Electropolymerization of o‐phenylenediamine on Pt‐electrode from aqueous acidic solution: Kinetic,mechanism, electrochemical studies and characterization of the polymer obtained

Electropolymerization of O‐phenylenediamine (o‐PD) on Pt‐electrode from a deoxygenated aqueous acid medium was carried out using cyclic voltammetry technique. The kinetic parameters were calculated by means of electrochemical data. The experimentally obtained kinetic equation was R_P,_E = k_E [monomer]^1.19 [acid]^1.23 [electrolyte]^0.87 from the value of the anodic current density using cyclic voltammetry technique. The apparent activation energy (E_a) is found to be 28.34 kJ mol^?1. The polymer films obtained have been characterized by X‐ray diffraction, elemental analysis, scanning electron microscopy, ¹H‐NMR, ¹³C‐NMR, UV‐visible, and IR spectroscopy. The mechanism of the electrochemical polymerization reaction has been discussed. TGA is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Electropolymerization of pyrrole and characterization of the obtained polymer films

Electrochemical oxidative polymerization of pyrrole on platinum electrode in acid medium was carried out. Different reaction parameters were investigated such as current density, acid concentration, monomer concentration, and temperature with duration of time. The orders of the electropolymerization reaction were found to be 1.3, 1.26, and 1.2 with respect to current density, acid concentration, and monomer concentration, respectively. The apparent activation energy was found to be 38.3 kJ mol^?1. The obtained polymer films were characterized by ¹H‐NMR, elemental analysis, thermogravimetric analysis, and cyclic voltammetry. The mechanism of the electrochemical polymerization reaction was also discussed. The surface morphology of the obtained polymer film was characterized by X‐ray diffraction and scanning electron microscopy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1783–1792, 2003     

Electropolymerization kinetics of a binary mixture of pyrrole and o‐aminobenzoic acid and characterization of the obtained polymer films

Poly (pyrrol‐co‐o‐aminobenzoic acid) has been synthesized electrochemically from an aqueous acid medium. The initial rate of electrocopolymerization reaction on platinum electrode is small and the rate law is: Rate = K₂ [D]^1.02[HCl] ^1.44[M]^2.00. The apparent activation energy (E_a) is found to be 90.11 kJ mol^?1. The polymer films obtained have been characterized by cyclic voltammetry, X‐ray diffraction, elemental analysis, thermogravimetric analysis, scanning electron microscopy, ¹H NMR, and IR‐spectroscopy. The mechanism of the electrochemical polymerization reaction has been discussed. The monomer reactivity ratios (r₁ and r₂) were calculated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Electrocopolymerization kinetics of a binary mixture of 3‐chloroaniline 2‐amino‐4‐phenylthiazole and characterization of the obtained block copolymer films

Electrocopolymerization of a binary mixture of 3‐chloroaniline and 2‐amino‐4‐phenylthiazole on platinum electrode in acid medium was carried out under different reaction conditions such as temperature, current density, hydrochloric acid, and monomer concentrations with duration time. The initial rate of the electrocopolymerization reaction on platinum electrode is small and the rate law is R_p = K₂ [D]^1.29[HCl]^0.97[M]^1.94. The apparent activation energy is found to be 38.87 kJ/mol. The obtained copolymer film is characterized by ¹H‐NMR, elemental analysis, GPC IR, UV‐visible, and cyclic voltammetry and compared with those of the two homopolymers. The mechanism of the electrocopolymerization reaction is also discussed and the monomer reactivity ratio (r₁and r₂) is calculated. The thermogravimetric analysis (TGA) is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. X‐ray and scanning electron microscopic analysis are used to investigate the surface morphology. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2076–2087, 2005     

Electropolymerization of p‐phenylenediamine on Pt‐electrode from aqueous acidic solution: Kinetics,mechanism, electrochemical studies,and characterization of the polymer obtained

Ar plasma‐induced graft polymerization of poly(ethylene glycol) (PEG) on Ar plasma pretreated poly(methyl methacrylate) (PMMA) surfaces was carried out to improve the antistatic properties. The surface composition and microstructure of the PEG‐grafted PMMA surfaces from plasma induction were characterized by attenuated total reflectance Fourier transfer infrared (ATR‐FTIR) spectroscopy, water contact angles (CA), and atomic force microscopy (AFM) measurements. The measurements revealed that the antistatic properties can be remarkably improved with the surface resistivity of PEG‐grafted PMMA surface decreasing significantly by 3–6 orders of magnitude, with the optimum condition for polymerization grafted onto the Ar plasma pretreated PMMA surface being 40 W for RF power and 3 min for glow discharge time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Electropolymerization and properties of 3,4‐ethylenedioxythiophene backbone polymer with tetrathiafulvalene as pendant

Three 3,4‐ethylenedioxythiophene (EDOT) derivatives, including an EDOT‐tetrathiafulvalene (TTF) derivative, were synthesized by Steglich esterification of carboxylic acids with hydroxymethyl EDOT (3,4‐ethylenedioxythiophene methanol). The UV spectra showed that there was no distinctive intramolecular interaction for the EDOT–TTF monomer between the EDOT and the TTF moieties in the ground state; however, the cyclic voltammetry responses implied that such intramolecular interaction occurred. Electropolymerization in excessive potential could bring in strong overoxidation effects and degradation in the polymer film. The polymers were simulated using density functional theory with Gaussian03 package and the optimized HOMO and LUMO state were figured out. The conductivity of TTF‐polymer was 6 S·cm^?1 obtained by galvano station and 4.8 × 10^?3 S·cm^?1 obtained by potentiostatic electropolymerization after doping with 7,7,8,8‐tetracyanoquinodimethane. The results indicated that this polymer was a reasonable candidate for conducting materials and it was meaningful to increase the conductive dimensions of TTF polymers by chemical doping. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

On the Relaxation Rate in the Primary Transition Region of Amorphous Polymers

Abstract

It is known that the stress relaxation behaviour of solids is largely independent of their structure. This similarity is expressed as F ≈ 0.1σ₀? where F is the maximum slope of the relaxation curve in a stress In(time)-diagram and σ₀? the initial effective stress of the experiment. This relation is found to be valid in temperature regions where no transitions occur; it is not expected to hold in the primary transition region of amorphous polymers. With reference to the theory of a damped Debye lattice, it is shown that the maximum value of F/σ₀? is ca. 0.28 in this region. It is further pointed out that Fσ₀? varies with temperature in a way reminiscent of that of the mechanical loss factor. The predictions are in agreement with experimental facts.     

Kinetic studies on the electrochemical polymerization of 3‐chloroaniline and characterization of the obtained polymer films

Electropolymerization of 3‐chloroaniline on a platinum electrode in an acid medium was carried out under different reaction conditions of temperature, current density and hydrochloric acid and monomer concentrations with duration time. The initial rate of the electropolymerization reaction was small, and the orders were 0.99, 0.96 and 1.2 with respect to current density and acid and monomer concentrations, respectively. The apparent activation energy was 41.6 kJ/mol. The rate law was R_p = k₂(Current density)^0.99[HCl]^0.96[Monomer]^1.2. The obtained polymer films were characterized by ¹H‐NMR, elemental analysis, IR spectroscopy, and cyclic voltammetry. The mechanism of the electropolymerization reaction is also discussed. Thermogravimetric analysis was used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. X‐ray and scanning electron microscopic analysis are used to investigate the surface morphology. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 941–953, 2004     

Electropolymerization and ion exchange properties of a polypyrrole film doped by para‐toluene sulfonate

Electropolymerization and ion exchange properties of the polypyrrole film doped by para‐toluene sulfonate (PPy/pTS) were investigated in aqueous solutions. The film with a column‐like surface morphology was galvanostatically synthesized at 3 mA/cm² during 1800 s. Cyclic voltammetric measurements of the PPy/pTS film in sodium para‐toluene sulfonate (NapTS), tetraethylammonium chloride ((C₂H₅)₄NCl), and NaCl aqueous solutions showed a cation exchange property, an anion exchange property, and a combination of them, respectively. Moreover, the large ions could decrease the transport of the small ions coexisting in the same solution, and the redox processes were proved to be electrochemically irreversible and ion transport‐limiting reactions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2518–2522, 2006     

Copolymers of aniline and o‐methoxyaniline: Synthesis and characterization

High‐conversion (HC) copolymers of aniline and o‐methoxyaniline (o‐anizidine) were synthesized for the first time by chemical oxidative copolymerization by using various polymerization techniques (simultaneous or consecutive introduction of comonomers into the polymerizing system). Low‐conversion (LC) copolymers have also been synthesized for comparison. The polymers obtained were characterized by using ¹H‐NMR, infrared, and electronic absorption spectroscopy; differential scanning calorimetry; and electrical conductivity measurements. Solubility characteristics and composition of different fractions of the copolymers were also determined. It was shown that, in contrast to the LC copolymers, HC copolymers reveal relatively poor solubility. Electrical conductivity of copolymers and also of o‐methoxyaniline homopolymer is lower as compared to polyaniline, which correlates with notable hypsochromic (blue) shift of the bands in electronic absorption spectra. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1822–1828, 2005     

The preparation of molecularly imprinted poly(o‐phenylenediamine) membranes for the specific O,O‐dimethyl‐α‐hydroxylphenyl phosphonate sensor and its characterization by AC impedance and cyclic voltammetry

A molecularly imprinted polymer (MIP) membrane for sensing O,O‐dimethyl‐α‐hydroxylphenyl phosphonate (DHP) has been prepared by electropolymerizing o‐phenylenediamine on the glassy carbon electrodes in the presence of DHP. Optimization studies with the aim to enhance insulating properties and response kinetics of the polymer membrane were carried out with respect to template molecular concentration, the monomers concentration, the polymer membrane thick and scan rate. Cyclic voltammetry and electrochemical impedance have been used to characterize the behavior of MIP polymer membrane. The capacitive measurements were also certified the imprinting effect of the polymer layers. The experimental results showed that DHP imprinted polymer has better recognition property for the template than that of a blank polymer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2222–2227, 2006     

Copolymers of aniline and o‐methoxyaniline: Synthesis and characterization

High‐conversion (HC) copolymers of aniline and o‐methoxyaniline (o‐anizidine) were synthesized for the first time by chemical oxidative copolymerization using various polymerization techniques (simultaneous or consecutive introduction of comonomers into the polymerizing system). Low‐conversion (LC) copolymers have also been synthesized for comparison. The polymers obtained were characterized using ¹H‐NMR, infrared, and electronic absorption spectroscopy, differential scanning calorimetry, and electrical conductivity measurements. Solubility characteristics and composition of different fractions of the copolymers were also determined. It was shown that in contrast to the LC copolymers, HC copolymers reveal relatively poor solubility. Electrical conductivity of copolymers and also of o‐methoxyaniline homopolymer is lower compared to polyaniline, which correlates with notable hypsochromic (blue) shift of the bands in electronic absorption spectra. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 75–81, 2006     

Copolymers of aniline with o‐ and m‐toluidine: synthesis and characterization

Copolymers of aniline and toluidine were synthesized by oxidative chemical polymerization using different ratios of the monomers in the feed, and characterized by a number of techniques including UV–visible, IR, Raman, ¹H NMR and EPR spectroscopies, as well as by thermogravimetric analysis and conductivity measurements. The properties of the copolymers are influenced by the amount of toluidine in the copolymer. Poly(o‐toluidine) and poly(m‐toluidine) are noticeably different in their solubility and conductivity. The copolymers show better solubilities than polyaniline but have lower conductivities. Differences in the properties of the salt and base forms of the copolymers are pointed out. Copyright © 2003 Society of Chemical Industry     

Synthesis and electrical properties of copolymers of o‐phenylenediamine with aniline, 3,4‐ethylenedioxythiophene and 2,3,5,6‐tetrafluoroaniline

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     

Electropolymerization of 2-Methoxyaniline: Kinetic Studies,Mechanism, Characterization of the Polymer and Applications as Corrosion Protection for Mild Steel in Acid Medium

Electropolymerization of 2-methoxyaniline on platinum electrode in acid medium was carried out under different reaction conditions as temperature, current density, hydrochloric acid, and monomer concentrations with reaction duration time. The initial rate of the electropolymerization reaction is small and the orders are found to be 1.18, 1.25, and 0.88 with respect to current density, HCl, and monomer concentrations, respectively. The apparent activation energy (Ea) is found to be 56.87 kJ/mol. The obtained polymer films are characterized by ¹H-NMR, elemental analysis, and IR spectroscopic studies. The mechanism of the electropolymerization reaction has also been discussed. The thermogravimetric analysis (TGA) was used to confirm the proposed structure and determination of the number of water molecules associated with each polymeric chain unit. X-ray and scanning electron microscopic analysis were used to investigate the surface morphology. The corrosion behavior of uncoated and coated mild steel electrode with poly (2-Methoxyaniline) in 1 M HCl at 25°C was investigated potentiodynamically. The various electrochemical parameters (I_corr, E_corr, and P%) were calculated from Tafel plots for uncoated and coated electrodes. The influence of some coating conditions as duration time, current density of the electropolymerization, and monomer concentrations were investigated. The data reveal that the presence of coated polymer films on the electrode surface increase the cathodic and anodic polarization compared to the uncoated sample.     

对氯乙酰氨基酚的合成工艺研究与表征

以氯乙酸和二氯亚砜为原料用传统的方法合成氯乙酰氯,进而以其为酰化试剂,以对氨基酚为原料,在氯乙烷和乙酸乙酯溶剂中通过正交实验分别确定了氯乙烷为最佳溶剂和该反应的最佳反应条件为:以氯乙烷为溶剂时, n(对氨基酚)∶n(氯乙酰氯)∶n (溶剂)=1∶2.5∶9,反应温度80 ℃,反应时间3 h,最高收率为90%.同时进行了规律性实验和强化实验证明了上述最佳反应条件.并对所合成的产物进行了熔点测定、元素分析、质谱分析、红外光谱分析以及核磁共振氢谱分析,确定所合成的化合物即是目的产物.     

Three‐dimensional dielectric characterization of polymer films

Polymer films are widely used in electronic packaging applications due to their low dielectric constant and ease of fabrication. These films often exhibit anisotropic electrical and thermomechanical properties, due to orientation of polymer chains, which need to be evaluated for performance and reliability modeling of electronic packages. This article presents a dual‐capacitor technique to measure the anisotropic dielectric permittivities of such films. Results are reported for in situ measurements for several spin‐coated polymeric films, some of which exhibit different permittivities in the in‐plane (x and y) and the through‐plane (z) directions (transversely isotropic), and free‐standing liquid crystalline Vectran films which exhibit orthotropic permittivities. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2328–2334, 2001     

Synthesis and characterization of a ferrocene‐modified,polyaniline‐like conducting polymer

A novel monomer called 1,1′‐ferrocenediacyl anilide (FcA) was synthesized from ferrocene (Fc). Copolymerization was carried out between FcA and aniline (ANI) by an electrochemical method. The novel monomer and copolymer were characterized with ¹H‐NMR, Fourier transform infrared (FTIR) spectroscopy, and ultraviolet–visible (UV–vis) spectroscopy. The hydrogen protons of the benzene ring were moved to a low field in ¹H‐NMR, and the absorption band of N?Q?N (where Q is the quinoid ring) appeared in the FTIR spectrum of the polymer. The peaks of both Fc and the π–π* electronic transition in the UV–vis spectra were redshifted. The results indicate that the copolymer mainly existed as a highly delocalized conjugated system. X‐ray diffraction analysis established further proof, and the process of electrochemical deposition was observed by scanning electron microscopy. The optimal synthesis conditions of the copolymer were determined through changes in the monomer molar ratios and the scan rate. The ideal performance of the copolymer was gained when the monomer molar ratio between FcA and ANI was 1:4 and the scan rate was 50 mV/s. Furthermore, the electrochemical performances were tested in detail by cyclic voltammetry, galvanostatic charge–discharge testing, and electrochemical impedance spectroscopy. The results show that the specific capacitance of poly(1,1′‐ferrocenediacyl anilide‐co‐aniline) increased up to 433.1 F/g at 0.5 A/g, the diffusion resistance was very small, and the durability was good enough. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43217.     

Viscoelastic properties and characterization of inorganic particulate‐filled polymer composites

To identify effects of glass bead (GB) content on the dynamic mechanical properties of filled low‐density‐polyethylene (LDPE) composites, the storage modulus, loss modulus, glass transition temperature, and mechanical damping of these composites were measured using a Du Pont dynamical mechanical analysis instrument in temperature range from ?150 to 100°C. It was found that the storage modulus increased nonlinearly with an increase of the GB volume fraction. On the basis of Eshelby's method and Mori's work, an equation describing the relationship between the relative storage modulus (E′_R) and filler volume fraction for polymeric composites was proposed, and the E′_R of LDPE/GB composites were estimated by means of this equation at temperatures of ?25, 0, and 25°C, and the calculations were compared with the experimental data, good agreement was showed between the predictions and the measured data. Furthermore, this equation was verified by the experimental from Al(OH)₃ filled EPDM composites at glassy state reported in a reference. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009