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1.
Crosslinked copolymers of acrylamide (AA) and ethylacrylate and some ion exchangers derived from them containing either primary amine groups, obtained by the Hofmann degradation of the amide groups, or carboxylic groups, obtained by the alkaline hydrolysis of the ester groups, were studied. Divinylbenzene and N,N′‐methylenebisacrylamide were used as crosslinkers. The starting copolymers and the corresponding ion exchangers were characterized by IR spectroscopy, swelling behavior, and thermogravimetric analysis. The ion‐exchanger properties were correlated with the crosslinker nature and the chemical reactions performed on the AA copolymers. The average molecular weight between two crosslinks, determined from the swelling data in water, was compared with that calculated on the basis of the copolymerization stoichiometry only for the carboxylic cation exchangers. In this way, the preservation of the crosslink density after the hydrolysis was revealed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2701–2707, 2003  相似文献   

2.
Chloromethylated polystyrene was chemically modified through alkylation of pyridylazo‐β‐naphthol (PAN) in the presence of a phase‐transfer catalyst. The chemical modification was achieved through O‐alkylation as well as N‐alkylation of PAN, leading to formation of polymer‐supported quaternary ammonium salt in the latter case. Both types of a polymer‐supported PAN moiety were detected by FTIR spectroscopic analysis. The complexation behavior of the polymer‐supported PAN as an ion‐exchanger toward some metal ions was studied. Thermogravimetric and differential thermogravimetric analyses data were used to study the kinetics of the thermal decomposition process of the ion‐exchanger. Some thermodynamic parameters for the ion‐exchanger were calculated by applying the rate theory of the first‐order reaction. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3044–3048, 2000  相似文献   

3.
A silica‐sphere–poly(catechol hexamethylenediamine) (PCHA–SiO2) composite was prepared via the one‐step facile polymerization of catechol and hexamethylenediamine; this method uses a silica sphere as a hard template. The chemical structures and morphologies of this composite were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and transmission electron microscopy. The adsorption experiments indicated that the PCHA–SiO2 composite served as a very attractive adsorbent for Pb(II)‐, Cu(II)‐, and Cd(II)‐ion removal at lower concentrations and had very good selective adsorption abilities for Pb(II) and Cu(II) ions in a solution contaminated with these three ions at higher concentrations. These interesting results may have been due to the reversible H+ adsorption–desorption properties of the characteristic phenol amine structure of the PCHA–SiO2 composite. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45839.  相似文献   

4.
Functional emulsifier‐free cationic latexes based on styrenic monomer vinylbenzyl chloride (VBC) and acrylic monomer 2‐(dimethylamino)ethyl methacrylate (DMA) were successfully prepared with dual quaternary ammonium ions (36–63 mol %) on both monomer moieties in two‐stages. First, [2‐(methacryloyloxy)ethyl]dimethylhexadecylammonium bromide monomer (DMA(C16)), prepared via quaternization of DMA with 1‐bromohexadecane, was utilized as a comonomer (5–20%) as well as a surfactant in the emulsion polymerization of VBC. Next, the quaternization of chloromethyl groups in the VBC moiety in latex particles with trimethylamine and N,N‐dimethylhexadecylamine created a second type of quaternized sites on the latex particles. The percentages of the quaternary ammonium ions of the first‐stage latexes (P[VBC‐DMA(C16‐x)]) and the second‐stage latexes (P[VBC(R)‐DMA(C16‐x)]) were determined using bromide and chloride ion‐selective electrodes. The particles were characterized with a scanning electron microscope, Zetasizer, measuring water contact angles of their pellets. The polymer structure and the alkyl group length in their quaternary ammonium ions played an important role on the sizes, zeta potentials and hydrophilic–hydrophobic balances of the latexes. The water contact angles of the pellets of the latex particles varied from 50.3 to 109.6° depending on both the polymer structure and the alkyl group length. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42775.  相似文献   

5.
Atom transfer radical polymerization of n‐butyl methacrylate (BMA) was conducted in an aqueous dispersed system with different kinds of copper complexes. The partitioning behavior of the copper complexes, including CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipydine (dNbpy), CuCl2/dNbpy, CuCl/2,2′‐bipydine (bpy), CuCl2/bpy, CuCl/bis(N,N′‐dimethylaminoethyl)ether (bde), and CuCl2/bde between the monomer (BMA), and water was studied in detail with ultraviolet‐visible spectroscopy. The results show that with a less hydrophobic ligand, such as bpy or bde, most of the Cu(I) or the Cu(II) complexes migrated from the BMA phase to the aqueous phase, the atom transfer equilibrium was destroyed, and the polymerization was nearly not controlled; it converted to classical emulsion polymerization. As to the very hydrophobic ligand dNbpy, although the partitioning study of the copper complexes indicated that not all the copper species were restricted to the organic phase, the linear correlation between the molecular weight and the monomer conversion and the narrow polydispersities confirmed that the polymerization was still quite well controlled. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3175–3179, 2003  相似文献   

6.
An amine‐ester derivative of isoeugenol was prepared in three steps. This amine‐ester was converted to diazonium salt and subsequently was reacted with 2‐naphthol and a novel isoeugenol ester‐azo derivative as a new monomer was obtained in quantitative yield. This monomer was characterized by high‐field 1H‐NMR, IR, and elemental analysis and then was used for the preparation of model compound and polymerization reactions. 4‐Phenyl‐1,2,4‐triazoline‐3,5‐dione was allowed to react with this new monomer. The reaction was very fast and gave only one double adduct by Diels–Alder and ene pathways in excellent yield. The polymerization reactions of novel monomer with bistriazolinediones [bis(p‐3,5‐dioxo‐1,2,4‐triazolin‐4‐ylphenyl)methane and 1,6‐bis(3,5‐dioxo‐1,2,4‐triazolin‐4‐yl)hexane] were carried out in N,N‐dimethylacetamide at room temperature. The reactions were exothermic, fast, and gave novel heterocyclic polyimides by repetitive Diels–Alder‐ene polyaddition reactions. Some structural characterization and physical properties of these novel heterocyclic polyimides are reported. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1942–1951, 2003  相似文献   

7.
A series of copolymers, poly(acrylamide)‐co‐poly(N,N‐dimethylaminoethyl methacrylate)‐co‐poly(N‐cetyl DMAEMA) (abbreviation PDAMCn), was synthesized with different monomer ratios. The resulting copolymer solution shows pronounced viscosity–response property which is CO2‐triggered and N2‐enabled. Electrical conductivity experiment shows that tertiary amine group on DMAEMA experiences a protonate and deprotonate transition upon CO2 addition and its removal. In addition, different incorporation rates of DMAEMA leads to two kinds of morphological change in the presence of CO2 and thus induces different rheological behaviors. PDAMCn incorporating longer hydrophobic monomer (C18DM) show more pronounced initial viscosity and higher critical stress required to cause network deformation, which consequently enhances the viscosity–response property of the solution. The addition of NaCl could also tune the viscosity of PDAMCn solution. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41468.  相似文献   

8.
The reaction of the Cu(II) bis N,O‐chelate‐complexes of L‐2,4‐diaminobutyric acid, L‐ornithine and L‐lysine {Cu[H2N–CH(COO)(CH2)nNH3]2}2+(Cl)2 (n = 2–4) with terephthaloyl dichloride or isophthaloyl dichloride gives the polymeric complexes {‐OC–C6H4–CO–NH–(CH2)n–CH(nh2)(COO)Cu(OOC)(NH2)CH–CH2)n–NH‐}x 1 – 5 . From these the metal can be removed by precipitation of Cu(II) with H2S. The liberated ω,ω′‐N,N′‐diterephthaloyl (or iso‐phthaloyl)‐diaminoacids 6 – 10 react with [Ru(cymene)Cl2]2, [Ru(C6Me6)Cl2]2, [Cp*RhCl2]2 or [Cp*IrCl2]2 to the ligand bridged bis‐amino acidate complexes [Ln(Cl)M–(OOC)(NH2)CH–(CH2)nNH–CO]2–C6H4 11 – 14 .  相似文献   

9.
The aim of this research work was a thermodynamic and kinetic study of the retention of Cr(VI) ions from a K2CrO4 solution on macroporous weak‐ and strong‐base anion exchangers, Lewatit M 64 A and Lewatit MP 500 A, respectively. Also, the correlations among the ion‐exchange rate, the retention capacity of Cr(VI), and some process parameters were established. The parameters studied mainly were the concentration of Cr(VI) ions and the type of the counterions coupled with active groups from the anion exchangers. The results led to the conclusion that, for the Lewatit M 64 A resin, there is the following order of the Cr(VI) retention capacity: RCl > R2SO4 > ROH, while for the strong‐base anion exchanger, the retention capacity for the Cr(VI) ions is different: ROH > RCl > R2SO4. In the Cl? form, both anion exchangers have the same retention‐capacity values. On the other side, the weak‐base anion exchanger in SO and OH? forms presents the lowest retention‐capacity values. The process kinetics also presents some differences: for the Lewatit M 64 A resin, the ion‐exchange rate has lower values, especially in the OH? form. This result is attributed to the increase of the OH? ion concentration in the solution and its presence hinders the dissociation of the active groups of a weak‐base anion exchanger. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2093–2098, 2002  相似文献   

10.
Epoxy resin–silica nanocomposites with spherical silica domains with 29.0 nm in diameter in an epoxy resin matrix were synthesized from Bisphenol‐A type epoxide monomer, 2,2‐bis(4‐glycidyloxyphenyl)propane (DGEBA), and perhydropolysilazane (PHPS, ? [Si2? NH]n? ). The volume fraction of silica domain in the composite varied from 5.4 to 37.8 vol % by varying the feed ratio of PHPS to the epoxide monomer. The reaction mechanism of epoxy group and PHPS was investigated by using glycidyl methacrylate as a model compound of the epoxy monomer by 1H‐nucular magnetic resonance and Fourier transform infrared spectrometry. Ammonia gas provided by the decomposition of PHPS with moisture converted PHPS to silica and cured the epoxy monomer. The curing of epoxy monomer preferably proceeded than the conversion of silica. The addition of 1,4‐diaminobutane drastically accelerated the rate of curing; white and hard epoxy resin–silica nanocomposites were obtained. The good thermal stability of the composite prepared with DGEBA/PHPS/1,4‐diaminobutane was observed by thermogravimetric analysis. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

11.
Functionalised SBA‐15 mesoporous silica with polyamidoamine groups (PAMAM‐SBA‐15) was successfully prepared with the structure characterised by X‐ray diffraction, nitrogen adsorption–desorption, Fourier transform infrared spectra and thermogravimetric analysis. PAMAM‐SBA‐15 was applied as adsorbent for Cu(II), Pb(II) and Cd(II) ions removal from aqueous solution. The effects of the solution pH, adsorbent dosage and metal ion concentration were studied under the batch mode. The Langmuir model was fitted favourably to the experimental data. The maximum sorptive capacities were determined to be 1.74 mmol g?1 for Cu(II), 1.16 mmol g?1 for Pb(II) and 0.97 mmol g?1 for Cd(II). The overall sorption process was fast and its kinetics was fitted well to a pseudo‐first‐order kinetic model. The mean free energy of sorption, calculated from the Dubinin–Radushkevich isotherm, indicated that the sorption of lead and copper, with E > 16 kJ mol?1, followed the sorption mechanism by particle diffusion. The adsorbent could be regenerated three times without significant varying its sorption capacity. A series of column tests were performed to determine the breakthrough curves with varying bed heights and flow rates. The breakthrough data gave a good fit to the Thomas model. Maximum sorption capacity of 1.6, 1.3 and 1.0 mmol g?1 were found for Cu(II), Pb(II) and Cd(II), respectively, at flow rate of 0.4 mL min?1 and bed height of 8 cm, which corresponds to 83%, 75% and 73% of metallic ion removal, respectively, which very close to the value determined in the batch process. Bed depth service time model could describe the breakthrough data from the column experiments properly. © 2012 Canadian Society for Chemical Engineering  相似文献   

12.
The retention process of the Cu(II) and Ni(II) cations from CuSO4 and NiSO4 aqueous solutions by eight acrylic ion exchangers was studied. Also, the elution process of these cations with 0.5 mol · L−1 HCl solution was analyzed. The quantitative retention and elution as well as the development aspects of the two processes were observed by the column method. Seven ion exchangers contained weak base, weak acid, and amphoteric functional groups, these being known as chelating agents. Also, an ion exchanger with carboxylic groups, as a model, was taken in this study. The experiments show that the ion exchangers can be divided in three types as follows: (a) bad chelating agents; (b) chelating ion exchangers with the limited efficiency; (c) ion exchangers with good chelating properties and a high application efficiency; especially, the ion exchanger with hydroxamic functional groups is considered in this class. Also, the experimental data prove that, both for Cu(II) and Ni(II) cations, the volume of the purified effluent is higher than the HCl volume needs for their complete elution. This fact means concentration of the metal cations in the liquid phase. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1387–1394, 1999  相似文献   

13.
The liquid‐crystalline (LC) monomer 4‐allyoxybenzoyloxy‐4′‐buthylbenzoyloxy‐p‐phenyl (M1), whose LC phase appeared at lower temperatures, from 137 to 227°C, and the modified mesogenic monomer 4‐allyoxybenzoyloxy‐4′‐methyloxybenzoyloxy‐p‐biphenyl (M2), whose LC phase appeared at higher temperatures, from 185 to 312°C, were prepared. A series of side‐chain LC polysiloxanes containing M1 and M2 were prepared by graft copolymerization. Their LC properties were characterized by differential scanning calorimetry, thermogravimetric analysis, polarizing optical microscopy, and X‐ray diffraction. The results show that the introduction of the modified mesogenic monomer M2 into the polymeric structure caused an additional increase in the clearing point (isotropic transition temperature) of the corresponding polysiloxanes, compared with unmodified polysiloxanes, but did not significantly affect the glass‐transition temperature. Moreover, the modified polysiloxanes exhibited nematic phases as the unmodified polymer did. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1196–1201, 2005  相似文献   

14.
Polypyrrole Th(IV) phosphate, an electrically conducting ‘organic‐inorganic’ cation‐exchange composite material was prepared by the incorporation of an electrically conducting polymer, i.e., polypyrrole, into the matrix of a fibrous type inorganic cation‐exchanger thorium(IV) phosphate. The composite cation‐exchanger has been of interest because of its good ion‐exchange capacity, higher chemical and thermal stability, and high selectivity for heavy metal ions. The temperature dependence of electrical conductivity of this composite system with increasing temperatures was measured on compressed pellets by using four‐in‐line‐probe dc electrical conductivity measuring instrument. The conductivity values lie in the semiconducting region, i.e., in the order of 10?6 to 10?4 S cm?1 that follow the Arrhenius equation. Nernst–Plank equation has been applied to determine some kinetic parameters such as self‐diffusion coefficient (D0), energy of activation (Ea), and entropy of activation (ΔS*) for Mg(II), Ca(II), Sr(II), Ba(II), Ni(II), Cu(II), Mn(II), and Zn(II) exchange with H+ at different temperatures on this composite material. These results are useful for predicting the ion‐exchange process occurring on the surface of this cation‐exchanger. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

15.
New polymer colloids based on the saccharide monomer, using of 3‐O‐methacryloyl‐1,2:5,6‐di‐O‐isopropylidene‐α‐D ‐glucofuranose (3‐MDG), were prepared by semicontinuous emulsion polymerization, a widely used industrial process. The copolymerization of 3‐MDG and butyl acrylate (BA), by the monomer‐addition technique, at 70°C, using sodium persulfate (Na2S2O8) as an initiator, was investigated. The influence of some reaction parameters, such as the type and concentration of the surfactants as well as the monomer addition rate (Rm) on the polymerization rate (Rp), the colloidal properties, and the stability of the latexes, was studied. It was found that under starved‐feed conditions the polymerization rate and the particle size (D) increased with an increasing rate of monomer addition. The weight‐average molecular weight (M w) also increased by enhancing Rm and a narrower molecular weight distribution was obtained. Furthermore, the type and the concentration of the surfactants strongly influenced the particle size and its distribution. The effect of the seed stage on the particle size and its distribution was also investigated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2091–2102, 2003  相似文献   

16.
The free‐radical copolymerization of methyl methacrylate (MMA) with NP‐tolylmalemide (NPTMI) at 77°C in cyclohexanone solution initiated by AIBN was studied. The copolymer composition was calculated from the nitrogen content estimated by the Mico–Kijedldahl's method and by elemental analysis. The reactivity ratios have been calculated by Fineman and Ross method. The monomer reactivity ratios were rNPTMI = 1.24, rMMA = 2.1. The glass transition temperature (Tg) of the copolymers were determined by torsion braid analysis (TBA). The thermal stability was determined by thermogravimetric analysis (TGA). T50, temperature at which the weight loss reaches 50%, was abstained. The results showed that the M n and M w increased, whereas the NPTMI feed content increased. The Tg and T50 increased dramatically. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 867–870, 2004  相似文献   

17.
In this study, 9‐(4‐nitrophenylsulfonyl)‐9H‐carbazole (NPhSCz) monomer was chemically synthesized. The monomer characterization was performed by Fourier transform infrared spectroscopy, 1H‐NMR, and melting point analysis. Two different electropolymerizations of NPhSCz were studied on a gold microelectrode (Au electrode) and carbon fiber microelectrodes (CFMEs) in a 0.1M sodium perchlorate (NaClO4)/acetonitrile solution. The electropolymerization experiments were done from 1 to 4 mM. The characterizations of two different modified electrodes of poly[9‐(4‐nitrophenylsulfonyl)‐9H‐carbazole] [poly(NPhSCz)] were performed by various techniques, including cyclic voltammetry, scanning electron microscopy–energy‐dispersive X‐ray analysis, and electrochemical impedance spectroscopy (EIS). The effects of the initial monomer concentrations (1, 2, 3, and 4 mM) were examined by EIS. The capacitive behaviors of the modified electrodes were defined via Nyquist, Bode magnitude, Bode phase, and admittance plots. The variation of the low‐frequency capacitance (CLF) and double‐layer capacitance (Cdl) values are presented at different initial monomer concentrations. Poly(NPhSCz)/CFME was more capacitive (CLF = 6.66 F/cm2 and Cdl ≈ 28 mF) than the Au electrode (CLF = 6.53 F/cm2 and Cdl ≈ 20 mF). An equivalent circuit model of R[QR(CR)(RW)](CR), (R: Current, Q: Constant phase element, C: Double layer capacitance, W: Warburg impedance), was used to fit the theoretical and experimental data. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

18.
O‐Hydroxypropyl‐N‐butyl chitosan (C4‐HPCS) was prepared by microwave irradiation and phase‐transfer catalysis; this consisted of two steps: (1) the synthesis of O‐hydroxypropyl chitosan (HPCS) with chitosan and propylene oxide and (2) the synthesis of C4‐HPCS with HPCS and 1‐butyl bromide. The results of the experiment are as follows: Fourier transform infrared spectroscopy and 1H‐NMR displayed the characteristic peaks of C4‐HPCS, thermogravimetric analysis showed that C4‐HPCS was stable until 240°C, the critical micelle concentration was 0.025 wt %, the surface tension was equal to 65.70 ± 0.09 mN/m, the hydrophile–lipophile balance number value was 13.55, and the emulsifying power, foaming expansion, and foaming volume stability were 73.10, 45, and 94 wt %, respectively. This indicated that C4‐HPCS had superior surface performance and more excellent hydrophilicity. In addition, the microwave irradiation and phase‐transfer catalysis used in the experiment were considered to be more environmentally friendly and time‐saving methods. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41527.  相似文献   

19.
Methyl methacrylate (MMA) was successfully grafted onto rubber‐wood fiber in a free‐radical solution polymerization initiated by ferrous ion and hydrogen peroxide. The effects of the reaction parameters (reaction temperature, reaction period, influence of hydrogen peroxide, ferrous ammonium sulfate, and monomer concentrations) were investigated. The grafting percentage showed dependency on H2O2, Fe2+, and monomer concentrations, as well as reaction temperature and reaction period. The optimum reaction temperature was determined to be about 60°C and the reaction period was 60 min. The optimum concentration of H2O2 was 0.03M and optimum amounts of Fe2+ and MMA were 0.26 mmol and 2.36 × 10?2 mol, respectively. Poly(methyl methacrylate) (PMMA) homopolymer was removed from the graft copolymer by Soxhlet extractor using acetone. The presence of PMMA on the fiber was shown by FT‐IR spectroscopy and gravimetric analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2499–2503, 2003  相似文献   

20.
Graft copolymers of 4‐vinyl pyridine (4‐VP) synthesized by using simultaneous gamma irradiation method were further functionalized by post polymer quaternization reactions at N: of the pyridine ring of the graft copolymers. Using the optimum grafting conditions reported earlier for the grafting of 4‐VP onto extracted cellulose, graft copolymer was synthesized in bulk and was further functionalized by quaternization with hexyl bromide (C6H13Br), benzyl chloride (C6H5CH2Cl), n‐butyl bromide (C4H9Br), and maleic anhydride (MAnh). The quaternized polymers were studied for treatment of hardness of water, antibacterial action, emulsification properties, metal ion uptake and stability toward thermal degradation, and enzymatic and alkaline hydrolysis to evaluate the suitability of these polymers in harsh chemical, microbial, and thermal environments. The functionalized polymers were also characterized for surface morphology (SEM), elemental analysis and FTIR for investigations of structural aspects, and to obtain evidence for quaternization. The functionalized copolymers exhibit a range of properties that can be used in many fields of water purification technologies including antibacterial agents and ion exchangers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2454–2464, 2004  相似文献   

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