3,4-乙撑二氧噻吩的合成研究

通过3,4-二溴噻吩与甲醇钠反应合成了中间体3,4-二甲氧基噻吩,再将3,4-二甲氧基噻吩与乙二醇于甲苯中反应,得到标题化合物,总收率为45%.     

3,4-乙撑二氧噻吩的合成工艺研究进展

聚3,4-乙撑二氧噻吩具有导电率高、热稳定性好、成膜性好的特点。在光伏电池、抗静电与电磁屏蔽等领域具有良好的用途。由于传统的3,4-乙撑二氧噻吩单体合成过程繁杂,导致3,4-乙撑二氧噻吩单体收率低、价格昂贵,至今未得到良好应用。本文介绍了合成3,4-乙撑二氧噻吩单体的最新研究进展,着重讨论了以价廉易得的氯乙酸乙酯为原料,经亲核取代、酯缩合、烷基化、水解与脱羧合成3,4-乙撑二氧噻吩的新"五步法"合成路线。通过对3,4-乙撑二氧噻吩新"五步法"合成路线的分析,总结了各步最优合成方法与条件,为3,4-乙撑二氧噻吩研究开发提供了借鉴。     

3,4-乙撑二氧噻吩合成及其聚合物应用进展

3,4-乙撑二氧噻吩(EDOT)是导电聚合物——聚3,4-乙撑二氧噻吩(PEDOT)的单体。目前,国内EDOT的产量和品质等方面较国外有较大差距。因此,对EDOT的合成工艺进行深入研究有着重要的社会和经济效益。总结了EDOT的主要合成方法及其聚合物在防腐蚀涂层、超级电容器、钙钛矿太阳能电池、水凝胶等领域的应用与发展。     

新方法合成3，4-乙撑二氧噻吩系列化合物

从2,3-二甲氧基-1,3-丁二烯衍生物出发,微波辐射下采用一锅法成功合成了一系列3,4-乙撑二氧噻吩类化合物.3,4-乙撑二氧噻吩类化合物的结构经13CNMR、1HNMR、IR和元素分析进行了表征.此外,本文讨论了原料的量、催化剂和溶剂对3,4-乙撑二氧噻吩(EDOT)收率的影响.     

聚(3,4-乙撑二氧噻吩)/木质素磺酸核壳粒子的制备工艺优化

以过硫酸钠为氧化剂,在木质素磺酸(LS)水溶液中通过化学氧化法聚合3,4-乙撑二氧噻吩(PEDOT),制备聚(3,4-乙撑二氧噻吩)/木质素磺酸(PEDOT/LS)水分散液。研究了木质素磺酸用量、氧化剂添加量、p H值、固含量和反应温度对产物PEDOT/LS的粒径及导电性的影响。实验得出较佳的反应条件是:木质素磺酸与EDOT单体质量比为2.0~2.5:1,氧化剂与EDOT摩尔比为1.3:1,反应体系p H值约1.5,固含量在1.8%~2.5%,反应温度10~20℃。用PEDOT/LS配制得到的涂层,表面电阻小于108??sq?1,光滑透明且附着力达到二级,满足抗静电剂的要求。     

导电聚合物单体3，4-乙烯二氧噻吩的合成

以硫代二甘酸为起始原料,经过五步反应得到产物3,4-乙烯二氧噻吩（EDOT）,过程如下：首先在浓硫酸催化条件下,硫代二甘酸与甲醇酯化生成硫代二甘酸二甲酯,产率为93．2％;产物进而与草酸二乙酯反应后得到3,4-二羟基噻吩-2,5-二甲酸二甲酯,产率为92．0％;然后经O-烷基化反应,反应中加入四丁基溴化铵作为相转移催化剂,得到3,4-乙烯二氧噻吩-2,5-二羧酸二甲酯,再经水解得到3,4-乙烯二氧噻吩-2,5-二甲酸;在DMSO为溶剂、氮气保护条件下,3,4-乙烯二氧噻吩-2,5-二甲酸在碱式碳酸铜催化作用下脱去两分子C02得到终产物EDOT。本方法中间产物及终产物的结构经由IR证实,并经过GC含量分析,总收率为34．6％。     

用聚3,4-乙撑二氧噻吩对聚丙烯腈进行导电改性的研究

采用原位化学氧化聚合方法在聚丙烯腈纤维表面生成聚3,4-乙撑二氧噻吩,制备得到纤维表面均匀覆盖聚3,4-乙撑二氧噻吩的改性导电纤维,其电导率约为1×10-3S/cm。纤维表面与导电聚合物的相互作用改善了原纤维的耐热性能,并对其力学性能没有造成伤害。     

CuY型分子筛催化合成3,4-乙撑二氧噻吩

以2,5-二羧酸-3,4-乙撑二氧噻吩为原料,首次采用CuY型分子筛作催化剂应用于3,4-乙撑二氧噻吩合成,反应温度有了明显降低,合成条件更温和,产品收率更高。通过实验探讨了催化剂、温度、溶剂等因素对反应的影响。结果表明:当采用CuY型分子筛为催化剂、二甲基亚砜为溶剂、反应温度为135℃时,收率最高。产品结构经1 H NMR、13C NMR、IR和元素分析进行了表征。     

3,4-二氧乙基噻吩及其聚合物的制备与应用进展

聚(3,4-二氧乙基噻吩)(PEDOT)是目前发现的导电态最稳定的导电高分子之一,对聚PEDOT及其单体3,4-二氧乙基噻吩(EDOT)的制备方法进行了综述,并介绍了PEDOT在抗静电、电解电容器、有机光电材料和传感器领域的研究和应用。     

4,7-二（2,3-二氢噻吩并[3,4-b][1,4]二噁英-5-基）苯并[1,2,5]噻二唑的合成及其电聚合

聚噻吩的重要衍生物聚（3,4-乙撑二氧噻吩）（PEDOT）是应用最成功的导电高分子聚合物之一。以苯并噻二唑为受体单元,设计合成了前驱体化合物4,7-二（2,3-二氢-噻吩并[3,4-b][1,4]二噁英-5-基）苯并[1,2,5]噻二唑（EDOT-BT-EDOT）,发现其具有优异的桔红色发光性能,对其进行电聚合能够获得相应聚合物材料P（EDOTBT-EDOT）。聚合物材料表现出良好的电化学活性和稳定性以及平整致密的表面形貌。     

Redox behavior and optical response of nanostructured poly(3,4-ethylenedioxythiophene) films grown in a camphorsulfonic acid based micellar solution

Poly(3,4-ethylenedioxythiophene) (PEDOT) films have been electropolymerized from an aqueous micellar solution comprising camphorsulfonic acid (CSA), lithium trifluoromethanesulfonate (LiCF₃SO₃) and EDOT. The inclusion of the dopants CS⁻ and CF₃SO₃⁻ in the polymer structure and an unusually high doping level of 0.54 have been ascertained by the X-ray photoelectron spectroscopy. Transmission electron microscopy and atomic force microscopy studies show that the micellar effect of CSA leads to a morphology wherein polymer particles link together to form elongated shapes and also endows the film with a surface roughness of 25-30 nm. These nanostructures permit a facile intercalation-deintercalation of anions in the film during redox cycling. Electrochemical impedance spectroscopy show that the charge transfer phenomenon at the PEDOT-electrolyte interface is dominant in the high frequency region and diffusion controlled ionic movement prevails in the low frequency regime. The use of these films as potential cathodes in electrochromic windows is rationalized not only on the basis of their high scalability and ease of processing but also due to their large coloration efficiency (123 cm² C⁻¹) and transmission modulation (50%) at a photopic wavelength of 550 nm. But further improvement in color-bleach kinetics and reproducibility of redox behavior is desirable to broaden their spectrum of utility.     

Effects of preparation method on thermoelectric properties of poly(aniline-co-3,4-ethylenedioxythiophene)/SWCNT composites

Composites of conducting polymer and single-walled carbon nanotubes (SWCNTs) are attracting great attentions in harvesting low-grade waste heat. Prefabricated SWCNTs film used as the working electrode was placed at the liquid interface between the inorganic phase (dilute sulfuric acid solution) and the organic phase consisting of dichloromethane (DCM), aniline (ANI), and 3,4-ethylenedioxythiophene (EDOT), together with a platinum wire (the counter electrode) and a silver chloride (AgCl/Ag) electrode (the reference electrode), to perform electrochemical polymerization of ANI and EDOT at the liquid interface. Thermoelectric (TE) composites of poly(ANI-co-EDOT) and SWCNTs were produced. Compared with composites from ultrasonic mixing and coating methods, the 10 wt% SWCNTs-composites in situ formed in electrochemical polymerization have the highest power factor (PF) of 41.56 ± 3.58 μW m⁻¹ K⁻², higher than the PF values of the composites formed by other two methods. The work indicates that the TE properties of ANI-EDOT copolymer/SWCNT (poly[ANI-co-EDOT]/SWCNT) composites prepared by electrochemical polymerization were better than those of the composites obtained by physical mixing the electrochemically synthesized poly(ANI-co-EDOT) with SWCNTs. Moreover, SWCNTs treated with sodium dodecylbenzene sulfonate (SDBS) could further improve the TE properties of the composites.     

Synthesis and electrochemical capacitance of core-shell poly (3,4-ethylenedioxythiophene)/poly (sodium 4-styrenesulfonate)-modified multiwalled carbon nanotube nanocomposites

A noncovalent method was used to functionalize multiwalled carbon nanotubes with poly (sodium 4-styrene sulfonate). And then, the core-shell poly (3,4-ethylenedioxythiophene)/functionalized multiwalled carbon nanotubes (PEDOT/PSS-CNTs) nanocomposite was successfully realized via in situ polymerization under the hydrothermal condition. In the process, PSS served for not only solubilizing and dispersing CNTs well into an aqueous solution, but also tethering EDOT monomer onto the surface of CNTs to facilitate the formation of a uniform PEDOT coating. Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) were used to characterize the resultant PEDOT/PSS-CNTs. In addition, the PEDOT/PSS-CNTs nanocomposite (50 wt.% PEDOT) had a specific capacitance (SC) of 198.2 F g⁻¹ at a current density of 0.5 A g⁻¹ and a capacitance degradation of 26.9% after 2000 cycles, much better than those of pristine PEDOT and PEDOT/CNTs (50 wt.% PEDOT). The enhanced electrochemical performance of the PEDOT/PSS-CNTs nanocomposite (50 wt.% PEDOT) should be attributed to the high uniform system of the nanocomposite, resulting in the large surface easily contacted by abundant electrolyte ions through the three-dimensional conducting matrix.     

Organic–inorganic composites consisted of poly(3,4-ethylenedioxythiophene) and Prussian Blue analogues

The organic–inorganic material consisted of poly(3,4-ethylenedioxythiophene) (pEDOT) and copper hexacyanoferrate (Cuhcf) was synthesized. The pEDOT film with Fe(CN)₆^3−/4− as counter-ions potentiodynamically polarized in aqueous CuCl₂ electrolyte brings about stable hybrid material (pEDOT/Cuhcf) performing single redox activity of Fe^II/III at a formal potential E_f = 0.61 V (vs. Ag/AgCl/0.1 M KCl) and less clearly shaped two redox coming from copper ions entrapped inside the film. XPS ex situ measurements show three different binding energies for copper (Cu 2p_3/2: 932.2, 934.8 and 936.3 eV) and two for iron (Fe 2p_3/2: 708.2 and 709.0 eV). Spectroelectrochemical measurements allowed to establish an order in the energy band gap (E_g) for the investigated hybrids pEDOT/Mehcf (Me = Fe, Co, Ni, Cu) as follows: E_{g(pEDOT/Fehcf)} = 1.40 eV < E_{g(pEDOT/Cohcf)} = 1.48 eV < E_{g(pEDOT/Nihcf)} = 1.52 eV < E_{g(pEDOT/Cuhcf)} = 1.6 eV. The hybrid materials were examined as electrodes for electrocatalytic reduction of H₂O₂. Copper centres in pEDOT/Cuhcf as well as high spin iron centres in pEDOT/Fehcf were found to be electrocatalytically active towards hydrogen peroxide reduction.     

Electrochemical characterization of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with sulfonated thiophenes

Sulfonated thiophenes, sodium 2-(3-thienyloxy)ethanesulfonate (C₆H₇S₂O₄Na) and sodium 6-(3-thienyloxy)hexanesulfonate (C₁₀H₁₅S₂O₄Na), were synthesized and used in the fabrication of ion-selective electrodes (ISEs) sensitive and selective to Ag⁺. The Ag⁺-ISEs were prepared by galvanostatic electropolymerization of 3,4-ethylenedioxythiophene (EDOT) on glassy carbon (GC) electrodes, with either C₆H₇S₂O₄⁻ or C₁₀H₁₅S₂O₄⁻ as the charge compensator (doping ion) for p-doped poly(3,4-ethylenedioxythiophene) (PEDOT). Potentiometric measurements were carried out with these sensors, GC/PEDOT(C₆H₇S₂O₄⁻) and GC/PEDOT(C₁₀H₁₅S₂O₄⁻), to study and compare their sensitivity and selectivity to silver ions. PEDOT(C₆H₇S₂O₄⁻) and PEDOT(C₁₀H₁₅S₂O₄⁻) films were also studied by using other techniques such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), electrochemical quartz crystal microbalance (EQCM) and Fourier transform infrared spectroscopy (FTIR).Results from the potentiometric measurements showed that the difference in length of the alkyl chain of the doping ions C₆H₇S₂O₄⁻ and C₁₀H₁₅S₂O₄⁻ has no significant effect on the sensitivity or selectivity of GC/PEDOT(C₆H₇S₂O₄⁻) and GC/PEDOT(C₁₀H₁₅S₂O₄⁻) sensors to Ag⁺. More differences can be seen in the cyclic voltammograms and EIS spectra of the sensors. FTIR spectra confirmed that both C₆H₇S₂O₄⁻ and C₁₀H₁₅S₂O₄⁻ act as doping ions in the electrosynthesis of PEDOT-based films and they are not irreversibly immobilized in the polymer backbone.     

导电聚合物PEDOT/PSS-MPEG的制备及性能

引言导电高分子既有导体材料的光电学特性,又有良好的力学性能和可加工性[1],这使得导电高分子材料具有广泛的应用前景。聚噻吩类有机导电材料[2]就是这类材料中的一种。聚噻吩的室温电导率     

Electrochemical Synthesis of Poly(3,4-ethylenedioxythiophene) on Steel Electrodes: Properties and Characterization

Electrodeposition of poly(3,4-ethylenedioxythiophene) by electrochemical polymerization of 3,4-ethylenedioxythiophene has been performed on steel electrodes rather than on the typically used inert electrodes (Pt, Au, graphite carbon). The polymer was generated by cyclic voltammetry, chronopotentiometry and chronoamperometry from a 10 mM monomer solution in acetonitrile with 0.1 M LiClO₄. Elemental analysis of the generated polymer indicated that the monomeric units support 0.54 positive charges balanced with CIO₄ ¹⁴⁻ counterions. Electrochemical, electrical and structural properties of the prepared material have been characterized. The good adherence of films combined with its excellent properties indicate that poly(3,4-ethylenedioxythiophene) can be a suitable material for anticorrosion applications.