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1.
The precipitation polymerization of aniline in the presence of organic acids, including toluene‐4‐sulfonic acid, phenylphosphonic acid, 4‐aminophenylphosphonic acid, and acetophosphonic acid, led in one step to conductive polyaniline. The polyaniline showed very good affinity for water and was easily modified to be water‐soluble. In comparison with the widely studied postpolymerization of doped polyaniline, this reaction allowed reasonably good conductivity to be achieved at a lower acid/polyaniline ratio. Moreover, the easy in situ incorporation of the dopant into the polymer structure caused high stability of the created salt; that is, no dedoping was observed after it was washed with water, methanol, or other solvents. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3562–3569, 2002  相似文献   

2.
Summary: The oxidative polymerization of N‐glucosylaniline was carried out using ammonium persulfate as the oxidant in phosphate buffer. The structure of the isolated polymer was determined by 1H NMR, 13C NMR, and UV‐vis spectroscopy to be the polyaniline having glucose residues attached to the general polyaniline unit. Participation of the ortho‐position of the aromatic ring in the polymerization was also confirmed by the analyses.

The oxidative polymerization of N‐glucosylaniline.  相似文献   


3.
A series of water‐soluble N‐substituted poly(alkylanilines) (PNAAs) have been enzymatically synthesized with a variety of groups, from methyl to n‐butyl, such as poly(N‐methylaniline), poly(N‐ethylaniline), poly(N‐butylaniline) and poly(N‐phenylethanolamine). The syntheses were made in the presence of poly(4‐sodium styrene sulfonate) (SPS) as a template and horseradish peroxidase (HRP) as a catalyst. The size and type of the groups have a great effect on the properties of the final polymers. UV‐vis spectroscopy and cyclic voltammetry measurements confirmed that for enzymatically synthesized PNAAs/SPS complexes, the electroactivity increased with the bulkiness of the substituents. These polymers have been studied in the doped and undoped states by FT‐IR and UV‐vis spectroscopy. Also these polymers show multiple and reversible optical transitions that can be ascribed to the formation of polaron and bipolaron states. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

4.
A new electron‐donating polymer composed of a vinylogous tetrathiafulvalene (TTF) unit was prepared by the oxidative dimerization of 1,4‐bisdithiafulvenyl‐2,5‐didodecyloxybenzene using iodine. The polymer was soluble in common organic solvents such as CHCl3 and toluene. The number‐average molecular weight of the polymer with dodecyloxy group was 24,900 determined from GPC. The UV–vis spectrum of the polymer showed the absorption maxima at 587, 712, and 803 nm, which are due to a cation radical of the vinylogous TTF unit in the polymer. The reduction of the polymer to its neutral state was performed using sodium hydrogen sulfite. The structure of the polymer was confirmed by 1H NMR and UV–vis spectra compared with that of a dimer model compound prepared by oxidation of 1‐dithiafulvenyl‐2,5‐didodecyloxybenzene using iodine. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4600–4608, 2005  相似文献   

5.
Ten hydrophobic, substituted, acetylene monomers were examined as to their abilities to form an inclusion complex with hydroxypropyl‐β‐cyclodextrin (HPCD). Only the monomers with suitable substitutents were found to form the monomer/HPCD complex, which was identified by NMR, FTIR, and UV‐vis spectroscopy. Polymerizations of the monomers were successfully carried out in aqueous solution by using the prepared monomer/HPCD inclusion complex and by using a water‐soluble Rh‐based catalyst, [Rh(cod)2BF4] or [Rh(nbd)(H2O)OTs]. Such polymerizations provided high‐yield (>90%) polymers with a cis content of approximately 100%. The as‐prepared polymers could take an ordered helical conformation, just like their counterparts obtained in organic solvents.

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6.
Copolymers were synthesized through the chemically oxidative polymerization of N‐ethylaniline (EA) and aniline (AN) in five acid aqueous media. The polymerization yield, intrinsic viscosity, molecular weight, solubility, solvatochromism, electrical conductivity, and mechanical properties of the copolymer films were systematically studied through changes in the comonomer ratio, polymerization temperature, oxidant, oxidant/monomer ratio, and acid medium. Open‐circuit‐potential and temperature measurements of the polymerization solutions showed that the polymerization rate depended on the EA content, and the polymerization was an exothermic reaction. The resultant copolymers were characterized in detail with IR, ultraviolet–visible, and 1H NMR spectroscopy, gel permeation chromatography, wide‐angle X‐ray diffractometry, and scanning electron microscopy. The reactivity ratios of the monomer pair were calculated from the 1H NMR spectra of the copolymers formed at a low conversion. The polymers exhibited good solubility and interesting solvatochromism in most of the solvents and variable conductivity with the EA/AN ratio and doping state. The conductivity of the HCl‐doped copolymers increased monotonically from 5.61 × 10?7 to 2.55 × 10?1 S/cm with decreasing EA content from 100 to 0 mol % and showed a percolation transition between EA concentrations of 20 and 30 mol %. The EA/AN copolymers also had excellent film formability and flexibility together with high mechanical and oxygen‐enriching properties. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6109–6124, 2004  相似文献   

7.
Well‐defined star polymers consisting of tri‐, tetra‐, or octa‐arms have been prepared via coupling‐onto strategy using photoinduced copper(I)‐catalyzed 1,3‐dipolar cycloaddition click reaction. An azide end‐functionalized polystyrene and poly(methyl methacrylate), and an alkyne end‐functionalized poly(ε‐caprolactone) as the integrating arms of the star polymers are prepared by the combination of controlled polymerization and nucleophilic substitution reactions; whereas, multifunctional cores containing either azide or alkyne functionalities were synthesized in quantitatively via etherification and ring‐opening reactions. By using photoinduced copper‐catalyzed azide–alkyne cycloaddition (CuAAC) click reaction, reactive linear polymers are simply attached onto multifunctional cores to form corresponding star polymers via coupling‐onto methodology. The chromatographic, spectroscopic, and thermal analyses have clearly demonstrated that successful star formations can be obtained via photoinduced CuAAC click reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1687–1695  相似文献   

8.
9.
Water‐soluble 2N2O–Cu(II) complexes were synthesized and used for the catalytic oxidation of benzylic alcohols to the corresponding aldehydes in pure water resulting in high yields of up to 94%. Importantly, the catalytic system exhibits a wide substrate scope, high functional group tolerance and can be reused directly for subsequent reaction cycles. Using this catalytic system, the product 4‐methylbenzaldehyde can be produced on a multi‐gram scale and in the complete absence of any organic solvent, surfactant or phase transfer reagent. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

10.
We report the synthesis of a water‐soluble diblock copolymer composed of polysulfonic diphenyl aniline (PSDA) and poly(ethylene oxide) (PEO), which was prepared by reacting an amine‐terminated PSDA and tosylate PEO (PEO‐Tos). First, a HCl‐mediated polymerization of sulfonic diphenyl aniline monomer with the formation of HCl‐doped PSDA was carried out. After its neutralization and reduction, a secondary amine‐functionalized PSDA was obtained. Second, PEO‐Tos was synthesized via the tosylation of the monohydroxyl PEO methyl ether with tosylol chloride. Diblock copolymers with various PEO segment lengths (PSDA‐b‐PEO‐350 and PSDA‐b‐PEO‐2000) were obtained with PEO‐350 [number‐average molecular weight (Mn) = 350] and PEO‐2000 (Mn = 2000). The prepolymers and diblock copolymers were characterized by Fourier transform infrared spectroscopy, NMR, mass spectrometry, and ultraviolet–visible light. They had relatively low conductivities, ranging from 10?6 to 10?3 S/cm, because of the withdrawing effect of the sulfonic group as well as the steric effects of the bulky aromatic substitutuents at the N sites of the polyaniline backbone and of the PEO block. These polymers were self‐doped, and an intermolecular self‐doping was suggested. The external doping was, however, more effective. The self‐doping induced aggregation in water among the PSDA backbones, which was also stimulated by the presence of hydrophilic PEO blocks. Furthermore, the electrical conductivities of the diblock copolymers were strongly temperature‐dependent. PSDA‐b‐PEO‐2000 exhibited about one order of magnitude increase in conductivity upon heating from 32 to 57 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2179–2191, 2004  相似文献   

11.
Random regioregular copolymers of 3‐hexylthiophene and 3,4‐ethylenedioxythiophene were synthesized by grignard metathesis polymerization. Soluble copolymers were obtained with a high degree of regioregularity and with a monomer ratio close to the feed ratio. A comparison between the optical properties and the thin film morphologies of these copolymers and poly(3‐hexylthiophene) is also presented. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

12.
Uniform one‐dimensional V2O5@polyaniline core/shell nanobelts have been fabricated by a simple in‐situ polymerization method in the absence of any surfactant and additional initiator. The influences of pH and additional initiator on the morphology of the resulting products are investigated. The pH value is important for the formation of V2O5@polyaniline core/shell nanobelts, which preserve the original morphology of V2O5 nanobelts. With a decrease in the pH value to 0 the original morphology of the V2O5 nanobelts is destroyed. When ammonium peroxydisulfate is used, some separated polyaniline nanofibers are formed. The formation of the V2O5@polyaniline core/shell nanobelts can be related to the in‐situ polymerization of aniline monomer by etching V2O5 nanobelts. The electrochemical lithium intercalation/deintercalation of V2O5@polyaniline core/shell nanobelts is investigated by cyclic voltammograms.

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13.
Polyaniline (PAni) grafted nano silica were synthesized successfully by in situ polymerization of aniline (An) using ammonium persulphate (APS) as oxidant by three procedures: Firstly, γ‐(2,3‐epoxypropoxy)propyltrimethoxysilane (EPTMS) reacted with nano silica. Secondly, the EPTMS modified nano silica reacted with An as an initiator site introduced onto the silica surface, and finally PAni grafted silica was obtained by in situ chemical oxidative An. The chemical grafting of PAni was confirmed by FTIR and UV–Vis. The percentages of grafting EPTMS and An onto nano silica were 24.5 wt% and 10.3 wt%, respectively, calculated from elemental analysis (EA), while the percentage of grafting PAni was 157.7 wt% as a mass ratio of the grafting PAni and charged nano silica, investigated by TGA. In addition, characteristic agglomerate morphology of PAni was observed in the composite by SEM. The electrical conductivity of the product was 2.6 × 10?6 S cm?1 and it manifested that the resulted product was a typical semiconductor. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

14.
15.
The polymerization of methyl methacrylate (MMA) initiated by the system lysozyme, copper(II) chloride, and water was carried out. The effect of the amount of each component on the conversion of MMA was studied. The polymerization proceeded through a radical mechanism. Urea, known to be a denaturing agent for protein, was able to promote the polymerization. On addition of urea, it was found that the following three reactions took place: (1) promotion of the polymerization of MMA with lysozyme, Cu(II) ion, and water by the unfolding of the third structure of lysozyme, (2) polymerization initiated by urea and Cu(II) ion, (3) polymerization initiated by the S-S bonds of lysozyme and urea.  相似文献   

16.
Two series of terpolymers, one of o‐/m‐toluidine and aniline with o‐aminobenzoic acid and the other of o‐/m‐toluidine and aniline with m‐aminobenzenesulfonic acid, have been synthesized by oxidative polymerization via an emulsion method with ammonium persulfate as the oxidant and HCl as the external dopant. The terpolymers exhibit excellent solubility and retain the high conductivity (∼1 S cm−1) characteristic of the unsubstituted homopolymer, polyaniline. The terpolymers also possess higher thermal stability than polyaniline. This can be attributed to the presence of internal doping groups and substituents, which introduce flexibility to the otherwise rigid polyaniline backbone. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3040–3048, 2005  相似文献   

17.
Summary: The first π‐conjugated poly(thioketene dimer) was synthesized via the homopolymerization of a silylthioketene dimer by a chemical oxidation‐reduction process. The polymerization of trimethylsilylthioketene dimer in the presence of FeCl3 (in CHCl3 at 70 °C for 24 h) gave the corresponding doped poly(thioketene dimer). After treatment of the doped polymer with an aqueous solution of ammonia, the neutral poly(thioketene dimer) was obtained with an incidental desilylation. The polymer obtained was soluble in DMF and DMSO. From gel permeation chromatographic analysis (DMF, polystyrene standards), the number‐average molecular weight of the polymer was found to be 7 460. The polymer showed low oxidation potentials derived from the thioketene dimer unit. An effective extension of the π‐conjugation was observed in the polymer.

Synthesis of π‐conjugated poly(thioketene dimer).  相似文献   


18.
Conductive composites consisted of epoxy resin and polyanilines (PANIs) doped with dodecylbenzenesulfonic acid ( 1 ), dodecylsulfonic acid (2), di(2‐ethylhexyl)sulfosuccinic acid (3), and HCl were synthesized by use of Ntert‐butyl‐5‐methylisoxazolium perchlorate (5) under various reaction conditions. It was found that the composites with PANI doped with acid 2 (PANI‐2) prepared by curing with 10 mol % of reagent 5 at 80 °C for 12 h showed high electroconductivity along with the low conducting percolation threshold (3 wt % of PANI‐2). Furthermore, the composite with even ?10 wt % of PANI‐2 exhibited ?10?1 S/cm of electroconductivity. The UV–vis and IR measurements indicated that the conductive emeraldine salt form of PANI‐2 in the composite was maintained after the curing reaction. The thermal stability was studied by TGA and DSC measurements, and then, the Td10 and Tg of the composite with 5 and 10 wt % of PANI‐2 were found to be similar to those with the cured epoxy resin itself. In addition, the similar investigation with an oxetane resin instead of the epoxy resin was also carried out. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 718–726, 2006  相似文献   

19.
Zero‐valent palladium complex, Pd(PTh3)3, with three tri(2‐thienyl)phosphine ligands was prepared and characterized. Pd(PTh3)3 is superior to Pd(PPh3)4 in catalyzing Suzuki‐Miyaura coupling and polymerization of thiophene‐based derivatives. The Suzuki polycondensation of 3‐hexyl‐5‐iodothiophene‐2‐boronic pinacol ester with Pd(PTh3)3 as the catalyst precursor afforded high‐molecular‐weight P3HT with high regularity and yield. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4556–4563, 2008  相似文献   

20.
The efficient formation of low polydispersity core cross‐linked star (CCS) polymers via controlled/living radical polymerization (LRP) and the arm‐first approach was found to be dependant on the mediating catalyst system. The Ru catalyst, Ru(Ind)Cl(PPh3)2 Cat. 1 , and tertiary amine co‐catalyst were used to synthesize highly living poly(methyl methacrylate) (PMMA) macroinitiators, which were then linked together with ethylene glycol dimethacrylate (EGDMA) to form PMMAarmPEGDMAcore CCS polymers. The quantitative and near‐quantitative synthesis of CCS polymers were observed for low to moderate molecular weight macroinitiators ( = 8 and 20 kDa), respectively. Lower conversions were observed for high‐molecular weight macroinitiators ( ≥ 60 kDa). Overall, an improvement of between 10 and 20% was observed when comparing the Cat. 1 system to a conventional Cu‐catalyzed system. This significant improvement in macroinitiator‐to‐star conversion is explained in the context of catalyst system selection and CCS polymer formation.

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