internal bond strength performance of wood boards bonded with them. The effect was shown to be induced by very small amounts, between 1 and 5 wt % of this material on resin solid content. This strong effect allowed the use of MUF resins of much lower melamine content and also provided good performance of the bonded joints. Because the main effect was also present at the smaller proportion of hexamine as hexamine sulfate, it was not due at all to any increase in the molar ratio of the resin as a consequence of hexamine sulfate addition. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 203–214, 2003  相似文献   

20.
The use of polymeric reagents simplifies the routine acylation of amines because it eliminates traditional purification. In this article, the use of readily available crosslinked poly(4‐vinylpyridine)‐supported benzoyl chloride as an acylating agent of amines in the presence of K2CO3 in n‐hexane is described. The product was readily obtained by the filtration and evaporation of the solvent. The spent polymeric reagent could be regenerated and reused. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

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