Electrochromic properties of novel strictly alternating poly(amine-amide-imide)s with electroactive triphenylamine moieties

A series of novel triphenylamine-containing aromatic poly(amine-amide-imide)s (PAAIs) were prepared by the phosphorylation polyamidation reactions from the diamine, N,N′-bis(4-aminophenyl)-N,N′-diphenyl-1,4-phenylenediamine, and various imide ring-preformed dicarboxylic acids. All the PAAIs were amorphous, had good solubility in many polar aprotic solvents, and exhibited excellent thin film forming capability with good mechanical properties. They displayed relatively high glass-transition temperatures (220-306 °C) and good thermal stability, with 10% weight-loss temperatures in excess of 522 °C in air or nitrogen and char yields at 800 °C in nitrogen higher than 66%. The solutions of polymers in NMP exhibited strong UV-vis absorption bands with a maximum around 315 nm. The hole-transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the PAAIs prepared by casting polymer solution onto an indium-tin oxide (ITO)-coated glass substrate exhibited two reversible oxidation redox couples at 0.63 and 1.01 V vs. Ag/AgCl in acetonitrile solution. All the PAAIs revealed very stable electrochromic characteristics, changing color from original pale brownish to green, and then to blue at 0.67 and 1.08 V, respectively.     

Thin Film Counterelectrodes with High Li Charge Capacity for Electrochromic Windows

Summary.  Ce-V mixed oxide films have been deposited by RF sputtering with the aim of increasing the Li charge capacity of counter electrodes in smart windows. Such mixed oxides have shown high transmittance and optical passivity in the visible region. After electrode pre-conditioning by cyclic voltammetry, a good electrochemical reversibility in LiClO₄– propylene carbonate electrolyte was observed, and large Li-charge capacity under galvanostatic charging (up to 50 mCċcm⁻²) has been measured. The electrode charge capacity decreased after prolonged insertion-deinsertion cycles, whereas the photoptic transmittance remained about constant. After 800 cycles the Li-charge capacity decreased to 40 mCċcm⁻². The Li diffusion coefficient inside the films measured by electrochemical impedance and by galvanostatic titration ranged from 10⁻¹¹ cm²ċs⁻¹ to 10⁻¹³cm²ċs⁻¹. We observed that the Li charge capacity of the film electrodes is a function of the film deposition conditions, because it increased with the vanadium oxide concentration in the target and with the oxygen content in the sputtering atmosphere. Received June 23, 2000. Accepted (revised) August 7, 2000     

Rational Design of Poly(2,7‐Carbazole) Derivatives for Photovoltaic Applications

A reliable model that can be used to estimate the electronic properties (i.e., the HOMO, LUMO, and band gap energies) of conjugated polymers would be a great tool for applications in organic electronics such as light‐emitting diodes, field‐effect transistors, and photovoltaic cells. Recently, poly(2,7‐carbazole) derivatives have shown promising results when used as an active donor layer in bulk heterojunction photovoltaic cells with power conversion efficiency exceeding 7%. By using a simple correlation between density functional theory (DFT) theoretical calculations performed on six model compounds (using the repeating unit) and experimental data from the six corresponding polymers, an accurate estimation of the HOMO energy level, the LUMO energy levels, and the band gap of several poly(2,7‐carbazole) derivatives was obtained. According to the theoretical data obtained for more than one hundred repeating units, fourteen new copolymers that can be used as p‐type materials in bulk heterojunction solar cells were selected and synthesized. Experimental data obtained from these materials were then used to refine the correlation between DFT and experimental data of poly(2,7‐carbazole) derivatives.

     

Poly(ProDOT‐Et2): A High‐Contrast,High‐Coloration Efficiency Electrochromic Polymer

The synthesis and electrochemical polymerization of 3,3‐diethyl‐3,4‐dihydro‐2H‐thieno‐[3,4‐b][1,4]dioxepine (ProDOT‐Et₂) was performed resulting in a stable electrochromic polymer capable of switching between an absorbing blue neutral state and a highly transmissive sky‐blue oxidized state in sub‐second time frames. High optical switching contrast ratios (up to 75% at λ_max) and high composite coloration efficiencies (505 cm²/C) were measured.     

GelatinnZn(CF3SO3)2 Polymer Electrolytes for Electrochromic Devices

The present work is focused on gelatin‐based electrolytes doped with a range of concentration of zinc triflate (Zn(CF₃SO₃)₂). The transparent‐thin‐film samples have been represented by the notation Gelatin_nZn(CF₃SO₃)₂, where n represents the zinc triflate salt concentration in the electrolyte membranes from 0.00 wt% to 10.93 wt% . The samples have been characterized by conductivity measurements, thermal analysis, cyclic voltammetry, X‐ray diffraction (XRD), polarized optical microscopy (POM) and scanning electron microscopy (SEM). The gelatin‐based electrolytes were also tested as ionic conductors in electrochromic devices with the glass/ITO/WO₃/gelatin‐based electrolyte/CeO₂‐TiO₂/ITO/glass configuration.     

Multi‐Sensitive Microgels Filled with Conducting Poly(3,4‐ethylenedioxythiophene) Nanorods

In this work we describe the synthesis of multi‐sensitive aqueous microgel particles with incorporated conducting poly(3,4‐ethylenedioxythiophene) (PEDOT) nanorods. We demonstrate that the loaded amount of PEDOT nanorods as well as their morphology can be varied by controlling the reaction conditions such as monomer concentration and alcohol concentration in aqueous phase. Obtained microgels can be stimulated by changes in the environment temperature as well as by the repulsion/attraction forces within polymeric network due to the reversible oxidation/reduction of the conjugated polymer. Microgels with unique properties can be operated in colloidal systems or used as building blocks for the preparation of nanostructured films.

     

Poly(terthiophene)s from copolymer precursors via solid‐state oxidative conversion

Herein, we report the synthesis of conducting poly (terthiophene)s using a side chain precursor polymer approach. Random copolymers were prepared by ring opening metathesis polymerization of two norbornylene monomers, one containing a pendant terthiophene group and the other containing a pendant acetate group. Solid‐state oxidative conversion of the terthiophene units was used to produce conductive polymers. Oxidative solid‐state conversion was successful for copolymers containing as little as 1 mol % of terthiophene comonomer. The electrical and optical properties of CPs were studied as a function of the amount of electroactive moiety, terthiophene (3T), present in the copolymer. The CPs were found to have conductivity varying between 10^?1 and 10^?4 S/cm depending on the precursor copolymer compositions. The CPs obtained from all precursors had no significant difference in their energy gaps and showed blue to orange color transitions when switching from the oxidized to the neutral states, respectively. The absorbance intensity at 426 nm for poly(3T) from the precursors fits the Beer–Lambert law corresponding to the range of initial 3T content in the precursor copolymer composition (from 1 to 100 mol %). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 756–763, 2010     

多色显示树枝状聚(3, 6-双噻吩咔唑)及其共聚物的电化学和电致变色性能

设计合成了一种新型的基于咔唑单元的树枝状3, 6-双噻吩咔唑衍生物(BTCPh),通过电化学聚合法制备出其均聚物及与3, 4-乙烯二氧噻吩(EDOT)的共聚物薄膜.利用电化学工作站-紫外可见光谱联用装置对两种聚合物的光谱电化学和电致变色(EC)性能进行表征.测试结果表明,均聚物(PBTCPh)薄膜在不同电压下可显示黄、绿、蓝、灰四种颜色;而EDOT单元的引入使共聚物P(BTCPh-EDOT)进一步增加了掺杂态,从而显示出更加丰富的五种颜色(橙、绿、棕绿、蓝、灰).此外,两种聚合物薄膜均具有良好的光学对比度和快速的响应速度,因而使其在智能窗及显示器方面展现了潜在的应用前景.     

聚(3,4-乙撑二氧噻吩)导电织物的制备、结构及其电致变色性能

本文采用原位聚合法, 以耐酸性好的涤纶为基底, 制得了聚(3,4-乙撑二氧噻吩)/涤纶复合导电织物[Poly(3,4-ethylenedioxythiophene)/conducting terylene textile, PEDOT/CTT], 分析了该导电织物的形貌、导电性能及结构, 并对其电致变色性能进行了初步测试. 实验结果表明, 所得到的PEDOT/CTT具有良好的导电性和一定的电致变色性能, 有望在全固态电致变色织物的制备中获得应用.     

Bifuntional Materials Containing Preyssler-type Polyoxometalates and Iron Phenanthroline Stabilized with Poly (Allylamine Hydrochloride) for Electrochromic Energy Storage Devices

Electrochromic supercapacitors have received extensive attention owing to their ability to combine electrochromism and energy storage properties. In this paper, a bifunctional electrode material based on Preyssler-type tungstophosphate (P₅W₃₀), polyelectrolyte poly(allylamine hydrochloride) chain (PAH) modified by the iron complex (Fe(phen)₃) was synthesized by Layer-by-Layer method (LbL). Compared with the film without PAH, the composite film displays large optical contrast (35.17 %), fast response time (2.49/0.90 s for coloring/bleaching), great coloration efficiency (94.73 cm² ⋅ C⁻¹) and high specific capacitance (10.45 mF cm⁻²). Moreover, the good cycling stability (83.66 % retention of the original optical modulation after 1500 cycles, capacity retention rate is 91.46 % after 500 cycles) is achieved. In addition, the composite film is also able to visually detect the energy storage level through reversible and rapid color changes, and further use it to assemble device. This work provides an promising candidate for electrochromic and energy storage devices.     

含功能性季铵盐三苯胺聚合物的合成与电致变色和非易失性记忆性能

通过4-(4-氨基苯氧基)吡啶与4,4'-二溴二苯醚或1,4-二溴苯的偶合反应(Buchwald-Hartwig),得到聚[(4-(吡啶-4-氧基)-p-苯氧基]三苯胺或聚[4-(吡啶-4-氧基)]三苯胺,再与3-(氯甲基)-5-[4-(三氟甲基)苯基]-1,2,4-噁二唑进行季铵化反应,得到含功能性季铵盐三苯胺聚合物:聚[N-对苯氧基-N-[4-O-[2-对三氟甲基苯基-(4-氯化吡啶盐)噁二唑]基]三苯胺(PTP3FQ)和聚[N-[4-O-[2-对三氟甲基苯基-(4-氯化吡啶盐)噁二唑]基]三苯胺(PP3FQ).用核磁氢谱和红外光谱表征了PTP3FQ和PP3FQ的结构,用热失重和循环伏安法测定了PTP3FQ和PP3FQ的热性能和电化学性能.结果表明,在不外加电解质情况下,PTP3FQ和PP3FQ利用自身的季铵盐离子表现出良好的电致变色性能;将PTP3FQ和PP3FQ制成Al/聚合物/ITO结构的记忆器件,由于噁二唑基团与三苯胺形成电荷转移络合物,使记忆器件表现出非易失性可擦写(Flash)存储特性,开关比高达10~3.     

Synthesis and Thin Film Phase Behaviour of Functional Rod‐Coil Block Copolymers Based on Poly(para‐phenylenevinylene) and Poly(lactic acid)

We report the synthesis of a series of block copolymers consisting of a rod‐like semiconducting poly(2,5‐di(2′‐ethylhexyloxy)‐1,4‐phenylenevinylene) (DEH‐PPV) block and a flexible poly(lactic acid) (PLA) block that can be selectively degraded under mild conditions. Such selectively degradable block copolymers are designed as self‐assembling templates for bulk heterojunction donor–acceptor layers in organic solar cells. A lamellar microphase‐separated domain structure was identified for block copolymers with PLA volume fractions between 29 and 79% in bulk and thin films using SAXS, TEM, and AFM. Depending on the ratio of the two blocks we find either lamellae oriented parallel or perpendicular to the substrate in thin films.

     

纳米纤维素/聚3,4-乙撑二氧噻吩复合薄膜的制备及电致变色性能

以棉浆粕为原料,采用硫酸溶胀结合超声波处理的方法制备了纳米纤维素(NC).在纳米纤维素的水分散液中加入3,4-乙撑二氧噻吩单体,以过硫酸铵为氧化剂,采用原位化学氧化法制得了纳米纤维素/聚3,4-乙撑二氧噻吩(NC/PEDOT)纳米复合物.对NC和NC/PEDOT复合物进行扫描电镜、透射电镜和红外光谱分析.将纳米复合物的水分散液滴涂在氧化铟锡(ITO)玻璃表面形成复合薄膜,考察不同纳米纤维素含量对NC/PEDOT复合薄膜电致变色性能的影响.结果表明,NC呈棒状,平均直径为20 nm,长度为100~300nm;NC/PEDOT复合物中PEDOT均匀包覆在NC表面形成核壳结构,平均直径为30 nm;复合薄膜中当NC含量为60%时,其电致变色性能最好,具有最高的对比度(24.4%),最短的响应时间(1 s),最高的着色效率(51.8 cm~2/C).     

聚噻吩的合成方法

自从1977年白川英树等发现聚乙炔这种导电聚合物以来,打破了高分子材料长期以来被认为是绝缘体的观点。随后聚苯胺、聚吡咯、聚噻吩等的出现使导电聚合物的种类不断出新,其用途也扩展到如导电材料、电极材料、催化材料以及太阳能电池等应用中,且已有部分产品实现了商品化。其中,聚噻吩因其良好的稳定性、易于制备、掺杂后具有良好的光电化学性能等特点而受到广泛关注。本文总结了几种合成聚噻吩及其衍生物的常见方法,包括化学氧化聚合法、电化学聚合法、金属催化偶联法、光致合成法、光电化学沉积法,以及近年来新发现的固相聚合法和酸催化聚合法,并简要介绍了各自的合成机理及优缺点。     

Electrochromic enhancement of poly(3,4‐ethylenedioxythiophene) films functionalized with hydroxymethyl and ethylene oxide

2‐((2,3‐Dihydrothieno[3,4‐b]dioxin‐2‐yl)methoxy)methyl oxirane (EDOT‐MO) was successfully synthesized by the reaction of epichlorohydrin with hydroxymethylated‐3,4‐ethylenedioxylthiophene (EDOT‐MeOH), which was synthesized via a simple four‐step sequence. Poly(hydroxymethylated‐3,4‐ethylenedioxylthiophene) (PEDOT‐MeOH) and poly(2‐((2,3‐dihydrothieno[3,4‐b]dioxin‐2‐yl)methoxy)methyl oxirane) (PEDOT‐MO) were electrosynthesized through electropolymerization of EDOT‐MeOH and EDOT‐MO, respectively. Structural, electrochemical, optical, and thermal properties of as‐formed polymers were investigated by FTIR, cyclic voltammetry, UV–vis, and thermogravimetry. Spectroelectrochemistry studies demonstrated that PEDOT‐MeOH and PEDOT‐MO could be reversibly oxidized and reduced accompany with obvious color changes. Further kinetic studies demonstrated that the introduction of hydroxymethyl or ethylene oxide group significantly improved electrochromic properties of 3,4‐ethylenedioxythiophene (PEDOT) and resulted in high contrast ratios (57.3% at 585 nm) and coloration efficiencies (338.5 cm² C^?1), low switching voltages, and fast response time. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1989–1999     

Thermally Stabilized Blue Luminescent Poly(p‐phenylene)s Covered with Polyhedral Oligomeric Silsesquioxanes

A novel series of poly(p‐phenylene)s (PPPs) with polyhedral oligomeric silsesquioxanes (POSSs) on their side chains was prepared. The obtained POSS‐modified PPPs are as follows: 25POSS‐PPP ( 2b , containing 25 mol‐% of POSS units in all side chains), 50POSS‐PPP ( 2c , containing 50 mol‐% of POSS units in all side chains), 100POSS‐PPP ( 2d , containing 100 mol‐% of POSS units in all side chains), and 0POSS‐PPP ( 2a , as a blank polymer). Films polymer 2d showed the same absorption and photoluminescence (PL) spectra as those in CHCl₃ solution, indicating that bulky POSS units strongly suppressed intermolecular aggregation of the PPP backbone. Polymer 2d showed the same PL spectra even after thermal annealing at 150 °C for 6 h. This enhancement of PL stability is due to the significant effect of the bulky POSS units.

     

Poly[methyl(phenyl)silanediyl] modified with dansyl fluorophore: Synthesis and photophysics

The syntheses and photophysical properties of novel luminescent polysilanes modified with dansyl fluorophores on various spacer (PMPSi‐n‐DNS) are reported. The modified polysilanes were prepared by condensation reaction of dansyl amines, such as 5‐(dimethylamino)naphthalene‐1‐sulfonohydrazide or N‐(ω‐aminoalkyl)‐5‐(dimethylamino)naphthalene‐1‐sulfonamides with formylated poly[methyl(phenyl)silanediyl], yielding Schiff bases. The aldehyde groups were incorporated into the parent polymer by a one‐step reaction with dichloromethyl methyl ether in the presence of Lewis acid. Influence of the alkyl chain length (n) on the photophysical properties was investigated using absorption, steady‐state, and time‐resolved photoluminescence (PL) spectroscopy. The excitation energy transfer from the polysilane backbone to dansyl fluorophore was proved. PL decay dynamics revealed the existence of more than one excited species. In solution, the decay curves of PMPSi‐DNS (no spacer) were double exponential, whereas for PMPSi‐n‐DNS (with spacer), and, in thin films, the decays were three‐exponential. Polymer light‐emitting devices (LEDs) were prepared from the blends of modified polysilane with electroluminescent polymer poly[2,5‐dimethoxy‐1,4‐phenylene‐1,2‐ethenylene‐2‐methoxy‐5‐(2‐ethylhexyloxy)‐(1,4‐phenylene‐1,2‐ethenylene)] (M3EH‐PPV). Compared with LED made of neat electroluminescent polymer, a significant performance improvement of blend LEDs was demonstrated. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Conductivity of Poly(pyrrole)‐Poly(styrene sulfonate) Core–Shell Nanoparticles

The dielectric properties of poly(styrene) nanoparticles decorated at their surfaces with poly(styrene sulfonate) [PSS] brushes and subsequently loaded with polypyrrole (PPy) were studied. These film‐forming materials which may serve as hole‐injection layers in organic light‐emitting diodes, exhibit a core–shell‐type morphology with a core of electrically insulating poly(styrene) and a shell consisting of a corona of PSS chains which form the matrix in which the electrically conducting complex of PPy and PSS is embedded. This conducting complex exists in form of domains of nanoscale dimensions. Thin compressed pellets of these nanoparticles were studied using mainly impedance spectroscopy. Measurements were carried out in the temperature range between 123 and 453 K and frequency range from 10^?1 to 10⁶ Hz. While earlier studies were centered around the effect of polypyrrole volume fraction on the conductivity films and pellets composed of these nanoparticles, the present study reveals in which way the conductivity can be modified by exchange of the mobile inorganic counter ions of PSS. Besides the free‐acid form (H⁺), the Li⁺‐, Na⁺‐ and Cs⁺‐salts of PSS were investigated. The PPy volume fraction was the same for all PPy/PSS core–shell nanoparticles. The distance for phonon‐assisted hopping between next‐neighbor polypyrrolium chains is influenced by the presence of these inorganic cations. For all samples containing PPy, a transition from insulating to conducting behavior in the range of 300‐350 K was found. Using the fluctuation‐induced tunneling model, the average tunneling distance, as well as the potential energy barrier separating neighboring conducting grains was estimated. Finally, a detailed analysis of the dielectric spectra suggests the localization length of the charge carriers to be about 0.33 nm.