Synthesis and characterization of a new soluble conducting polymer and its electrochromic device

A mixture of isomers 2,5-di(4-methyl-thiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole, 2-(4-methyl-thiophen-2-yl)-5-(3-methyl-thiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole and 2,5-di(3-methyl-thiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole (Me-SNS(NO₂)) were synthesized. Resulting monomers were polymerized chemically, producing soluble polymers in common organic solvents. The average molecular weight has been determined by gel permeation chromatography (GPC) as Mn=5.6×10³ for the chemically synthesized polymer. The monomers were also electrochemically polymerized in the presence of LiClO₄, NaClO₄ (1:1) as the supporting electrolyte in acetonitrile solvent. Resulting polymers were characterized via CV, FTIR, NMR, SEM and UV–Vis spectroscopy. Spectroelectrochemistry analysis of polymer revealed Π–Π^* transition below 300 nm, with an electronic band gap of 2.18 ev. Switching ability of the polymer was evaluated by kinetic study measuring percent transmittance (%T) at the maximum contrast point, indicating that poly(Me-SNS(NO₂)) is a suitable material for electrochromic devices.     

Development and characterization of a new conducting carbon composite electrode

A new conducting composite flexible material prepared from cellulose acetate (CA) polymer and graphite has been developed and used for the fabrication of electrodes, which were then characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Scanning electron microscopy (SEM) was used to provide information concerning the morphology of the composite electrode surface. The potential window, background currents and capacitance were evaluated by cyclic voltammetry in the pH range from 4.6 to 8.2. The voltammetry of model electroactive species demonstrates a close to reversible electrochemical behaviour, under linear diffusion control. The electroactive area of the composite electrodes increases after appropriate electrode polishing and electrochemical pre-treatment. The electrodes were used as substrate for the electropolymerisation of the phenazine dye neutral red, for future use as redox mediator in electrochemical biosensors. The composite electrodes were also successfully used for the amperometric detection of ascorbate at 0.0 V vs. SCE, and applied to the measurement of ascorbate in Vitamin C tablets; the sensor exhibits high sensitivity and a low detection limit of 7.7 μM. Perspectives for use as a versatile, mechanically flexible and robust composite electrode of easily adaptable dimensions are indicated.     

Preparation and characterization of conducting polyaniline layered magnetic nano composite polymer particles

Considering the application potentials of organic materials possessing both conducting and ferromagnetic functions in various electronic devices, an attempt was made to prepare conducting polyaniline (PANI) layered magnetic nano composite polymer particles. Two routes were used to modify magnetic Fe₃O₄ core particles. In one route, seeded emulsion polymerization of methyl methacrylate (MMA) was carried out in presence of nano‐sized Fe₃O₄ core particles. In another route, cross‐linker ethyleneglycol dimethacrylate (EGDM) was used in addition to MMA. The modified composite particles were named as Fe₃O₄/PMMA and Fe₃O₄/P(MMA‐EGDM), respectively. Finally, seeded chemical oxidative polymerization of aniline was carried out in the presence of Fe₃O₄/PMMA and Fe₃O₄/P(MMA‐EGDM) composite seed particles to obtain Fe₃O₄/PMMA/PANI and Fe₃O₄/P(MMA‐EGDM)/PANI composite polymer particles. The modification of Fe₃O₄ core particles was confirmed by electron micrographs, FTIR, UV–visible spectra, X‐ray photoelectron spectra, X‐ray diffraction pattern and thermogravimetric analyses. A comparative study showed that crosslinking of intermediate shell improved the magnetic susceptibility and electrical conductivity of PANI layered magnetic nano composite particles. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and characterization of a new conjugated polymer: Polytrifluoromethylacetylene

Polytrifluoromethylacetylene (PTFMA) was synthesized from trifluoromethylacetylene (TFMA) using a PdCl₂/DMF catalyst solution or the anionic initiator n-butyl lithium. Although PdCl₂ proved to be an effective catalyst for the polymerization of TFMA, long reaction times and poor yields made characterization of the resultant polymer difficult. The use of n-butyl lithium, on the other hand, resulted in high yields of PTFMA in relatively short reaction times. The results of thermal analysis and the effects of n- and p-type doping on the electrical conductivity of the polymer are discussed.     

Synthesis and characterization of a new organic-inorganic hybrid polyphosphazene polymer

A new organic-inorganic hybrid polyphosphazene polymer was synthesized via sequential nucleophilic substitution using allylamine and phenol. The polymer was characterized by FTIR, 1H-NMR, and 31P-NMR spectra. The thermal properties were studied by DSC and TGA. It was found that the polymer has good thermal stability. Char yields of the polymer reaches to 48.6% at 800 ℃. The high char yield makes it possible in theory for the polymer to be used as flame retardant. By cross linking, the thermal stability of the polymer could be improved further.     

Synthesis and characterization of new azobenzenesulfonic acids doped conducting polyaniline

New azobenzene sulfonic acid dopants were synthesized by diazotized coupling reaction of sulphanilic acid diazonium salt with commercially available raw materials such as phenol, m-cresol and 4-phenylphenol. The structures of the dopants are confirmed by NMR and FT-IR. Polyaniline emeraldine base was doped by these new azobenzenesulfonic acid dopants in two different solvent medium such as methanol and N-methylpyrrolidinone to produce green emeraldine salt. The doping process was confirmed by FT-IR and UV-vis spectroscopy. The effect of composition of dopant on the conductivity of the polyaniline was investigated and the results suggest that the conductivity increases with the increase in the dopant concentration and attained maxima for more than 38% in the feed. The conductivity measurements reveal that all the dopants equally effective in producing in high conductivity in the range of 0.02 S/cm and the conductivity of the doped samples are insignificant to the structural difference in the dopant. WXRD and SEM analysis indicate that the doped samples are highly amorphous and porous in nature. The thermal analysis by TGA indicate that all the doped materials were highly stable up to 300 °C for high temperature applications.     

Synthesis of a novel highly conjugated conducting polymer

The new conjugated polyacetylene derivative dehydrated poly(4-hydroxy-4-phenyl-1-butyne) [dehydrated poly(HPB)] was synthesized from poly(4-hydroxy-4-phenyl-1-butyne) [poly(HPB)], which was obtained by the polymerization of 4-hydroxy-4-phenyl-1-butyne. The resulting dehydrated poly(HPB) was soluble in common organic solvents. The dehydrated poly(HPB) was found to have extended conjugated polyene structure. The dehydrated poly(HPB) was thermally stable up to 300°C. The electrical conductivity of I₂-doped dehydrated poly(HPB) was 10⁻² S cm⁻¹. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 949–953, 1998     

Synthesis and characterization of a new benzofulvene polymer showing a thermoreversible polymerization behavior

A new polymer based on a functionalized benzofulvene moiety has been synthesized by spontaneous polymerization of the monomer in the solid state. This polymer shows a very high molar mass, high solubility in the most common organic solvents, and thermoreversible polymerization properties. An interesting application in synthesis is reported.     

Synthesis and characterization of ion‐conducting polymer systems based on EPDM blends

This work reports the preparation and characterization of new polymeric ionomers based on etylene–propylene–diene copolymer (EPDM) with a high norbornene content. The sulfonation level was determined with X‐ray photoelectron spectroscopy, and the microstructural characterization was obtained through differential scanning calorimetry and dynamic mechanical analysis. In addition, the effects of certain plasticizers and polymers on the microstructures and conducting properties of these materials were studied, with special attention paid to the latter because of the interest aroused by these materials as membranes in polymer fuel cells. On the basis of the results, some of the synthesized membranes could be used for fuel cells because of their high conductivity (≥10^?2 S/cm) and good dimensional stability (any shrinkage observed). © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1017–1026, 2001     

Synthesis and characterization of a new dyestuff polymer soluble in alkaline aqueous media

Novel dyestuff polymers were successfully obtained through oxidative polymerization technique. The synthesized Schiff base and its polymer were soluble in alkaline＇aqueous medium and they have various colors in different solutions. Also, it can be said that the synthesized compounds are suitable as coloring agent （dyestuff） for textile applications. Fluorescence properties of the compounds were determined in DMF with different concentrations （mg/L）. Poly-tris（4- aminophenyl）methanol （P-TAPM） has quite high emission and excitation intensity values. Optical and electrochemical band gaps of the polymers were lower than those of the monomers indicating the more conjugated structure of the polymers. The oxidized states of the novel dyestuff compounds were examined by cyclic voltammetry （CV） technique. The solid state conductivity measurements showed that the synthesized polymers were semiconductors when exposed to the iodine vapour their conductivities could be increased. P-TAPM had the highest undoped conductivity. Thermal characterizations of the synthesized compounds were carried out by TG-DTA and DSC methods.     

Synthesis and characterization of a multiarm star polymer

A multiarm star polymer was synthesized through the grafting of oligo polyglycol with urethane chain end units onto the core of hyperbranched polyglycerol (HPG), which was obtained through the cationic ring‐opening polymerization of glycidol. Samples were characterized with ¹³C NMR, liquid chromatography/mass spectrometry, vapor pressure osmometry, and Raman spectroscopy. The degree of branching of HPG was 0.54, and the number of arms grafting onto HPG was 4. The urethane of the arms mainly reacted with the terminal hydroxy groups of HPG. The differences between the spin–spin relaxation times indicated that the terminal segments of the star were more flexible than those of the core. Grafting polyglycol polyurethane (soft segments of polyurethane is polyglycol) onto HPG improved its dimensional stability. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2356–2364, 2004     

Synthesis and characterization of a new semi-interpenetrating polymer network hydrogel obtained by gamma radiations

A new polyacrylic acid/polyhydroxybutyrate semi-interpenetrating polymer network hydrogel, the s-IPN/PAA-PHB, was prepared by a gamma radiation-induced polymerization. Thermal behavior was studied by thermogravimetric analysis (TG) and Differential scanning calorimetry (DSC), while the s-IPNs composition, FTIR spectra, and swelling kinetics were also determined. It was found that the DSC curve showed a melting point which is attributed to polyhydroxybutyrate. The TG curves showed various stages of degradation which are in correspondence of the presence of crosslinked polyacrylic acid and confirmed the higher thermal stability of the polymer network. The s-IPN/PAA-PHB composition was 10% of PHB and 90% of PAA. Moreover, the network reached approximately 600% of swelling in water, so it behaves like a superabsorbent hydrogel.     

Synthesis,characterization and photocatalytic activity of a new type of high-efficiency polyacid composite

In order to achieve the degradation of Congo red dye in wastewater, a new type of three-dimensional porous composite catalyst PW₇Mo₃Cu₂/PANI/MnO₂ was prepared by using heteropoly acid [TBA]₄H₃[PW₇Mo₃Cu₂O₃₈(H₂O)₂] doped intermediate PANI/MnO₂. Using IR, UV, SEM, XPS and other characterization techniques, it was confirmed that the heteropoly acid [TBA]₄H₃[PW₇Mo₃Cu₂O₃₈(H₂O)₂] was successfully doped into the intermediate PANI/MnO₂ to form a three-dimensional porous structure. The results of N₂ adsorption–desorption experiment indicated that the composite catalyst belongs to the type IV (a) mesoporous structure material and has a large pore size and specific surface area. Then, the composite catalyst PW₇Mo₃Cu₂/PANI/MnO₂ was used to photocatalyze the degradation of Congo red dye. Under the best photocatalytic conditions, the decolorization rate of Congo red dye reached 93.84%. After recovering and repeating the photocatalysis experiment three times, the decolorization rate of Congo red dye was 73.18%. The experimental results proved that the novel composite catalyst has a strong ability to degrade Congo red dye and reusability, and has potential application value.

     

Synthesis and characterization of ionic conducting sulfonated polybenzimidazoles

By copolymerization of the disodium‐2,2′‐disulfonate‐4,4′‐oxydibenzoic acid (SODBA), the 4,4′‐oxybis(benzoic acid) (OBBA) with the bis 3,4‐(diaminophenyl)sulfone (BDAPS), a series of high molecular weight sulfonated polybenzimidazoles (sPBI) were prepared by varying the ratio of monomers SODBA/OBBA. Polymers with ion exchange capacity (IEC) ranging from 0 to 3.2 meqH⁺/g were obtained. The chemical structure of the sPBI was confirmed by NMR, Fourier‐transform infra‐red (FTIR). Although the sPBI display a very poor solubility in organic solvents, they are, in the ammonium salt form, soluble in polar aprotic solvents such as DMF, NMP, or DMSO. Tough and ductile membranes from solution casting method were prepared. The water uptake and the ionic conductivity were determined at 30 and 90 °C. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1732–1742, 2010     

A new soluble conducting polymer and its electrochromic devices

A new polythiophene derivative was synthesized by both chemical and electrochemical oxidative polymerization of 1‐(1‐phenylethyl)‐2,5‐di(2‐thienyl)‐1H‐pyrrole (PETPy). Of which the chemical method produces a polymer that is completely soluble in organic solvents. The structures of both the monomer and the soluble polymer were elucidated by nuclear magnetic resonance (¹H and ¹³C NMR) and Fourier transform infrared (FTIR) spectroscopy. The average molecular weight has been determined by gel permeation chromatography to be M_n = 3.29 × 10³ for the chemically synthesized polymer. Polymer of PETPy was synthesized via potentiostatic electrochemical polymerization in acetonitrile (AN)/NaClO₄/LiClO₄ (0.1 M) solvent–electrolyte couple. Characterizations of the resulting polymer were performed by cyclic voltammetry, FTIR, scanning electron microscopy, and UV–vis spectroscopy. Four‐probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the polymer films were investigated. In addition, dual‐type polymer electrochromic devices based on P(PETPy) with poly(3,4‐ethylenedioxythiophene) were constructed. Spectroelectrochemistry, electrochromic switching, and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts, and optical memories. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2215–2225, 2006     

Synthesis and characterization of a new phenanthrenequinoxaline‐based polymer for organic solar cells

Two donor–acceptor (D‐A) conjugated polymers, PQx and PphQx, composed of alkylthienyl‐substituted benzo[1,2‐b:4,5‐b']dithiophene (BDTT) as the electron donor and the new electron acceptors quinoxaline (Qx) or phenanthrenequinoxaline (phQx), were synthesized with Stille cross‐coupling reactions. The number‐averaged molecular weights (M_n) of PQx and PphQx were found to be 25.1 and 23.2 kDa, respectively, with a dispersity of 2.6. The band‐gap energies of PQx and PphQx are 1.82 and 1.75 eV, respectively. These results indicate that, because phQx units have highly planar structures, their inclusion in D‐A polymers will be a very effective method for increasing the polymers' effective conjugation lengths. The hole mobilities of PQx and PphQx were determined to be 5.0 × 10^?5 and 2.2 × 10^?4 cm² V^?1 s^?1, respectively. A polymer solar cell device prepared with PphQx as the active layer was found to exhibit a power conversion efficiency (PCE) of 5.03%; thus, the introduction of phQx units enhanced both the short circuit current density and PCE of the device. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2804–2810     

Synthesis and characterization of iron oxide/polymer composite nanoparticles with pendent functional groups

We describe in this paper an approach to synthesize superparamagnetic iron oxide nanoparticles in the presence of polymerized lactic acid. The resulted particles consisted of clusters of iron oxide monocrystals, embedded inside the polymer chains. The composite particles synthesized in situ were highly dispersible in aqueous solution with good stability. X-ray diffraction and magnetometer data all confirmed the crystalline structure and super-paramagnetic property of the particles. They exhibited narrow size distribution with hydrodynamic diameters close to 80 nm. In addition, the particles were shown to have abundant surface carboxyl groups, which can be used to conjugate various biomolecules. Such a preparation would be especially useful for developing target specific MRI contrast agents or drug delivery vehicles.