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161.
Sevki Can Cevher Naime Akbasoglu Unlu Ali Can Ozelcaglayan Dogukan Hazar Apaydin Yasemin Arslan Udum Levent Toppare Ali Cirpan 《Journal of polymer science. Part A, Polymer chemistry》2013,51(9):1933-1941
In this study, two new benzotriazole (BTz) and dithienothiophene (DTT) containing conjugated polymers were synthesized. After successful characterizations of the monomers by proton‐nuclear magnetic resonance (1H NMR) and carbon‐NMR (13C NMR) techniques, poly(4‐(dithieno[3, 2‐b:2′,3′‐d]thiophen‐2‐yl)‐2‐(2‐octyldodecyl)‐2H‐benzo[d][1,2,3] triazole) P1 and poly(4‐(5‐(dithieno[3,2‐b:2′,3′‐d]thiophen‐2‐yl)thiophen‐2‐yl)‐2‐(2‐octyldodecyl)‐7‐(thiophen‐2‐yl)‐2H‐benzo[d][1,2,3]triazole) P2 were synthesized via a typical Stille coupling. Electrochemical and spectroelectrochemical studies showed that both polymers can be multipurpose materials and used in electrochromic and photovoltaic applications. Reported study indicated that incorporation of DTT into the structure leads to fast switching times compared with BTz‐based polymers and competent percentage transmittance in the near‐infrared region. Multichromism is important in the context of low‐cost flexible display device technology and both polymers are ambipolar and processable as well as multichromic. Throughout the preliminary photovoltaic studies, the best performances of photovoltaic devices were found as Voc = 0.49 V, Jsc = 0.83 mA/cm2, fill factor (FF) = 34.4%, and power conversion efficiency (PCE) = 0.14% for P1 , and as Voc = 0.35 V, Jsc = 1.57 mA/cm2, FF = 38.2%, and PCE = 0.21% for P2 . © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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164.
Synthesis of two novel donor – acceptor – donor type monomers containing benzimidazole as the acceptor unit and thiophene and 3,4-ethylenedioxythiophene (EDOT) as the donor units were performed. 2-(Perfluorophenyl)-4,7-di(thiophen-2-yl)-1H-benzo[d]imidazole and 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-2-(perfluorophenyl)-1H-benzo[d]imidazole were synthesized successfully and polymerized electrochemically. The electrochemical and spectroelectrochemical studies of the polymers were studied. The effect of electron donating moieties on the optical properties of electrochemically polymerized polymers was investigated. Both polymers were p type dopable and possessed multi-chromic property. Optical studies demonstrated that the polymer based on EDOT unit (P2) resulted in lower band gap since EDOT is higher electron donating group than thiophene. 相似文献
165.
Hui‐Min Wang Sheng‐Huei Hsiao Guey‐Sheng Liou Chieh‐Hsiang Sun 《Journal of polymer science. Part A, Polymer chemistry》2010,48(21):4775-4789
A new carbazole‐derived, triphenylamine (TPA)‐containing aromatic dicarboxylic acid monomer, 4,4′‐dicarboxy‐4″‐(3,6‐di‐tert‐butylcarbazol‐9‐yl)TPA, was synthesized, and it led to a series of electroactive aromatic polyamides with main‐chain TPA and pendent 3,6‐bis(tert‐butyl)carbazole units by reacting it with various aromatic diamines via the phosphorylation polyamidation technique. The polyamides were amorphous with good solubility in many organic solvents and could be solution‐cast into flexible and strong films. They showed high glass‐transition temperatures (282–335 °C) and high thermal stability (10% weight loss temperatures >480 °C). The electroactive polymer films had well‐defined and reversible redox couples with good cycle stability in acetonitrile solutions. The polymer films also exhibited fluorescent and multielectrochromic behaviors. The anodically electrochromic polyamide films had moderate coloration efficiency (~100 cm2/C) and high optical contrast ratio of transmittance change (Δ%T) up to 47% at 813 nm and 48% at 414 nm for the green coloring. After hundreds of cyclic switches, the polymer films still retained good redox and electrochromic activity. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
166.
Naime Akbaşoğlu Abidin Balan Derya Baran Ali Cirpan Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5603-5610
Two new 2‐dodecyl benzotriazole (BTz) based donor‐acceptor‐donor (DAD) type polymers were synthesized and characterized in terms of their electrochemical and spectral properties. These DAD type polymers were synthesized electrochemically from furan or thieno[3,2‐b]thiophene (TT) end‐capped BTz monomers. Furan based and thieno[3,2‐b]thiophene based monomers showed monomer oxidations at 1.15 and 1.25 V, respectively, which eased the formation of conducting polymer films without overoxidation. Cyclic voltammetry and spectroelectrochemistry studies showed that both materials are multicolored electrochromic polymers. Results and comparison with properties of other BTz based DAD type polymers are highlighted in detail. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
167.
Xiaojing Lv Qian Bi Alexey Tameev Yujian Zhang Liang Qian Mi Ouyang Cheng Zhang 《Journal of polymer science. Part A, Polymer chemistry》2020,58(7):937-947
A new neutral green electrochromic (EC) polymer, namely poly(5,8-bis(2,3-dihydro[3,4-B][1,4]dioxin-5-yl)-2,3-dual(4-(hexadecyloxy) phenyl) quinoxaline) (PBOPEQ) was designed and synthesized. PBOPEQ-poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) film was further prepared by electrochemical polymerization on the PEDOT:PSS modified indium tin oxide (ITO) electrode. Scanning electron microscopy images and ultrasonic experiment indicate that PBOPEQ-PEDOT:PSS film shows better film-forming ability and stronger interface adhesive with ITO electrode compared to that of PBOPEQ film. It is worth mentioning that PBOPEQ-PEDOT:PSS film presents more reversible redox characteristic, better optical contrast (~40%) and coloration efficiency (~230 cm2 C−1) at 678 nm, excellent EC stability and memory property (36 hr), which should be ascribed to that the electroactive PEDOT:PSS layer facilitates the charge transfer process and enhances the ion doping/dedoping properties. EC device based on PBOPEQ-PEDOT:PSS film exhibits superior integrated performance such as reversible color change from green to transmissive, optical contrast of 41.0% and switching time less than 1 s. Accordingly, PBOPEQ-PEDOT:PSS is an excellent EC material when combined with electroactive PEDOT:PSS interface layer for achieving high performance device, which shows potential applications in displays, electronic papers, and tags. 相似文献
168.
多金属氧酸盐电致变色材料 总被引:1,自引:0,他引:1
多金属氧酸盐具有多样的结构和良好的电化学可逆性,在电致变色器件(例如军事伪装、后视镜、智能窗以及高对比度信息显示器)上有着广阔的应用前景。本文综述了多金属氧酸盐在电致变色领域的研究进展情况。概述了多金属氧酸盐的电致变色机理以及制备多金属氧酸盐电致变色薄膜的方法,主要包括:溶胶-凝胶方法、电沉积法、Langmuir-Blodgett方法、层接层自组装方法。按照多金属氧酸盐的结构类型分类,结合最新文献报道,介绍了同多酸(盐)型和杂多酸(盐)型电致变色材料性能的研究现状。最后,对其未来的发展方向进行了展望。 相似文献
169.
Both sequentially deposited double-layered and codeposited composite thin films were prepared by using two kinds of phthalocyanines. The structure and the electrochromic property of these thin films were compared with those of simple phthalocyanine films. The structures of the films were analyzed by scanning electron microscopy (SEM), X-ray diffrction (XRD) and electron spin resonance (ESR) spectra. From the viewpoint of morphology and crystallinity, codeposited thin films have the same structure as the simple one, having sharp peaks at ca. 2θ=7.0° in the XRD pattern and narrow crystal grains in SEM photographs. ESR measurements have revealed that phthalocyanine molecules disperse very well in the codeposited thin films in a molecular level in comparison with the physical mixture of phthalocyanine powders. This high dispersibility of the molecules in the codeposited thin films can play a role to improve the reversibility in the electrochromism. Thus, the reversibility of the phthalocyanine, which shows irreversible electrochromism in the simple film form, can be improved by the codeposition with another phthalocyanine with reversible electrochromism. In contrast, sequentially deposted double-layered thin film gives completely different results. The electrochromism of the double-layered film depends on the property of the simple phthalocyanine thin film which is in contact with the substrate. 相似文献
170.
Jacob Jensen Henrik F. Dam John R. Reynolds Aubrey L. Dyer Frederik C. Krebs 《Journal of Polymer Science.Polymer Physics》2012,50(8):536-545
Electrochromic devices (ECDs) were prepared on flexible substrates using spray coating and slot‐die coating methods. The electrochromic materials were the conjugated electroactive polymers, poly((2,2‐bis(2‐ethylhexyloxymethyl)‐propylene‐1,3‐dioxy)‐3,4‐thiophene‐2,5‐diyl) as a vibrantly colored active material (ECP‐Magenta) and poly(N‐octadecyl‐(propylene‐1,3‐dioxy)‐3,4‐pyrrole‐2,5‐diyl) as a minimally colored, charge balancing material (MCCP). Two electrolyte systems were compared to allow development of fully printable and laminated devices on flexible substrates. Devices of various sizes, up to 7 × 8 cm2, are demonstrated with pixelated devices containing pixel sizes of 4 × 4 mm2 or 13 × 13 mm2. The transmission contrast exhibited by the devices, when switched between the fully bleached and fully colored state, was 58% at a visible wavelength of 550 nm, and the devices exhibited switching times of <10 s. Additionally, we demonstrate the utilization of printed organic photovoltaic devices (with or without the use of a lithium‐polymer battery) to power the devices between the colored and bleached state, illustrating a self‐powered ECD. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献