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1.
Enzymatic synthesis of a water‐soluble, conducting polyaniline (PANI) was studied, using horseradish peroxidase as the biocatalyst and H2O2 as the initiator, in the presence of a poly(vinylsulfonic acid, sodium salt) (PVS) polyanion template. The effects of the buffer, concentration of H2O2, and the molar ratio of aniline to PVS on the polymerization were particularly investigated. The products were characterized by UV–vis/near‐IR and FTIR spectroscopy, thermogravimetric analysis, and four‐point probe conductivity measurement. The results showed that PVS could be chosen as a new template in the synthesis of PANI. The proper conditions of polymerization were obtained as follows: pH of the buffer was pH 4.0–5.0, the concentration of H2O2 was around 20 mM, and the molar ratio of PVS to aniline was 1–1.5. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 814–817, 2005  相似文献   

2.
Polyesters based on poly(alkyl anhydride), aromatic anhydrides, and polyglycols were synthesized by thermal and catalytic condensation polymerization techniques. The polymerization conditions were optimized by the variation of the monomer concentration, reaction temperature, and so on to achieve the desired properties. The reaction was monitored by the measurement of the acid values at different stages of the polymerization reaction. The water solubility of these polyesters was achieved by the termination of the reaction with the addition of ammonia. These polyester resins were characterized with IR and viscosity measurements. The electrical properties of polyester resins coated and cured on glass cloth were measured with the idea of using them as impregnating varnishes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

3.
Poly(4‐acryloylmorpholine), poly(4‐acryloylmorpholine‐co‐2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid), and poly(2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid) were synthesized by radical polymerization. The water‐soluble polymers obtained, containing tertiary amino, amide, and sulfonic acid groups, were investigated, in view of their metal binding properties, as polychelatogens by using the liquid‐phase polymer‐based retention technique, under different experimental conditions. The metal ions investigated were Ag(I), Cu(II), Co(II), Ni(II), Cd(II), Pb(II), Zn(II), Cr(III), and Al(III). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 180–185, 2006  相似文献   

4.
Water‐soluble high intrinsic viscosity organomontmorillonite modified polyacrylate sodium (OMMT‐modified PNaA) was prepared via an in situ intercalation adiabatic polymerization of sodium acrylate in the presence of OMMT. The FTIR and XRD analyses correspond to the OMMT‐modified PNaA with exfoliated structure of OMMT. The influences of prepared conditions on intrinsic viscosity and dissolving time of the modified polymers had been investigated in this study. It was found that the incorporation of as little as 0.1 wt % of OMMT added to PNaA matrix could be effective to enhance intrinsic viscosity of the modified PNaA. TGA and DSC studies confirmed the enhancement of the thermal stability of the OMMT‐modified PNaA when compared with PNaA. Furthermore, the solution behavior studies of the modified PNaA showed the “antipolyelectrolyte” effect and high “antishearing” property. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

5.
Thermosensitive and water‐soluble copolymers were prepared through the copolymerization of acryloyloxypropyl phosphinic acid (APPA) and N‐isopropyl acrylamide (NIPAAm). The thermosensitivity of the copolymers and copolymer/metal complexes was studied. The APPA–NIPAAm copolymers with less than 11 mol % APPA moiety had a lower critical solution temperature (LCST) of approximately 45°C, but the APPA–NIPAAm copolymers with greater than 21 mol % APPA moiety had no LCST from 25 to 55°C. The APPA–NIPAAm copolymers had a higher adsorption capacity for Sm3+, Nd3+, and La3+ than for Cu2+, Ni2+ and Co2+. The APPA–NIPAAm (10:90) copolymer/metal (Sm3+, Nd3+, or La3+) complexes became water‐insoluble above 45°C at pH 6–7, but the APPA–NIPAAm (10:90) copolymer/metal (Cu2+,Ni2+, or Co2+) complexes were water‐soluble from 25 to 55°C at pH 6–7. The temperature at which both the APPA–NIPAAm copolymers and the copolymer/metal complexes became water‐insoluble increased as the pH values of the solutions increased. The APPA–NIPAAm copolymers were able to separate metal ions from their mixed solutions when the temperature of the solutions was changed; this was followed by centrifugation of the copolymer/metal complexes after the copolymers were added to the metal solutions. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 116–125, 2004  相似文献   

6.
The reaction of poly(ethylene glycol) (PEG, number‐average molecular weight Mn = 400‐2000) and dimethyl 5‐sulfoisophthalate sodium salt (SIPM) synthesized a series of anionic polymeric surfactants having a range of molecular weights. 1H‐NMR, FTIR, and elemental analysis were employed to characterize the structures of these compounds. Also, the influences of the PEG segment lengths of PEG/SIPM copolymers on the surface tension, foaming properties, wetting power, and dispersant properties were investigated. The experimental results indicated that the solution that contained the PEG/SIPM copolymer surfactants exhibited excellent surface‐active properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2727–2731, 2002  相似文献   

7.
BACKGROUND: Emulsions are traditionally formed from two immiscible liquids by mechanical stirring, homogenization, or ultrasonication. For the use of emulsions, stability during storage and transport has been an issue which needs to be addressed. Here, a novel method is proposed to form emulsions instantly by hand shaking from porous polymeric materials. RESULTS: The porous materials were prepared by a freeze‐drying method and then soaked in an oil phase. The oil was absorbed into the micron‐sized pores. The oil‐soaked composites were then placed in water. The dissolution of polymer led to the formation of emulsions by gentle hand shaking within 2 min. Mineral oil, soy oil with drug molecules, and perfluorodecalin were tested as the model oil phases. In each case, stable emulsions with high ratios of oil to water were formed instantly. CONCLUSIONS: A novel route is reported to produce emulsions instantly by hand shaking from porous polymeric materials. Using this method, emulsions could be formed instantly on the site just before application, thus avoiding the cost and stability concerns during transport and storage of emulsions. The method also has the advantages of easy operation and scale‐up possibility. Copyright © 2010 Society of Chemical Industry  相似文献   

8.
A series of novel surfactants containing multianionic and nonionic hydrophilic moieties were prepared by reacting fumaric acid with polyoxyethylenated stearyl ether in the presence of a peroxy‐type free radical initiator to form a carboxylic‐acid‐group‐containing addition product. The structure of these surfactants was confirmed by infrared, nuclear magnetic resonance, and elemental analysis. These surfactants exhibit excellent functional properties of self‐sequestering. This means that besides good surfactant properties, including surface tension, foaming, and wetting, they possess autonomous sequestering ability without any help of additional sequestering agent. When used in cotton bleaching procedures, these surfactants increase the penetration of the fibers of gray fabrics and increase the whiteness of bleached cotton. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3559–3564, 2006  相似文献   

9.
An unsaturated monomer bearing xanthene groups and allyloxyfluorescein (Al‐Flu), was synthesized from fluorescein and allyl bromide by etherification. The structure of the monomer was confirmed by IR and mass spectroscopy and 1H‐NMR, and 13C‐NMR spectroscopy. With azobisisobutyronitrile as a thermal initiator in tetrahydrofuran under 65–70°C, a copolymer of allyloxyfluorescein and acrylamide [poly(Al‐Flu‐co‐AM)] was obtained and was characterized by the methods of IR spectroscopy, ultraviolet–visible spectroscopy, and differential scanning calorimetry. The experimental results show that the fluorescence spectra of water‐soluble poly(Al‐Flu‐co‐AM) was dependent on the pH and temperature in the solution. Moreover, poly(Al‐Flu‐co‐AM) had an excellent linear response between the relative fluorescence intensity and temperature in the range 0–60°C and had a nonlinear response from pH 0.00 to 12.85 between the relative fluorescence intensity and pH. The pH and temperature sensitivities of the fluorescence could be advantageous for it as a multifunctional material to probe pH and temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.  相似文献   

10.
Nobel polymeric adhesion promoter soluble in water was synthesized to improve the adhesion strength of copper lead frame/epoxy molding compound (EMC) joints. N‐(4‐phenolyl)‐(benzotriazole‐5‐carboxylic)amide (PBCA) was synthesized by reacting benzotriazole‐5‐carboxylic acid (CBTA) with 4‐aminophenol. Poly[acrylic‐co‐4‐(5‐benzotriazole)amido phenyl acrylate] (PAB) was synthesized by reacting poly acryloyl chloride with PBCA. The adhesion strength of PAB‐treated copper lead frame/epoxy resin joints increased with the increase of PBCA content in PAB by forming more Cu‐triazole complex. The adhesion strength of PAB‐treated copper lead frame/epoxy resin joints having high PBCA content in PAB (more than 0.3 of mole ratio) is comparable to that of polybenzimidazole (PBI)‐treated copper lead frame/epoxy resin joints. However, the adhesion strength of PAB‐treated copper/epoxy resin joints decreased with the increase of PAB treatment time since Cu‐triazole complex particles were formed on PAB‐treated copper surface and acted as defects. The initial adhesion strength was maintained by suppressing the formation of Cu‐triazole complex particles using PAB having low PBCA contents (0.003 mole ratio of PBCA). The solubility of PAB in water was dependent on the mole ratio of carboxylic acid to PBCA in PAB. The increase of carboxylic acid content in PAB improved the solubility of PAB in water but decreased the adhesion strength with copper. PAB containing 0.03 mole ratio of PBCA was soluble in water. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2202–2210, 2002  相似文献   

11.
A water‐soluble polymer containing phosphonic acid groups was investigated as a polychelatogen by using the liquid‐phase polymer‐based retention technique (LPR) under different experimental conditions. The maximum retention capacity of this polymer was determined at different pHs and polymer–metal ion ratios. The metal ions investigated were Ag(I), Cu(II), Co(II), Ni(II), and Cr(III). The maximum retention capacity values of the divalent metal ions were very similar and higher than those for the trivalent cations, indicating that the polymer–metal ion interaction was basically through electrostatic type. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2917–2922, 2004  相似文献   

12.
A novel series of water‐soluble polyethylene glycol–polydimethylsiloxane (PEG–Silicone) polyesters was prepared by reacting organopolysiloxane with hydroxyl‐terminated polyester. The polyesters are obtained by the polymerization of maleic anhydride (MA) and PEGs (number‐average molecular weights M n = 2000–10,000). FTIR, 1H‐NMR, and elemental analysis were employed to characterized the structures of these compounds. These compounds exhibit good surface activities such as surface tension and low foaming. The influence of the PEG–Silicone polyester surfactants introduced at various concentrations (0.1–2 wt %) was examined by the contact angle method. The measurements performed with various solid substrates indicated that, at comparable concentrations, the PEG–Silicone polyester surfactants were shown to be more efficient for wetting PET and glass. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1236–1241, 2003  相似文献   

13.
A novel water‐soluble, conducting polypyrrole was synthesized by horseradish peroxidase (HRP), in the presence of sulfonated polystyrene, as a polyanionic template. The HRP is an effective catalyst for the oxidative polymerization of pyrrole in the presence of hydrogen peroxide at room temperature. The reaction is sensitive to solution pH and it is performed in pH 2 aqueous solutions. Polymerization of pyrrole by this biological route produced a conducting water‐soluble polypyrrole for the first time. The reaction is benign and in one pot, and the product requires minimal purification. The reversible redox activity of the polypyrrole displays a hystersis loop with pH changes. FT‐IR, UV‐vis absorption spectroscopy, and cyclic voltammetry are used in the characterization of the synthesized polypyrrole. These studies confirm the electroactive and conducting form of polypyrrole, similar to that which has been traditionally synthesized, chemically and electrochemically. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 254–258, 2004  相似文献   

14.
Water‐soluble polymers have attracted much interest due to their potential applications in environmental protection engineering to remove harmful pollutants and in biomedicine in the areas of tissue engineering, within‐body implants or other medical devices, artificial organ prostheses, ophthalmology, dentistry, bone repair, and so on. In this review, particular emphasis is given to the ability of water‐soluble polymers with amine, amide, carboxylic acid, hydroxyl and sulfonic acid functional groups to remove metal ions by means of the liquid‐phase polymer‐based retention (LPR) technique that combines the use of water‐soluble polymers and ultrafiltration membranes. The second part is dedicated to showing the potential application of functional water‐soluble polymers and their polymer–metal complexes as biocides for various bacteria. These polymers and polymer–metal complexes show an efficient bactericide activity, especially to Gram‐negative bacteria, Staphylococcus aureus reaching concentrations lower than 4 µg mL?1. This activity depends on polymer size, type of metal ion, contact time and concentration of polymer and metal ion. The discussion reveals that in the case of the LPR process the efficiency of metal ion removal depends strongly on the type of polymer functional group and the feed pH value. In general, two mechanisms of ion entrapment are suggested: complex formation and electrostatic interaction. In the case of the medical use of water‐soluble polymers and their complexes with metal ions, the review documents the unique bactericide properties of the investigated species. The polymer‐metal ion complexes show a reduced genotoxic activity compared with free metal ions. Copyright © 2009 Society of Chemical Industry  相似文献   

15.
Water‐soluble thermosensitive polymers having phosphonium groups were synthesized by the copolymerization of N‐isopropylacrylamide (NIPAAm) with methacryloyloxyethyl trialkyl phosphonium chlorides (METRs) having varying alkyl lengths. The relative viscosities of the copolymer solutions increased with increasing content of phosphonium groups in the copolymers and decreased with increasing chain length of alkyl chains in the phosphonium groups. However, the copolymers of METR with octyl groups in phosphonium groups (METO) and NIPAAm became water insoluble with increasing contents of METO moieties in the copolymers. The transmittance at 660 nm of the copolymer solutions above the lower critical solution temperature (LCST) decreased gradually with increasing temperature and decreased with increasing chain length of alkyl chains in the phosphonium groups. The transmittance at 660 nm of the copolymer solutions above the LCST was greatly affected by the addition of neutral salts such as KCl. The copolymers of METR with ethyl groups in phosphonium groups and NIPAAm and those of METR with butyl groups in phosphonium groups and NIPAAm had high flocculating abilities against bacterial suspensions. The METO–NIPAAm copolymer was found to have a high antibacterial activity. The flocculating ability and the antibacterial activity of the copolymers were affected by not only the content of phosphonium groups but also the alkyl chain length in the phosphonium groups in the copolymers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 386–393, 2003  相似文献   

16.
New water‐soluble cellulose derivatives containing quaternary ammonium groups were prepared by the heterogeneous reactions of hydroxyethyl cellulose with a quaternary chlorohydrin and characterized by reaction parameters and infrared analyses. The dependence of the heterogeneous reaction on the different affecting factors was studied. The cellulose derivatives obtained were investigated for their property as the water‐soluble polymer for inhibiting the swelling of water‐sensitive clay in oilfields. Based on the kinetic curves for clay hydration swelling, a mathematical model that relates linear clay expansion as a function of hydration rate and hydration equilibrium constant was developed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1416–1422, 2001  相似文献   

17.
New methacrylate monomers containing pendant quaternary ammonium moieties based on 1,4‐diazabicyclo‐[2.2.2]‐octane (DABCO) were synthesized. The DABCO group contains either a butyl or a hexyl pendant group comprising the hydrophobic segment of the monomers and one tether group to the methacrylate moiety. The monomers were homopolymerized in water by using 2,2′‐azobis(2‐methylpropionamide) dihydrochloride (V‐50) as an initiator. The monomers and polymers were characterized by elemental analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), FTIR, and 13C‐NMR. The antimicrobial activities of the corresponding small molecules (bis‐quaternary ammonium monocarboxylates) and polymers were investigated against Staphylococcus aureus and Escherichia coli. Although the small molecules did not show any antimicrobial activity, the polymers were moderately effective against both Gram‐positive and Gram‐negative bacteria. The minimum inhibitory concentration (MIC) values of the polymers with butyl and hexyl hydrocarbon chains against S. aureus and E. coli were found to be 250 and 62.5 μg/mL, respectively. The minimum bactericidal concentration (MBC) value for the polymer with the butyl group was higher than 1 mg/mL, whereas the MBC value for the polymer with hexyl group was found to be 62.5 μg/mL. Thus, an increase of the alkyl chain length from 4 to 6 significantly increased the antimicrobial activity of the polymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 635–642, 2004  相似文献   

18.
The properties of water‐soluble metal–polymers to retain As(III) from aqueous solution are investigated. Poly(acrylic acid)s with different tin contents are prepared. Amounts of 3, 5, 10, and 20 wt % of tin are added to the polymer. The metal compositions are evaluated by thermogravimetry (TG‐DSC) and atomic absorption spectroscopy. Structural properties are analyzed by infrared and 1H nuclear magnetic resonance spectroscopy, and X‐ray diffraction. Additionally, specific surface area was measured using CO2 as adsorbate. Arsenic retention properties are studied using the liquid‐phase polymer‐based retention (LPR) technique. The polymers can bind arsenic species from an aqueous solution in the pH range 4–8. The studies show that the retention capacity is a function of tin content and polymer concentration. At pH 8, the following mol ratios poly(AA)‐Sn : As(III) are analyzed: 600 : 1, 400 : 1, 200 : 1, 100 : 1, and 20 : 1. The highest retention, 80%, is obtained with poly(AA)‐Sn at 10 and 20 wt % of tin at mole ratios 400 : 1, and at nearly to 20 : 1 or 40 : 1 Sn‐As(III). The highest retention is observed at pH 8 and 4. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

19.
N‐Benzyl‐O‐carboxymethyl chitosan (OCChB) was synthesized through a reaction of O‐carboxymethylchitosan (OCCh) and benzaldehyde by the reductive amination method. The chemical structures and physical properties of the derivatives were confirmed by Fourier transform infrared spectroscopy and 1H‐NMR. The cytotoxicity of the polymers was tested by MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide) assay at concentrations ranging from 0.01 to 1000 μg/mL. The substitution degrees of the derivatives, calculated by 1H‐NMR, were 12 and 53% for OCChB1 and OCChB2, respectively. The results show that the derivatives were not toxic at 1000 μg/mL and could decrease the surface tension by concentration on the system surface compared with OCCh. Because of this property, OCChB was applied as a solubility enhancer for triamcinolone (TC), a poorly water‐soluble drug. The polymer solutions at 1.0 mg/mL increased the TC solubility up to 3.5 times for OCChB1 and 5.0 times for OCChB2 compared with its solubility in water. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

20.
A novel water‐soluble polymer was prepared by copolymerization and sulfomethylation using acrylamide (AM) and N‐allylbenzamide (NABI) as raw materials under mild conditions. The effects of ratio of AM to NABI, initiator concentration, reaction temperature, pH, and monomer concentration on the copolymerization were studied. The sulfonates copolymer was characterized by infrared (IR) spectroscopy, 1H NMR spectroscopy, elemental analysis, and atomic force microscopy (AFM). It was found that the sulfonates copolymer could achieve up to 25%, 30% retention rate of the viscosity at a high temperature (120°C) and a vigorous shear condition (1000 s?1). It was also found that the sulfonates copolymer had moderate salt tolerance (NaCl, CaCl2, and MgCl2·6H2O) and its viscosity could be restored to the original value when the shear rate changed from 170 to 510 s?1 and 510 to 170 s?1. At last, the enhanced oil recovery (EOR) of the sulfonates copolymer was tested by core flood, and with up to 10.6% EOR was afforded in presence of 5000 mg/L NaCl brine at 60°C. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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