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1.
This article reports the synthesis and characterization of copolymers based on aniline and substituted anilines by using dodecylbenzene sulfonic acid as a dopant. The copolymers were soluble in organic solvents, such as methanol, ethanol, isopropanol, N‐methylpyrrolidinone, dimethylsulphoxide, and have conductivity of the order of 1.5 to 10?7 S/cm depending upon the monomer ratios and extent of dopant used. The effect of substituents like 2‐methyl, 2‐ethyl, and 2‐isopropyl groups on the electrochemical, conductivity, thermal stability, solubilization, and spectroscopic behavior of the copolymers has been evaluated. The composition of the copolymers was determined by 1H‐NMR spectroscopy. Corrosion inhibition behavior of the copolymers in 1.0N HCl has been evaluated using linear polarization resistance method and Tafel extrapolation method. The corrosion efficiency depends upon the copolymer composition and it increased with increasing amount of 2‐alkyl aniline in the feed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

2.
In this study, the synthesis of polypyrrole‐b‐vinyl aniline modified cyclohexanone formaldehyde resin (PPy‐b‐CFVAnR) block copolymers by a combination of condensation polymerization and chemical oxidative polymerization processes was examined. First, a cyclohexanone formaldehyde resin containing vinyl aniline units [4‐ vinyl aniline modified cycl?ohexanone formaldehyde resin (CFVAnR)] was prepared by a direct condensation reaction of 4‐vinyl aniline and cyclohexanone with formaldehyde in an in situ modification reaction. CFVAnR and pyrrole (Py) were then used with a conventional method of in situ chemical oxidative polymerization. The reactions were carried out with heat‐activated potassium persulfate salt in the presence of p‐toluene sulfonic acid in a dimethyl sulfoxide–water binary solvent system; this led to the formation of desired block copolymers. The effects of the oxidant–monomer molar ratio, dopant existence, addition order of the reactants, and reaction temperature on the yield, conductivity, and morphology of the resulting products were investigated. PPy‐b‐CFVAnR copolymers prepared with a resin‐to‐Py molar ratio of 1:40 showed conductivity in the range 3.7 × 10?1 to 3.8 × 10?2 S/cm. Oxidant‐to‐Py molar ratios of 0.5 and 1.0 were proposed to be the optimum stoichiometries for higher conductivity and yield, respectively, of the copolymer. The morphology of the copolymer (PPy‐b‐CFVAnR) was investigated with environmental scanning electron microscopy analyses. The results indicate that the surface of the copolymer was composed of well‐distributed nanospheres with average particle diameters of 60–85 nm. Also, the synthesized PPy‐b‐CFVAnR had a higher thermal stability than the pure CFVAnR. The chemical composition and structure of the PPy‐b‐CFVAnR copolymers were characterized by Fourier transform infrared spectroscopy and measurement. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 132, 42841.  相似文献   

3.
The commercial use of polyaniline has been impeded by its intractable nature and insolubility. The use of substituted polyaniline has been attempted mainly to increase the processibility of polyaniline, but this approach usually results in the lowering of the conductivity. This study reports the synthesis of poly(1‐naphthylamine), a fused ring derivative of polyaniline, and its copolymers with aniline and o‐toluidine via a chemical polymerization method. Spectral, thermal, morphological, and conductivity studies were carried out to elucidate the influence of the incorporation of aniline and o‐toluidine units into poly(1‐naphthylamine). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

4.
The electrochemical polymerization of aqueous solution of aniline and HCl was carried out in a single compartment electrochemical cell. After 2 h of the polymerization reaction, polarity of the electrodes was reversed and kept for 1 h. By this process the conductivity of the polyaniline (PAni) formed was found to increase dramatically from 1.1 × 10?4 to 3.0 × 10?1 S/cm. The PAni samples obtained both by reversing the polarity (“PANI‐R”) and without reversing the polarity (“PANI”) were characterized by the infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), ultraviolet spectroscopy (UV), Hall effect experiment, X‐ray analysis (XRD) and scanning electron microscope (SEM). The results show that the increase in the conductivity of PAni through the reversion of polarity is due to the partial reduction of over oxidized sample giving more emeraldine base and hence more polaron formation with increased charge carrier density and its mobility. The degree of crystallinity and the crystallite size is decreased marginally and the d‐spacing is increased marginally due to this reduction. The PAni behaves like a p‐type semiconductor that means the majority current carriers are holes. A plausible reduction mechanism due to reversal of polarity during electrochemical polymerization is also proposed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   

5.
Poly(2‐aminobenzoic acid) and poly(3‐aminobenzoic acid) were synthesized by chemical polymerization of the respective monomers with aqueous 1M hydrochloric acid and 0.49M sodium hydroxide, using ammonium persulfate as an oxidizing agent. In addition, polymerization in an acid medium was carried out in the presence of metal ions, such as Cu(II), Ni(II), and Co(II). Poly(2‐aminobenzoic acid‐co‐aniline) and poly(3‐aminobenzoic acid‐co‐aniline) were synthesized by chemical copolymerization of aniline with 2‐ and 3‐aminobenzoic acids, respectively, in aqueous 1M hydrochloric acid. The copolymers were synthesized at several mole fractions of aniline in the feed and characterized by UV–visible and FTIR spectroscopy, the thermal stability, and the electrical conductivity. Metal ions, such as Cu(II), Ni(II), and Co(II), were incorporated into homo‐ and copolymers by the batch method. The percentage of metal ions in the polymers was higher in the copolymers than in the homopolymers. The thermal stability of the copolymers increased as the feed mole fraction of aniline decreased and varied with the incorporation of metal ions in the polymers. The electrical conductivity of the homo‐ and copolymers was measured, which ranged between 10?3 and 10?10 S cm?1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2641–2648, 2003  相似文献   

6.
Poly(epichlorohydrin‐g‐styrene) and poly (epichlorohydrin‐g‐methyl methacrylate) graft copolymers were synthesized by a combination of cationic and photoinitiated free‐radical polymerization. For this purpose, first, epichlorohydrin was polymerized with tetrafluoroboric acid (HBF4) via a cationic ring‐opening mechanism, and, then, polyepichlorohydrin (PECH) was reacted ethyl‐hydroxymethyl dithio sodium carbamate to obtain a macrophotoinitiator. PECH, possessing photolabile thiuram disulfide groups, was used in the photoinduced polymerization of styrene or methyl methacrylate to yield the graft copolymers. The graft copolymers were characterized by 1H‐NMR spectroscopy, differential scanning calorimetry, and gel permeation chromatography. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

7.
A poly[(R,S)‐3‐hydroxybutyrate] macroinitiator (PHB‐MI) was obtained through the condensation reaction of poly[(R,S)‐3‐hydroxybutyrate] (PHB) oligomers containing dihydroxyl end functionalities with 4,4′‐azobis(4‐cyanopentanoyl chloride). The PHB‐MI obtained in this way had hydroxyl groups at two end of the polymer chain and an internal azo group. The synthesis of ABA‐type PHB‐b‐PMMA block copolymers [where A is poly(methyl methacrylate) (PMMA) and B is PHB] via PHB‐MI was accomplished in two steps. First, multiblock active copolymers with azo groups (PMMA‐PHB‐MI) were prepared through the redox free‐radical polymerization of methyl methacrylate (MMA) with a PHB‐MI/Ce(IV) redox system in aqueous nitric acid at 40°C. Second, PMMA‐PHB‐MI was used in the thermal polymerization of MMA at 60°C to obtain PHB‐b‐PMMA. When styrene (S) was used instead of MMA in the second step, ABCBA‐type PMMA‐b‐PHB‐b‐PS multiblock copolymers [where C is polystyrene (PS)] were obtained. In addition, the direct thermal polymerization of the monomers (MMA or S) via PHB‐MI provided AB‐type diblocks copolymers with MMA and BCB‐type triblock copolymers with S. The macroinitiators and block copolymers were characterized with ultraviolet–visible spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography, cryoscopic measurements, and thermogravimetric analysis. The increases in the intrinsic viscosity and fractional precipitation confirmed that a block copolymer had been obtained. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1789–1796, 2004  相似文献   

8.
Copolymers (P(PDA/Ar)) of o‐phenylenediamine with aniline (Ar = ANi), 3,4‐ethylenedioxythiophene (Ar = EDOT) and 2,3,5,6‐tetrafluoroaniline (Ar = TFANi) were synthesized via polycondensation initiated by ammonium persulfate. The NH2 group content in the copolymers was determined by analyzing the 1H NMR spectra of the N‐acetylated copolymers. Copolymers crosslinked by viologen (1,1'‐disubstituted 4,4'‐bipyridinium dichloride) were obtained by reaction involving the reactive NH2 groups in the copolymers. The absorption wavelengths of solutions of the copolymers and the electrochemical oxidation and reduction potentials of cast films of the copolymers were affected by the electrical properties of the Ar unit. © 2016 Society of Chemical Industry  相似文献   

9.
Microphase separation behavior on the surfaces of poly(dimethylsiloxane)‐block‐poly(2,2,3,3,4,4,4‐heptafluorobutyl methacrylate) (PDMS‐b‐PHFBMA) diblock copolymer coatings was investigated. The PDMS‐b‐PHFBMA diblock copolymers were successfully synthesized via atom transfer radical polymerization (ATRP). The chemical structure of the copolymers was characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy. Surface composition was studied by X‐ray photoelectron spectroscopy. Copolymer microstructure was investigated by atomic force microscopy. The microstructure observations show that well‐organized phase‐separated surfaces consist of hydrophobic domain from PDMS segments and more hydrophobic domain from PHFBMA segments in the copolymers. The increase in the PHFBMA content can strengthen the microphase separation behavior in the PDMS‐b‐PHFBMA diblock copolymers. And the increase in the annealing temperature can also strengthen the microphase separation behavior in the PDMS‐b‐PHFBMA diblock copolymers. Moreover, Flory‐Huggins thermodynamic theory was preliminarily used to explain the microphase separation behavior in the PDMS‐b‐PHFBMA diblock copolymers.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

10.
Diblock copolymers, poly[(10‐hydroxydecanoic acid)‐block‐styrene] (PHDA‐b‐PSt), were synthesized by combining enzymatic condensation polymerization of HDA and atom transfer radical polymerization (ATRP) as of St PHDA was first obtained via enzymatic condensation polymerization catalyzed by Novozyme‐435. Subsequently, one terminus of the PHDA chains was modified by reaction with α‐bromopropionyl bromide and the other terminus was protected by chlorotrimethylsilane. The resulting monofunctional macroinitiator was used subsequently in ATRP of St using CuCl/2,2′‐bipyridine as the catalyst system to afford diblock copolymers including biodegradable PHDA blocks and well‐defined PSt blocks. Polymeric nanospheres were prepared by self‐assembly of the PHDA‐b‐PSt diblock copolymers in aqueous medium. Copyright © 2008 Society of Chemical Industry  相似文献   

11.
Poly(o‐amino benzyl amine), poly(m‐amino benzyl amine), and the copolymers with aniline were synthesized in 10?4M HCl by using ammonium persulfate as oxidizing agent. The copolymers were synthesized at various feed mole fractions of comonomer diamine and characterized by elemental analysis, FTIR, 1H‐NMR spectroscopy, and electrical conductivity. The polymerization yield depended on the substituent position in the aromatic ring. Copper ion was incorporated in the polymers and the amount depended on the side groups position in the aromatic ring. The thermal stability increased when copper ions and aniline units were incorporated in the polymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 31–36, 2004  相似文献   

12.
In this study, four different Schiff bases namely 4,4′‐oxybis[N‐(2‐hydroxybenzilidene)aniline] (2‐HBA), 4,4′‐oxybis[N‐(4‐hydroxybenzilidene)aniline] (4‐HBA), 4,4′‐oxybis[N‐(3,4‐dihydroxybenzilidene)aniline] (3,4‐HBA), and 4,4′‐oxybis[N‐(4‐hydroxy‐3‐methoxybenzilidene)aniline] (HMBA) were synthesized. These Schiff bases were converted to their polymers that have generate names of poly‐4,4′‐oxybis[N‐(2‐hydroxybenzilidene)aniline] (P‐2‐HBA), poly‐4,4′‐oxybis[N‐(4‐hydroxybenzilidene)aniline] (P‐4‐HBA), poly‐4,4′‐oxybis[N‐(3,4‐dihydroxybenzilidene)aniline] (P‐3,4‐HBA), and poly‐4,4′‐oxybis[N‐(4‐hydroxy‐3‐methoxybenzilidene)aniline] (PHMBA) via oxidative polycondensation reaction by using NaOCl as the oxidant. Four different metal complexes were also synthesized from 2‐HBA and P‐2‐HBA. The structures of the compounds were confirmed by FTIR, UV‐vis, 1H and 13C NMR analyses. According to 1H NMR spectra, the polymerization of the 2‐HBA and 4‐HBA largely maintained with C? O? C coupling, whereas the polymerization of the 3,4‐HBA and HMBA largely maintained with C? C coupling. The characterization was made by TG‐DTA, size exclusion chromatography and solubility tests. Also, electrical conductivity of the polymers and the metal complex compounds were measured, showing that the synthesized polymers are semiconductors and their conductivities can be increased highly via doping with iodine ions (except PHMBA). According to UV–vis measurements, the optical band gaps (Eg) were found to be 3.15, 2.06, 3.23, 3.02, 2.61, 2.47, 2.64, 2.42, 2.83, 2.77, 2.78, and 2.78 for 2‐HBA, P‐2‐HBA, 4‐HBA, P‐4‐HBA, 3,4‐HBA, P‐3,4‐HBA, HMBA, PHMBA, 2‐HBA‐Cu, 2‐HBA‐Co, P‐2‐HBA‐Cu, and P‐2‐HBA‐Co, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

13.
In this study, poly(o‐anisidine) [POA], poly(o‐anisidine‐co‐aniline) [POA‐co‐A], and polyaniline [PANi] were chemically synthesized using a single polymerization process with aniline and o‐anisidine as the respective monomers. During the polymerization process, p‐toluene sulfonic acid monohydrate was used as a dopant while ammonium persulfate was used as an oxidant. N‐methyl‐pyrolidone (NMP) was used as a solvent. We observed that the ATR spectra of POA‐co‐A showed features similar to those of PANi and POA as well as additional ones. POA‐co‐A also achieved broader and more extended UV–vis absorption than POA but less than PANi. The chemical and electronic structure of the product of polymerization was studied using Attenuated Total Reflectance spectroscopy (ATR) and UV–visible spectroscopy (UV–vis). The transition temperature of the homopolymers and copolymers was studied using differential scanning calorimetry and the viscosity average molecular weight was studied by using dilute solution viscometry. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

14.
The copolymerization of ethylene and 1,7‐octadiene was carried out to synthesize polyethylene with unreacted vinyl groups. The prepared copolymer [poly (ethylene‐co‐1,7‐octadiene) (PEOD)] was epoxidized with peracetic acid, m‐chloroperbenzoic acid, or formic acid/H2O2. Of these, peracetic acid gave the best results. Epoxidized PEOD was subjected to a reaction with 2‐mercaptobenzimidazole and poly(L ‐lactic acid). The bromination of PEOD was also performed in the presence of a Br2/HBr solution at room temperature. The brominated poly(ethylene‐co‐1,7‐octadiene) (PEOD‐Br) was used as a macroinitiator for atom transfer radical polymerization. The polymerization of styrene, butyl methacrylate, and glycidyl methacrylate was performed in bulk or solution at 120°C with a PEOD‐Br/CuBr/2,2′‐dipyridyl initiator system. The thermal properties of the graft copolymers and the efficiency of the graft polymerization were investigated. These graft copolymers have potential applications as interfacial modifiers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

15.
Poly(m‐aminophenyl acetic acid) was synthesized under different conditions from the respective monomer, using ammonium persulfate as oxidizing agent in both the presence and the absence of CuCl2 in HCl(aq). Moreover, the copolymers between aniline and m‐aminophenyl acetic acid were prepared at several feed mol ratios (f1) of aniline. Copper was introduced by the Batch method in the homo‐ and copolymers of different compositions. The polymers were characterized by FTIR and UV‐vis spectroscopy, elemental analysis, thermal analysis, and electrical conductivity. The thermal stability and the content of copper increased as the content of aniline was increased in the copolymers. Moreover, the copolymers showed a high thermal stability; at 400°C a weight loss < 10% was observed. The electrical conductivity was increased with a higher content of aniline in the copolymers, achieving semiconduction values. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1484–1492, 2003  相似文献   

16.
The copolymer of pyrrole and aniline, poly(pyrrole‐co‐aniline), has been prepared by chemical oxidation of corresponding monomer mixtures with ammonium peroxysulfate. Techniques of FTIR, SEM‐EDS, and BET surface area measurement were used to characterize the structure and morphology of the copolymer. The electrochemical properties of the copolymer were investigated by cyclic voltammetry, galvanostatic charge‐discharge, and electrochemical impedance spectroscopy. The results indicated that poly(pyrrole‐co‐aniline) was about 100–300 nm in diameter and showed better electrochemical capacitive performance than polypyrrole and polyaniline. The specific capacitance of the copolymer electrode was 827 F/g at a current of 8 mA/cm2 in 1 mol/L Na2SO4 electrolyte. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

17.
Well‐defined polystyrene (PS)‐b‐poly(ethylene oxide) (PEO)‐b‐PS triblock copolymers were synthesized by atom‐transfer radical polymerization (ATRP), using C—X‐end‐group PEO as macroinitiators. The triblock copolymers were characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, and gel permeation chromatography. The experimental results showed that the polymerization was controlled/living. It was found that when the number‐average molecular weight of the macroinititors increased from 2000 to 10,000, the molecular weight distribution of the triblock copolymers decreased roughly from 1.49 to 1.07 and the rate of polymerization became much slower. The possible polymerization mechanism is discussed. According to the Cu content measured with atomic absorption spectrometry, the removal of catalysts, with CHCl3 as the solvent and kaolin as the in situ absorption agent, was effective. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2882–2888, 2000  相似文献   

18.
Poly[aniline‐coN‐(2‐hydroxyethyl) aniline] was synthesized in an aqueous hydrochloric acid medium with a determined feed ratio by chemical oxidative polymerization. This polymer was used as a functional conducting polymer intermediate because of its side‐group reactivity. To synthesize the alkyl‐substituted copolymer, the initial copolymer was reacted with NaH to obtain the N‐ and O‐anionic copolymer after the reaction with octadecyl bromide to prepare the octadecyl‐substituted polymer. The microstructure of the obtained polymers was characterized by Fourier transform infrared spectroscopy, 1H‐NMR, and X‐ray diffraction. The thermal behavior of the polymers was investigated by thermogravimetric analysis and differential scanning calorimetry. The morphology of obtained copolymers was studied by scanning electron microscopy. The cyclic voltammetry investigation showed the electroactivity of poly [aniline‐coN‐(2‐hydroxyethyl) aniline] and N and O‐alkylated poly[aniline‐coN‐(2‐hydroxyethyl) aniline]. The conductivities of the polymers were 5 × 10?5 S/cm for poly[aniline‐coN‐(2‐hydroxyethyl) aniline] and 5 ×10?7 S/cm for the octadecyl‐substituted copolymer. The conductivity measurements were performed with a four‐point probe method. The solubility of the initial copolymer in common organic solvents such as N‐methyl‐2‐pyrrolidone and dimethylformamide was greater than polyaniline. The alkylated copolymer was mainly soluble in nonpolar solvents such as n‐hexane and cyclohexane. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

19.
BACKGROUND: Poly(1‐amino‐2‐naphthol‐4‐sulfonic acid) and its copolymers with aniline are a new class of conducting polymers which can acquire intrinsic protonic doping ability, leading to the formation of highly soluble self‐doped homopolymers and copolymers. Free ? OH and ? NH2 groups in the polymer chain can combine with other functional groups that could be present in protective paints which can thus be successfully used as antistatic materials. RESULTS: This paper reports the formation of nanotubes of polyaniline on carrying out oxidative polymerization of aniline in the presence of 1‐amino‐2‐naphthol‐4‐sulfonic acid (ANSA) in p‐toluenesulfonic acid (PTSA) as an external dopant. The presence of ? SO3H groups in the ANSA comonomer allows the copolymer to acquire intrinsic protonic doping ability. The polymerization mechanism was investigated by analysing the 1H NMR, 13C NMR, Fourier transform infrared and X‐ray photoelectron spectra of the copolymers and homopolymers, which revealed the involvement of ? OH/? NH2 in the reaction mechanism. Scanning and transmission electron microscopy showed how the reaction route and the presence of a dopant can affect the morphology and size of the polymers. Static decay time measurements were also carried out on conducting copolymer films prepared by blending of 1 wt% of copolymers of ANSA and aniline with low‐density polyethylene (LDPE) which showed a static decay time of 0.1 to 0.31 s on dissipating a charge from 5000 to 500 V. CONCLUSION: Copolymers of ANSA with aniline were synthesized in different reaction media, leading to the formation of nanotubes and nanoparticles of copolymer. Blends of 1 wt% of PTSA‐ and self‐doped copolymers of ANSA and aniline with LDPE can be formulated into films with effective antistatic properties. Copyright © 2009 Society of Chemical Industry  相似文献   

20.
The chemical redox system of ceric ammonium nitrate(Ce4+) and poly(dimethylsiloxane)s (PDMS) with monohydroxy (MH), dihydroxy (DH), and diamine(DA) chain ends was used to polymerize acrylonitrile (AN) to produce monohydroxy poly(dimethylsiloxane)s‐b‐polyacrylonitrile (MH.PDMS‐b‐PAN), dihydroxy poly(dimethylsiloxane)s‐b‐polyacrylonitrile (DH.PDMS‐b‐PAN), and α, ω‐diamine poly(dimethylsiloxane)s‐b‐polyacrylonitrile (DA.PDMS‐b‐PAN) block copolymers. The concentration, reaction time, and the type of poly(dimethylsiloxane) affect the yield and the molecular weight of the copolymers. The ratio of AN/ceric salt/PDMS has remarkably affects the properties of formed copolymers. DH.PDMS‐b‐PAN copolymers were also prepared by electroinduced polymerization in the presence of catalytic amount of Ce4+ in a divided electrochemical cell where Ce3+ is readily oxidized into Ce4+ at the anode. The products were characterized by Fourier transform infrared spectroscopy, 1H‐NMR spectroscopy, DSC, and their surface properties were investigated through contact‐angle measurements. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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