ELECTROCHEMICAL COPOLYMERIZATION OF 3-（4-FLUOROPHENYL）THIOPHENE AND 3-METHYLTHIOPHENE IN BORON TRIFLUORIDE DIETHYL ETHERATE

The copolymer poly（3-（4-fluorophenyl）thiophene-co-3-methylthiophene） was successfully prepared from mixtures of 3-（4-fluorophenyl）thiophene （FPT） and 3-methylthiophene （MET） via electrochemical oxidation in boron trifluoride diethyl etherate （BFEE） and its mixed electrolytes with acetonitrile （ACN）. The influence of monomer concentration ratios on the copolymerization was investigated by using linear sweep voltammetry and cyclic voltammetry. The structure and morphology of these copolymer films were elucidated by UV-Vis, infrared spectroscopy, elemental analysis, thermal analysis and scanning electron microscopy （SEM）, respectively. The results showed that the molar ratio of FPT and MeT units, when copolymer was electrodeposited from feed ratio of FPT：MeT = 1：2, was about 1.08：1. In addition, the introduction of ACN into BFEE has little effect on the properties of as-formed copolymers.     

Electrochemical copolymerization of 9,10-dihydrophenanthrene and 3-methylthiophene and characterization of their copolymer with tunable fluorescence properties

Electrochemical copolymerization of 9,10-dihydrophenanthrene and 3-methylthiophene was successfully achieved in boron trifluoride diethyl etherate by direct anodic oxidation of the monomer mixtures. The structure and properties of the copolymers were investigated with ultraviolet–visible, Fourier transform infrared spectroscopy, ¹H nuclear magnetic resonance, fluorescence spectra, and thermal analysis. The novel copolymers had the advantages of both poly(9,10-dihydrophenanthrene) and poly(3-methylthiophene), such as good electrochemical behavior, good mechanical properties, and high electrical conductivity. Fluorescence spectroscopy studies revealed that the copolymers had good fluorescence properties, and the emitting properties of the copolymer could be parameters by changing the feed ratio of the monomer mixtures during the electrochemical polymerization.     

Electrosyntheses of high‐quality freestanding poly(fluorene‐co‐3‐methylthiophene) films with tunable fluorescence properties

The copolymerization of 3‐methylthiophene (MeT) and fluorene (FE) was successfully achieved in boron trifluoride diethyl etherate by the direct anodic oxidation of the monomer mixtures on a platinum electrode. The optimal feed ratio together with the best suitable potential for their copolymerization was determined. The as‐formed copolymer films, which were copolymerized with a feed ratio of FE/MeT = 2:1 at a constant potential of 1.3 V (vs a saturated calomel electrode), had the advantages of both poly(3‐methylthiophene) and polyfluorene, such as good electrochemical behavior, high conductivity, excellent thermal stability, and high film quality. The structure of the copolymer was investigated with ultraviolet–visible, infrared spectroscopy, and thermal analysis. Fluorescence spectroscopy studies revealed that the dedoped copolymer film in the solid state was a good blue‐light emitter with a strong emission at 435 nm and a shoulder at 459 nm. The emitting properties of the copolymer could be tuned by parameters during the electrochemical polymerization, such as the applied potential and monomer feed ratio. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4904–4915, 2006     

3-甲基噻吩和3-氯噻吩的电化学共聚

3-甲基噻吩和3-氯噻吩首次三氟化硼乙醚溶液中实现了电化学共聚。共聚物的分子结构通过电化学分析、红外和拉曼光谱得到了证实。实验结果表明：单体投料比对共聚物的结构和电化学性质有很大的影响;共聚物比3-甲基噻吩和3-氯噻吩的均聚物具有更大的充放电电容和更可逆的氧化还原性质。     

Copolymer electrosynthesis of ethyl-3-thiophene acetate and 3-methylthiophene and characterization of the resulting copolymers by spectroscopic studies

Copolymers of ethyl-3-thiophene acetate (ETA) and 3-methylthiophene (MT) were synthesized electrochemically. Electrospray ionization mass spectra of the electrolyte containing 2×10^–3 M MT + 3×10^–2 M ETA after copolymerization showed cooligomers with different combination of ETA and MT units. Just one value of the glass transition temperature was observed by differential scanning calorimetry of the formation of homogeneous copolymers. Change of the copolymer composition led to change of thermal stability characterized by thermogravimetric analysis. The morphology of the copolymer film was studied by scanning electron microscopy, indicating a homogeneous and compact film. The electroactivity of the homopolymer/copolymer films was studied. Cyclic voltammograms of the polymer films revealed that poly(ethyl-3-thiophene acetate) possesses high electroactivity in non-aqueous solution, but its electroactivity was lost entirely after 50 cycles in 0.1 M N(Bu)₄PF₆/acetonitrile solution having 5 volume percentage of water; however, the copolymer of ETA and MT maintains its high electroactivity even in the aqueous solution. Similar results were also derived from impedance and photoelectrochemical measurements. Additionally, it was found that a bilayer of poly(3-methylthiophene) and copolymer was formed.     

Enhanced redox stability and optical contrast of electrochromic copolymers from selenophene and 3-methylthiophene

Journal of Solid State Electrochemistry - A series of poly(selenophene-co-3-methylthiophene) films were synthesized by electrochemical copolymerization of selenophene and 3-methylthiophene under...     

三氟化硼乙醚溶液中聚(二苯并呋喃)的电化学合成

在三氟化硼乙醚-硫酸混合电解质溶液中,二苯并呋喃直接阳极氧化聚合可以获得高质量聚(二苯并呋喃)膜.二苯并呋喃在纯三氟化硼乙醚中的起始氧化电位为1.30 VvsSCE,远低于单体在0.1 mol.L-1Bu4NBF4乙腈溶液中的起始氧化电位(2.14 V).硫酸的加入进一步降低了二苯并呋喃的氧化电位.在三氟化硼乙醚-硫酸混合电解质溶液中,二苯并呋喃的起始氧化电位可降低至1.0 V;同时在该体系中获得的聚(二苯并呋喃)膜具有良好的电化学性质和荧光性质.     

Electrochemical polymerization of functionalized thiophene derivatives for the immobilization of proteins

The hydroxy group of 3-(2-hydroxyethyl)thiophene was protected as methyl ether 1 and as dimethyl tert-butyl silyl ether 5 before anodic polymerization. The poly[3-(2-methoxyethyl)thiophene] 2 was prepared by electrochemical homopolymerization of 1 . Ether cleavage was carried out in the polymer film 2 and the resulting poly [3-(2-hydroxyethyl)thiophene] ( 3 ) was activated with cyanogen bromide to immobilize alcohol dehydrogenase. Silylether 5 did not undergo homopolymerization but copolymerization of 5 with 3-methylthiophene ( 4 ) was successful. After cleavage of the protecting group the resulting copolymer 7 was activated by cyanuric chloride, and chymotrypsin was immobilized. Electrocopolymerization of thiophene-3-acetic acid ( 8 ) and 3-methylthiophene ( 4 ) under various conditions produces copolymer 9 . By activation of the carboxylic groups with N,N'-dicyclohexylcarbodiimide (DCC) lactate oxidase (LOD) was bond to the surface of the electrode to form a lactate sensor.     

DOPING LEVEL INCREASE OF POLY(3-METHYLTHIOPHENE)FILM DURING ELECTROCHEMICAL POLYMERIZATION PROCESS

The Raman spectra of poly(3-methylthiophene) (PMeT) films with different thicknesses, which have beenelectrochemically deposited on a flat stainless steel electrode surface by direct oxidation of 3-methylthiophene in borontrifluoride diethyl etherate (BFEE) at a constant applied potential of 1.38 V (versus SCE), have been investigated byexcitation with a 633-nm laser beam. The spectroscopic results demonstrated that the doping level of PMeT film wasincreasing during film growth. This finding was also confirmed by electrochemical examination. Moreover, the Raman bandsassigned to radical cations and dications in doped PMeT films were found approximately at 1420 and 1400 cm~(-1),respectively. Radical cations and dications coexist on the backbone of PMeT as conductive species and their concentrationsincrease with the increase of doping level. Successive cyclic voltammetry was proved to be an effective approach toimproving the doping level of as-grown thin compact PMeT film.     

Covalent immobilization of glucose oxidase on films prepared by electrochemical copolymerization of 3-methylthiophene and thiophene-3-acetic acid for amperometric sensing of glucose: Effects of polymerization conditions on sensing properties

For the purpose of glucose sensing, enzyme electrodes were fabricated via covalent immobilization of glucose oxidase on the films of conducting polymer. The films were prepared electrochemically by the copolymerization of 3-methylthiophene and thiophene-3-acetic acid. The properties of the films were investigated by taking into account the polymerization conditions (the kind of supporting electrodes, the current, the amount of passed charge, and the monomer concentration) and the dedoping treatment. The glucose sensing performance of the enzyme electrode was found to be affected markedly by the following three factors of the conducting polymer film: surface morphology, conductivity and cohesion with support electrodes. It was suggested that the ideal conducting polymer used for the enzyme electrode should be a thin film having high conductivity and ordered nanostructure.     

Preparation and properties of a methacrylate-containing siliconized epoxy hybrid monomer and its emulsion copolymerization with styrene/butyl acrylate

The objective of the present work was the synthesis and characterization of a methacrylate-containing siliconized epoxy hybrid monomer and its emulsion copolymerization in the presence of styrene/butyl acrylate monomers. The purity and structural conformation of this monomer were ascertained from FTIR and NMR spectral studies. Thermal properties of the copolymers were investigated by using differential scanning calorimetry and thermal gravimetric analysis. The morphology of copolymers was investigated by scanning electron microscopy and then the effect of siliconized epoxy hybrid monomer concentration on the water absorption ratio was examined. The results show that the water-resistance of the terpolymer films was higher compared with the films of styrene-co-butyl acrylate copolymer.     

含有不同数量间位间链接单元的聚苯胺的金属配合物催化法合成及性能

以0~20%的1,3-二溴苯为第三单体,1,4-二溴苯为第二单体与对苯醌二亚胺用Ni(Ⅱ)催化法合成了不同比例的聚(对苯醌二亚胺-1,4-二溴苯-1,3-二溴苯)无规共聚物。通过红外光谱(FT-IR)、紫外可见吸收光谱(UV-Vis)、X射线粉末衍射(XRD)、热重分析(TG)、循环伏安(CV)、充放电等测试方法对共聚物进行了表征和性能测试,探讨了共聚物链接部位对性能的影响。紫外可见吸收光谱表明,共聚物在490nm左右均出现了最大吸收峰。与P1相比,P2、P3、P4、P5在此波长处的吸收峰,分别红移了10、19、34、24nm,其中共聚物P4红移了34nm,具有较高的共轭程度;温度达到671℃时,共聚物P2分解了40%,P1在温度达到577℃时,分解了40%;循环伏安测试表明,从P1、P2、P3至P4,共聚物的峰面积逐渐开始变大,而峰面积越大,共聚物的比电容越大;但是,共聚物P5的峰面积又开始变小;充放电测试结果表明,共聚物的放电时间从P1开始增大,直到P4,共聚物的放电时间达到最长,而从共聚物P5开始放电时间减少。     

Low potential electrosyntheses of free‐standing poly(dibenzofuran) films in mixed electrolytes of boron trifluoride diethyl etherate and trifluoroacetic acid

Free‐standing poly(dibenzofuran) (PDBF) films were synthesized electrochemically by direct anodic oxidation of dibenzofuran in mixed electrolytes of boron trifluoride diethyl etherate (BFEE) containing certain amount of trifluoroacetic acid (TFA). The oxidation potential of dibenzofuran in pure BFEE was measured to be only 1.31 V versus saturated calomel electrode (SCE). This value was much lower than that determined in acetonitrile + 0.1 mol L^?1 TBATFB (2.14 V vs. SCE). The addition of TFA to BFEE can further decrease the oxidation potential of the monomer to 1.07 V versus SCE in the mixed electrolyte of BFEE + 30% TFA. PDBF films obtained from this medium showed good electrochemical behavior, good electrochromic properties, and good thermal stability with conductivity of 10⁰ S cm^?1. FTIR and ¹H NMR spectra showed that the polymer was grown mainly via the coupling of the monomer at C₍₃₎ C₍₁₀₎ or C₍₄₎ C₍₉₎ positions (Scheme 1). As‐formed PDBF films were partly soluble in tetrahydrofuran (THF) or chloroform. Fluorescent spectral studies indicated that either soluble or PDBF in solid state was a good blue light PDBF emitter. To the best of our knowledge, this is the first report that free‐standing PDBF films can be electrodeposited. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1125–1135, 2006     

Electrochemical Behavior of Polythiophene Films: Effect of Electrolyte Concentration and the Nature of the Alkyl Substituent

The electrochemical behavior of poly(3-methylthiophene) and poly(3-octylthiophene) films in solutions of 0.05–0.5 M LiClO₄ in acetonitrile is studied using cyclic voltammetry and chronoamperometry. An analysis of data on the current relaxation following a film perturbation by a pulsed small voltage reveals the presence of two constituents of the current relaxation for either polymer, each constituent exponentially depending on the time. Effect of the electrode potential and electrolyte concentration on the current relaxation parameters are studied. Results of additional studies of poly(3-methylthiophene) films by a faradaic impedance method conform to the chronoamperometry data and permit a more reliable interpretation of them.     

Synthesis and characterization of novel ferrocenyl glycidyl ether polymer,ferrocenyl poly (epichlorohydrin) and ferrocenyl poly (glycidyl azide)

Poly (ferrocenyl glycidyl ether) was synthesized by polymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane (FcEpo) using toluene solution of methylaluminoxane as the catalyst. Copolymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane with epichlorohydrin was used for the synthesis of another ferrocenyl based poly (epichlorohydrin). Ferrocenyl based poly (glycidyl azide), GAP, was synthesized by treatment of sodium azide with this copolymer in DMF as solvent at room temperature. The synthesized ferrocenyl based polymers were characterized by FT-IR, ¹HNMR, UV–Vis, TGA, DSC and GPC analysis. The UV–Vis spectra of synthesized polymers show the absorption band of ferrocene moiety at about 450 nm. The TGA and DSC analysis show that poly (ferrocenyl glycidyl ether) has good thermal stability. The TGA analysis shows that the copolymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane with epichlorohydrin improved the thermal stability of the copolymer. The GPC analysis of poly (ferrocenyl glycidyl ether), ferrocenyl based poly (epichlorohydrin) and Ferrocenyl based poly (glycidyl azide) show the PDI between 1.14–1.17. The electrochemical behavior of synthesized polymers was investigated by cyclic voltammetry (CV) measurements. The CV curves of synthesized polymers show good electrochemical performance and there is one redox system with the single-electron reversible reaction that associated with ferrocene moiety in polymers structure. The anodic and cathodic peak currents increased with scan rate confirmed redox reactions in the system are kinetically fast diffusion-controlled reactions.     

Block copolymerization of methyl methacrylate with poly(ethylene oxide) radicals formed by high-speed stirring

A block copolymer of methyl methacrylate with poly(ethylene oxide) was synthesized by initiation with poly(ethylene oxide) radicals formed by high-speed stirring. The effects of the concentration of the monomer, the concentration of the polymer, the degree of polymerization, the rotation speed, and the solvent on the rate of copolymerization were studied. It was found that the rate of copolymerization was proportional to the concentration of the monomer and to the square root of the rate of scission of the polymer chain. The block copolymerization of methyl methacrylate monomer and styrene monomer (1 : 1 mole ratio) with poly(ethylene oxide) radicals was also carried out by the same method and it was found that the block copolymerization was a radical one.     

Synthesis of a novel phosphate‐containing highly transparent PMMA copolymer with enhanced thermal and flame retardant properties

A novel poly(methyl methacrylate) (PMMA)‐based copolymer (PMMA‐co‐BDPA) rich in aromatic rings was synthesized via radical copolymerization between a phosphorus‐containing acrylic monomer (BDPA) and methyl methacrylate (MMA). UV‐vis spectroscopy demonstrated that the copolymer had high transparency. Thermogravimetric analysis (TGA) and a differential scanning calorimeter (DSC) were used to test the thermal properties of the composites. Additionally, the PMMA‐co‐BDPA‐15 copolymer exhibited a 23% increase in the limited oxygen index (LOI) value. A cone calorimeter test indicated that the peak heat release rate (pk‐HRR) of PMMA‐co‐BDPA was reduced by 29.2% compared with that of pure PMMA, and the carbon yield of burning was obviously increased. The combined test results demonstrated that the prepared copolymer material had good transparency, thermal stability, and flame retardancy.     

Amperometric glucose-responding property of enzyme electrodes fabricated by covalent immobilization of glucose oxidase on conducting polymer films with macroporous structure

Macroporous conducting polymer films were prepared by the electrochemical copolymerization of 3-methylthiophene and thiophene-3-acetic acid on the ITO-coated glass plates bearing different sizes of polystyrene template particles, and enzyme electrodes were fabricated by covalent immobilization of glucose oxidase on the macroporous copolymer films. It was found that the doping level and conductivity of the copolymer films was significantly affected by the treatment with solvent to remove the polystyrene particles, which was considered to result in deterioration in amperometric glucose-responding property of the enzyme electrodes fabricated with the copolymer films. Three-dimensionally ordered macroporous structure on the copolymer films led to enhancement of amperometric response of the enzyme electrodes, and this effect was attributed to the geometry of the interconnected channel structure formed by the linkage of macropores. It was suggested that the amperometric response of the enzyme electrodes was determined by whether the interconnected channel structure on the copolymer films had long distance regularity and a proper size to allow the enzyme and electron-mediator molecules to penetrate into the interior pores of the copolymer film. In particular, the interconnected channel structure seemed to play an important role in the electron-transfer reaction between the mediator molecules and the surface of electrodes.     

Amphiphilic block and statistical copolymers with pendant glucose residues: Controlled synthesis by living cationic polymerization and the effect of copolymer architecture on their properties

Amphiphilic block and statistical copolymers of vinyl ethers (VEs) with pendant glucose residues were synthesized by the living cationic polymerization of isobutyl VE (IBVE) and a VE carrying 1,2:5,6‐di‐O‐isopropylidene‐D ‐glucose (IpGlcVE), followed by deprotection. The block copolymer was prepared by a two‐stage sequential block copolymerization, whereas the statistical copolymer was obtained by the copolymerization of a mixture of the two monomers. The monomer reactivity ratios estimated with the statistical copolymerization were r₁ (IBVE) = 1.65 and r₂ (IpGlcVE) = 1.15. The obtained statistical copolymers were nearly uniform with the comonomer composition along the main chain. Both the block and statistical copolymers had narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight ∼ 1.1). Gel permeation chromatography, static light scattering, and spin–lattice relaxation time measurements in a selective solvent revealed that the block copolymer formed multimolecular micelles, possibly with a hydrophobic poly(IBVE) core and a glucose‐carrying poly(VE) shell, whereas the statistical copolymer with nearly the same molecular weight and segment composition was molecularly dispersed in solution. The surface properties of the solvent‐cast films of the block and statistical copolymer were also investigated with the contact‐angle measurement. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 459–467, 2001