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1.
Macroporous poly(glycidyl methacrylate‐co‐ethylene glycol dimethacrylate) (PGME) was synthesized by suspension copolymerization and functionalized with diethylene triamine (PGME‐deta). The effect of pH, contact time, and sorbent mass on sorption efficiency of initial and functionalized copolymer sample for removal of Acid Orange 10 dye from aqueous solutions was studied. No dye was sorbed by nonfunctionalized copolymer, indicating that sorption of Acid Orange 10 by PGME‐deta is specific, through amino groups. The isotherm data are best fitted by Langmuir model, indicating homogeneous distribution of active sites in PGME‐deta as well as monolayer sorption. Sorption kinetics study showed that the sorption of Acid Orange 10 by PGME‐deta obeys the pseudo‐second‐order kinetic model. It was shown that PGME‐deta selectively sorbs Acid Orange 10 from binary solution with Bezaktiv Rot reactive dye. The comparison of sorption characteristics of PGME‐deta with activated carbon showed that this functionalized copolymer might be used as an alternative sorbent for textile dyes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

2.
Macroporous copolymers of poly[(glycidyl methacrylate)‐co ‐(ethylene glycol dimethacrylate)] (PGME ) with various crosslinker (ethylene glycol dimethacrylate) concentrations and porosity parameters and additionally functionalized with hexamethylene diamine (PGME‐HD ) were tested as potential Cr(VI ) oxyanion sorbents from aqueous solutions. Kinetics of Cr(VI ) sorption was investigated in the temperature range 298–343 K and the results were fitted to chemical reaction and particle diffusion models. The Cr(VI ) sorption obeys the pseudo‐second‐order model with definite influence of pore diffusion. A temperature rise promotes chromium removal, with a maximum experimental uptake capacity of 4.21 mmol g?1 at 343 K for the sample with the highest amino group concentration. Equilibrium data were analysed with Langmuir, Freundlich and Temkin adsorption isotherm models. Thermodynamic parameters, i.e. Gibbs free energy (ΔG 0), enthalpy (ΔH 0) and entropy change (ΔS 0) and activation energy of sorption (E a), were calculated. The Cr(VI) adsorption onto PGME‐HD was found to be spontaneous and endothermic, with increased randomness in the system. Desorption experiments show that chromium anion sorption was reversible and the PGME‐HD sample GMA 60 HD was easily regenerated with 0.1 mol L?1 NaOH up to 90% recovery in the fourth sorption/desorption cycle. In the fifth cycle, a substantial sorption loss of 37% was observed. © 2016 Society of Chemical Industry  相似文献   

3.
Technetium-99 comprises a significant health risk, since edible plants can bioaccumulate and convert it to more lipophilic species that cannot be excreted through urine. Batch kinetics of pertechnetate removal from aqueous solutions by two samples of crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) functionalized with diethylene triamine (PGME-deta) was investigated at the optimum pH value of 3.0, and the initial solution activity of 325 MBq dm−3. PGME-deta was characterized by elemental analysis, mercury intrusion porosimetry, and scanning electron microscopy. Five kinetic models (pseudo-first, pseudo-second order, Elovich, Bangham, and intraparticle diffusion) were used to determine the best-fit equation for pertechnetate sorption. After 24 h, PGME-deta samples sorbed more than 98% of pertechnetate present, with maximum sorption capacity of 25.5 MBq g−1, showing good potential for remediation of slightly contaminated groundwater.  相似文献   

4.
A poly(glycidyl methacrylate‐co‐ethylene dimethacrylate) polymeric matrix was synthesized, amino‐functionalized and packed to be tested for protein retention and separation. Functionalization was carried out by reacting the epoxy groups with 30% ammonia solution to provide amino groups for anion exchange with proteins. Physical characterization of the particulate material showed that the functionalized polymer is macroporous and exhibits a unimodal pore size distribution. The resin presents good thermal stability. Chromatographic characterization using bovine serum albumin (BSA) and α‐lactalbumin as model proteins showed good retention properties for the amino‐functionalized matrix. The values obtained for the equilibrium constant (K) were around 3 for BSA, both in batch reactor and column‐packed operation mode. The K values for α‐lactalbumin were even higher, 8.01 and 4.65 for the batch and column‐packed experiments, respectively. Finally, axial dispersion coefficients were obtained, with a constant value of 0.0141 cm2s?1 for BSA. Higher values were obtained for α‐lactalbumin, but in this case the axial dispersion coefficient was not constant and its values were dependent on the flows used. © 2001 Society of Chemical Industry  相似文献   

5.
Poly[(diethylaminoethyl methacrylate)‐graft‐(ethylene glycol)] hydrogels were prepared with a molar ratio of 10:1 of diethylaminoethyl methacrylate to poly(ethylene glycol) of number‐average molecular weights (Mn) 200, 400 and 1000 g mol?1 using tetra(ethylene glycol) dimethacrylate to give a crosslinking ratio between 0.5 and 4.0 %. Glucose oxidase and catalase were immobilized in the matrix during polymerization. The maximum enzyme loading used was 6.6 × 10?4 g of glucose oxidase per g of polymer. The equilibrium and dynamic swelling properties of these hydrogels were investigated. The pH‐dependent equilibrium swelling characteristics showed a sharp transition between the swollen and the collapsed state at pH 7.0. The dynamic response of the hydrogel discs to pH was analyzed in pulsatile pH conditions. The effects of particle size, crosslinking and molecular weight of poly(ethylene glycol) (PEG) on the dynamic swelling response were investigated. The pulsatile nature of the response was analyzed using Boltzmann superposition. Swelling–pH master curves were obtained. Copyright © 2004 Society of Chemical Industry  相似文献   

6.
Multiwalled carbon nanotubes (MWCNTs) were functionalized with α,ω‐diamino poly(propylene oxide) (Jeffamine) of different molecular weights and crosslinked with poly(acrylonitrile‐co‐glycidyl methacrylate) [P(AN‐GMA)] to prepare a novel nanocomposite for applications in gel polymer electrolytes (GPEs). The synthesized copolymer was characterized by 1H‐NMR, Fourier transform infrared, and thermal analysis. Scanning electron microscope observation revealed that the Jeffamine‐functionalized MWCNTs distributed uniformly in the nanocomposite membrane. The mechanical behaviors of the nanocomposite membranes were investigated. It was found that the crosslinked nanocomposite membranes of P(AN‐GMA) and Jeffamine‐functionalized MWCNTs exhibited much higher mechanical strength than the counterpart nanocomposite obtained by physical blending. Moreover, the weight content and molecular weights of Jeffamine had an effect on the mechanical properties of the nanocomposites. Differential scanning calorimeter measurements showed that the crosslinked nanocomposite membranes were amorphous. GPEs based on the nanocomposite were prepared and characterized by complex impedance measurements. The GPE based on the nanocomposite of P(AN‐GMA) crosslinked with 6 wt % of MWCNTs functionalized by Jeffamine D400 showed an ionic conductivity of about 3.39 × 10?4 S cm?1 at 25°C, which is much higher than the counterpart nanocomposite of physically blended P(AN‐GMA) and MWCNTs. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

7.
An amino‐functionalized nano‐adsorbent (DETA‐MNPs) was prepared by a process involving: (1) synthesis of superparamagnetic Fe3O4 nanoparticles; (2) introduction of amino groups after which ATRP initiator was anchored; (3) grafting of glycidyl methacrylate (GMA) via SI‐ATRP; and (4) ring‐opening reaction of epoxy groups with diethylenetriamine (DETA). The nano‐adsorbent was characterized by Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), transmission electron microscope (TEM), and vibrating sample magnetometer (VSM) and applied to remove Cu(II) in batch experiments. The effects of pH, Cu(II) concentrations, solution ionic strength, and contact time were investigated. The results show that the DETA‐MNPs are spherical with cubic spine structure, high saturation magnetization (41.9 emu g?1), and an average diameter of 10 nm. The maximum Cu(II) adsorption capacity achieves 83.33 mg g?1 at pH 5.0 by Langmuir model. The adsorption process is highly pH‐dependent and reaches equilibrium within 20 min. Furthermore, the DETA‐MNPs exhibit excellent dispersibility and reusability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 132, 42859.  相似文献   

8.
Two types of porous microparticles based on glycidyl methacrylate, dimethacrylic monomers (ethylene glycol dimethacrylate, diethylene glycol dimethacrylate and triethylene glycol dimethacrylate) and gellan were prepared by two methods. The first method was aqueous suspension polymerization in the presence of N‐butyl acetate as porogenic agent when the crosslinking and grafting reactions were achieved in a single step. The second method was based on the reaction between hydroxyl groups belonging to gellan and the epoxy groups situated on the surface of porous microparticles based on glycidyl methacrylate and dimethacrylic monomers in basic medium. The microparticles with and without gellan were characterized by Fourier transform infrared spectroscopy, SEM, AFM and TGA. Also, the porous structure was investigated in terms of pore volume, porosity and specific surface. The swelling behaviour in aqueous solution with different pH values as well as sorption studies of cefuroxime sodium salt onto porous microparticles were investigated. The presence of gellan in the structure of the microparticles leads to porous materials characterized by higher specific surface areas (Ssp = 78–140 m2 g–1), higher swelling capacities (Sw = 162%–365%) and higher sorption capacities of the drug (qe = 101–147 mg g–1) compared to microparticles without gellan in their structures (Ssp = 73–85 m2 g–1; Sw = 139%–209%; qe = 70–110 mg g–1). © 2019 Society of Chemical Industry  相似文献   

9.
Molecularly imprinted polymers (MIP) with high performance in selectively recognizing bisphenol A (BPA) were prepared by using a novel and facile surface molecular‐imprinting technique. Vinyl‐functionalized, monodispersed silica spheres were synthesized by a one‐step emulsion reaction in aqueous solution. Then, BPA surface molecularly imprinted polymers (SMIP) were prepared by polymerization with 4‐vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. Maximal sorption capacity (Qmax) of the resulting SMIP was up to 600 μmol g?1, while that of nonimprinted polymers was only 314.68 μmol g?1. Kinetic binding study showed that sorption capacity reached 70% of Qmax in 20 min and sorption equilibrium at 80 min. SMIP had excellent accessibility and affinity toward BPA, for the selectivity coefficients of SMIP for BPA in respect to phenol, p‐tert‐butylphenol, and o‐phenylphenol were 3.39, 3.35, and 3.02, respectively. The reusage process verified the SMIP owning admirably stable adsorption capacity toward BPA for eight times. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

10.
《溶剂提取与离子交换》2013,31(4-5):515-524
ABSTRACT

The loading kinetics of TcO4 ? from water and 1?M NaOH solution to macroporous polymer (MPP) impregnated with 2-nitrophenyl octyl ether (NPOE) are reported. The loading process can be simply expressed as: -ln (1 - [TcO4 ?]MPP / [TcO4 ?]MPP,e) =k t +A, where [TcO4 ?]MPP and [TcO4 ?]MPP,e respectively refer to the pertechnetate concentration in the MPP phase at time t and the equilibrated value, and A is a constant. With TcO4 ? in water and in 1?M NaOH as loading solutions, the overall mass transfer coefficients k are estimated to be 0.058?min?1 and 0.067?min?1 and the saturated loading capacities of TcO4 ? are 8.0 × 10?8?mol/g wet MPP and 5.6 × 10?8?mol/g wet MPP, respectively. TcO4 ? can be easily stripped from loaded MPP by >1?M HNO3 solution. Loading-stripping cycling and breakthrough experiments demonstrate a good performance of NPOE-impregnated MPP, in particular with TcO4 ?-containing water as the loading feed.  相似文献   

11.
Poly(2‐hydroxyethyl methacrylate‐co‐glycidyl methacrylate) p(HEMA–GMA) membrane was prepared by UV‐initiated photopolymerisation of 2‐hydroxyethyl methacrylate (HEMA) and glycidyl methacrylate (GMA) in the presence of an initiator, azobisisobutyronitrile (AIBN). Cholesterol oxidase was immobilised directly on the membrane by forming covalent bonds between its amino groups and the epoxide groups of the membrane. An average of 53 µg of enzyme was immobilised per cm2 of membrane, and the bound enzyme retained about 67% of its initial activity. Immobilisation improved the pH stability of the enzyme as well as its temperature stability. The optimum temperature was 5 °C higher than that of the free enzyme and was significantly broader. The thermal inactivation rate constants for free and immobilised preparations at 70 °C were calculated as ki (free) 1.06 × 10?1 min?1 and ki (imm) 2.68 × 10?2 min?1, respectively. The immobilised enzyme activity was found to be quite stable in the repeated experiments. © 2002 Society of Chemical Industry  相似文献   

12.
In this article, we report the preparation of crosslinked epoxy microspheres with diameters of 5–10 μm prepared via phase‐inverted phase separation induced by polymerization in the thermosetting blend of epoxy and poly(ε‐caprolactone). The surfaces of the epoxy microspheres were functionalized to bear 2‐bromopropionyl groups, which were further used as initiators to obtain poly(glycidyl methacrylate) (PGMA) grafted epoxy microspheres via the surface‐initiated atom transfer radical polymerization approach. The PGMA‐grafted epoxy microspheres were then employed to react with 3‐aminopropyltrimethoxylsilane (APTMS) to obtain the functionalized epoxy microspheres, the surface of which contained a great number of trimethoxysilane groups. A co‐sol–gel process between the APTMS‐functionalized epoxy microspheres and tetraethoxysilane was performed, and organic–inorganic glassy solids were obtained. The organic–inorganic glasses were used as precursors for accessing macroporous silica materials via pyrolysis at elevated temperatures. The hierarchical porosity of the resulting macroporous silica was investigated by means of field emission scanning electronic microscopy, transmission electronic microscopy, and surface‐area Brunauer–Emmett–Teller (BET) measurements. We found that the macroporous silica possessed BET surface areas in the range 183.9–235.2 m2/g, depending on the compositions of their precursors. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

13.
《分离科学与技术》2012,47(16):2406-2412
A new sulfonamide containing polymeric sorbent for the removal of mercury ions from waste waters was prepared starting from poly(glycidyl methacrylate)-b-poly(ethylene glycol)-b-poly(glycidyl methacrylate) (PGMA- b -PEG- b -PGMA) triblock copolymer prepared by using the ATRP method. Epoxy groups on the block copolymer were functionalized with amino groups. Ammonia-functionalized PGMA- b -PEG- b -PGMA was treated with excess of benzenesulfonyl chloride to obtain a sulfonamide-based polymeric sorbent. The sulfonamide containing the polymeric sorbent with a 3.5 mmol · g?1 total nitrogen content is able to selectively sorb mercury from aqueous solutions. The mercury sorption capacity of the resin is around 3.12 mmol g?1 under non-buffered conditions. Experiments performed in identical conditions with several metal ions revealed that Cd(II), Pb(II), Zn(II), Fe(III), and Fe(II) also were extractable in quantities (0–0.45 mmol/g). The sorbed mercury can be eluted by repeated treatment with 4 M HNO3 without hydrolysis of the sulfonamide groups.  相似文献   

14.
Two crosslinkable second‐order nonlinear optical polymers were prepared by copolymerization of 2,3,4,5,6‐pentafluorostyrene, styrene (St), glycidyl methacrylate (GMA) and 1‐(4‐nitrophenyl)‐2‐(4‐{[2‐(methacryloyloxy) ethyl] ethylamino}‐phenyl) diazene (DR1M) via the sealed‐tube reaction technique. These polymers were characterized using 1H, 13C and 19F NMR spectroscopy, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The crosslinkable polymers have high molecular weights, good organosolubility, excellent film‐forming properties and high glass transition (106–110 °C) and thermal decomposition temperatures (290–350 °C) after being crosslinked. Furthermore, the polymer films possess not only high values (12–16 pm V?1) of electro‐optical coefficient (r33) at 1.3 µm wavelength but also low optical loss (1.7 dB cm?1) at 1.55 µm wavelength, which is of interest for applications in electro‐optical devices. Copyright © 2004 Society of Chemical Industry  相似文献   

15.
Monodisperse nonporous crosslinked poly(glycidyl methacrylate) (PGMA) particles with immobilized metal affinity ligands were prepared for selective recovery of proteins. The PGMA particles, with an average size of 2.2 µm, were prepared by a simple dispersion polymerization of glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA). The particles were characterized by scanning electron microscopy (SEM) and Fourier‐transform infrared spectroscopy (FTIR). The epoxy groups of the particles were modified with the metal chelating agent iminodiacetic acid (IDA), which forms metal–IDA chelates at the active sites. After charging with copper ions, the particles were used to recover a model protein, bovine hemoglobin (BHb), in a batchwise manner. The particles had the adsorption capacity of 218.7 mg g−1 with little nonspecific adsorption. The adsorption behavior could be described with the Langmuir equation. The effect of pH on the adsorption was also studied. Regeneration of the metal‐chelated particles was easily performed with 50 mmol L−1 ethylenediaminetetraacetic acid (EDTA), followed by washing with water and reloading with Cu2+. The particles could be very useful as an affinity separation adsorbent. Copyright © 2005 Society of Chemical Industry  相似文献   

16.
《分离科学与技术》2012,47(5):1083-1090
Abstract

Aqueous solutions of water‐structuring, kosmotropic salts (e.g., salts of PO4 3?, HPO4 2?, CO3 2?) will salt‐out water‐destructuring chaotropic ionic liquids (ILs) (e.g., 1‐butyl‐3‐methylimidazolium chloride, ([C4mim]Cl)) forming salt/salt aqueous biphasic systems (ABS). The chaotropic pertechnetate (TcO4 ?) anion will partition without the use of an extractant into the IL‐rich phase. These complex salt/salt ABS are not unlike the complex and salt‐rich Hanford tank waste, and thus have been used here as a simple model to show effectiveness in the partitioning of TcO4 ? from such tank waste into an IL‐rich phase.  相似文献   

17.
This report describes the preparation and swelling behaviour of novel hydrogels based on a water‐soluble dimethacrylate monomer (EBisEMA), which is characterized by a relatively high molar mass (Mn ~ 1700 g mol?1) and contains a high proportion of aliphatic ether bonds in its structure. This feature results in moderately crosslinked and flexible polymer networks. Significant differences were observed in degree of swelling, depending on the synthesis method employed to obtain the hydrogels. The equilibrium water sorption of EBisEMA photopolymerized in bulk was 68 wt% while that of EBisEMA photopolymerized in aqueous solution (0.5 g mL?1) was 104 wt%. Thiol–methacrylate hydrogels were prepared by visible light photopolymerization of EBisEMA with a tetrafunctional thiol (PETMP) at various EBisEMA‐to‐PETMP molar ratios. These hydrogels contained unreacted thiol groups because of a faster homopolymerization reaction of EBisEMA. Hydrogels were also prepared in bulk by propylamine‐catalysed Michael addition reaction. No significant differences in swelling were observed between EBisEMA homopolymer and photocured EBisEMA–PETMP copolymer. Conversely, a marked increase in water uptake (110 wt%) was observed in the EBisEMA–PETMP hydrogels prepared by the Michael addition reaction catalysed by propylamine. These trends are explained in terms of a balance between the mass fraction of hydrophilic groups and the crosslinking density of the network. EBisEMA–PETMP hydrogels formulated with thiol in excess showed a noticeable tendency to adhere to diverse substrates, including paper, metals, glass and skin. This feature makes them especially attractive in applications for which adhesion is particularly critical such as dermatological patches. © 2018 Society of Chemical Industry  相似文献   

18.
A novel process for the production of superabsorbent materials (hydrogels) from bacterial cellulose (BC) was developed. Prior to crosslinking with a water‐soluble polyethylene glycol diacrylate (PEGDA), BC was first carboxymethylated and functionalized with glycidyl methacrylate. The degree of crosslinking influenced the swelling properties of the hydrogels. The use of greater amounts of PEGDA enhanced the formation of a thicker macromolecular network containing fewer capillary spaces in the crosslinked gel. The maximum water retention value of the hydrogels containing 2.5–3.5 mmol of carboxyl groups per gram of gel reached 125 g g?1 in distilled water, and 29 g g?1 in saline (0.9% NaCl solution). The highly porous hydrogel architecture with a pore size of 350–600 µm created a high specific surface area. This enables rapid mass penetration in superabsorbent applications. The superabsorbent hydrogels reached 80% of their maximum water absorption capacity in 30 min. © 2018 Society of Chemical Industry  相似文献   

19.
Poly(GMA/MMA) beads were synthesized from glycidyl methacrylate (GMA) and methyl methacrylate (MMA) in the presence of a cross‐linker (i.e. ethyleneglycol dimethacrylate) (EGDMA) via suspension polymerization. The epoxy groups of the poly(GMA/MMA) beads were converted into amino groups with either ammonia or 1,6‐diaminohexane (i.e. spacer‐arm). An L ‐histidine ligand was then covalently immobilized on the aminated (poly(GMA/MMA)‐AH) and/or the spacer‐arm attached (poly(GMA/MMA)‐SAH) beads using glutaric dialdehyde as a coupling agent. Both affinity adsorbents were used in human serum albumin (HSA) adsorption/desorption studies under defined pH, ionic strength or temperature conditions in a batch reactor. The spacer‐arm attached affinity adsorbent resulted in an increase in the adsorption capacity to HSA when compared to the aminated counterpart (i.e. poly(GMA/MMA)‐AH). The maximum adsorption capacities of the affinity adsorbents were found to be significantly high, i.e. 43.7 and 80.2 mg g?1 (of the beads), while the affinity constants, evaluated by the Langmuir model, were 3.96 × 10?7 and 9.53 × 10?7 mol L?1 for poly(GMA/MMA)‐AH and poly(GMA/MMA)‐SAH, respectively. The adsorption capacities of the affinity adsorbents were decreased for HSA by increasing the ionic strength, adjusted with NaCl. The adsorption kinetics of HSA were analysed by using pseudo‐first and pseudo‐second‐order equations. The second‐order equation fitted well with the experimental data. Copyright © 2005 Society of Chemical Industry  相似文献   

20.
Two cycles of sorption/desorption of water or ethanol by light‐cured dental resins of bisphenol A glycol dimethacrylate (Bis‐GMA), bisphenol A ethoxylated dimethacrylate (Bis‐EMA) urethane dimethacrylate (UDMA) triethylene glycol dimethacrylate and decanediol dimethacrylate (D3MA) were studied. The experimental curves mt = f(t) taken for the first water sorption by poly‐Bis‐GMA, poly‐Bis‐EMA and poly‐UDMA showed a maximum. A maximum was also observed in the curve obtained for first sorption of ethanol by poly‐Bis‐GMA. In all other cases, the curves for sorption or desorption of water or ethanol showed Fickian behavior. The experimental data obtained for first sorption of water or ethanol were perfectly fitted to a new proposed equation, which predicts water or ethanol sorption with simultaneous extraction of unreacted the monomer. This equation gave us the possibility for the determination of the diffusion coefficient of the extraction of the unreacted Bis‐GMA during the water and ethanol sorption, as well as the diffusion coefficient of the extraction of the unreacted Bis‐EMA and UDMA during the water sorption. The maximum water or ethanol absorbed at equilibrium and the diffusion coefficient are determined from the second sorption/desorption cycle during which the extraction of the monomer is negligible. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

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