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1.
Samed Atak Merve İçli‐Özkut Ahmet M. Önal Atilla Cihaner 《Journal of polymer science. Part A, Polymer chemistry》2011,49(20):4398-4405
Optical and electrochemical properties of regiosymmetric and soluble alkylenedioxyselenophene‐based electrochromic polymers, namely poly(3,3‐dibutyl‐3,4‐dihydro‐2H‐selenopheno[3,4‐b][1,4]dioxephine) (PProDOS‐C4), poly(3,3‐dihexyl‐3,4‐dihydro‐2H‐selenopheno[3,4‐b][1,4]dioxephine) (PProDOS‐C6), and poly(3,3‐didecyl‐3,4‐dihydro‐2H‐selenopheno[3,4‐b][1,4]dioxephine) (PProDOS‐C10), are highlighted. It is noted that these unique polymers have low bandgaps (1.57–1.65 eV), and they are exceptionally stable under ambient atmospheric conditions. Polymer films retained 82–97% of their electroactivity after 5000 cycles. The percent transmittance of PProDOS‐Cn (n = 4, 6, 10) films found to be between 55 and 59%. Furthermore, these novel soluble PProDOS‐Cn polymers showed electrochromic behavior: a color change form pure blue to highly transparent state in a low switching time (1.0 s) during oxidation with high coloration efficiencies (328–864 cm2 C?1) when compared to their thiophene analogues. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
2.
《中国科学:化学(英文版)》2017,(1)
A couple of novel electrochromic materials poly(2,3,4,5-tetrakis(2,3-hydrothieno[3,4-b]dixin-5-yl)-1-methyl-1H-pyrrole)(P(t-EDOT-mPy))and poly(5,5',5",5'"-(thiophene-2,3,4,5-tetrayl)tetrakis(2,3-dihydrothieno[3,4-b][1,4]dioxine))(P(t-EDOTTh))are electrodeposited via multi-position polymerization of their tetra-EDOT substituted monomers t-EDOT-mPy and t-EDOT-Th,respectively.Compared with the linear 2D structured poly(thiophene)(E_g=2.2 eV)and poly(2,5-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)thiophene)(E_g=1.7eV),P(t-EDOT-Th)(E_g=1.62eV)has the lowest band gap.Hence,we speculate that the band gaps of the two polymers,having 3D structures,are decreased in contrast to non-substituted polymers or bi-EDOT substituted polymers,thiophene and 1-methyl-1H-pyrrole.The results indicated that P(t-EDOT-Th)thin films are more stable and show higher transmittance amid two polymers,which may find their utilization in organic optoelectronics. 相似文献
3.
Joo Bin Lee Kyung Hwan Kim Chang Seop Hong Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2012,50(14):2809-2818
New diketopyrrolopyrrole (DPP)‐containing amorphous conjugated polymers, such as poly(3‐(5‐((9,10‐bis((4‐hexylphenyl)ethynyl)‐6‐(prop‐1‐ynyl)anthracen‐2‐yl)ethynyl) thiophen‐2‐yl)‐5‐(2‐hexyldecyl)‐2‐(2‐octyldodecyl)‐6‐(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione) ( 4 ), and poly(3‐(5‐((2,6‐bis((4‐hexylphenyl)ethynyl)‐10‐(prop‐1‐ynyl)anthracen‐9‐yl)ethynyl)thiophen‐2‐yl)‐2,5‐bis(2‐octyldodecyl)‐6‐(thio phen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione) ( 7 ), were successfully synthesized via Sonogashira coupling reactions under microwave conditions. Copolymer 7 , incorporating a DPP moiety at the 9,10‐position of the anthracene ring through a triple bond, showed a much lower bandgap energy (Eg = 1.81 eV) than copolymer 4 (Eg = 2.13 eV). Tuning of the molecular frontier orbital energies was achieved by only changing the anchoring position of dithiophenyl‐DPP from the 2,6‐ to the 9,10‐position in the anthracene ring. Because of the donor–acceptor (D–A) interaction and the two‐dimensional planar structure of the X‐shaped donor monomer, the resulting polymers showed good interchain π?π stacking in the thin‐film state, despite being amorphous polymers. When the newly synthesized polymer 7 was used as a semiconductor material in an organic thin‐film transistor, the best mobility of up to 0.12 cm2 V?1 s?1 (Ion/off = ~ 4.4 × 106) was observed, which is one of the highest values recorded for amorphous polymer films reported to date. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
4.
Da Seul Yang Kyung Hwan Kim Min Ju Cho Jung‐Il Jin Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2013,51(6):1457-1467
New diketopyrrolopyrrole (DPP)‐containing conjugated polymers such as poly(2,5‐bis(2‐octyldodecyl)‐3‐(5‐(pyren‐1‐yl)thiophen‐2‐yl)‐6‐(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione) (P(DTDPP‐alt‐(1,6)PY)) and poly(2,5‐bis(2‐octyldodecyl)‐3‐(5‐(pyren‐2‐yl)thiophen‐2‐yl)‐6‐(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione) (P(DTDPP‐alt‐(2,7)PY)) were successfully synthesized via Suzuki coupling reactions under Pd(0)‐catalyzed conditions. P(DTDPP‐alt‐(2,7)PY), incorporating 2,5‐bis(2‐octyldodecyl)‐3,6‐di(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,4(2H,5H)‐dione (DTDPP) at the 2,7‐position of a pyrene ring showed a lower band‐gap energy (E. = 1.65 eV) than the 1,6‐substituted analog, P(DTDPP‐alt‐(1,6)PY) (E = 1.71 eV). The energies of the molecular frontier orbitals of the substituted polymers were successfully tuned by changing the anchoring position of DTDPP from the 1,6‐ to the 2,7‐position of the pyrene ring. An organic thin‐film transistor fabricated using the newly synthesized P(DTDPP‐alt‐(2,7)PY), as a semiconductor material exhibited a maximum mobility of up to 0.23 cm2 V?1 s?1 (Ion/off ~ 106), which was much larger than that obtained using P(DTDPP‐alt‐(1,6)PY). This distinction is attributed to morphological differences in the solid state arising from differences between the geometrical configurations of DTDPP and the pyrene ring. In addition, the organic phototransistor devices made of P(DTDPP‐alt‐(2,7)PY) showed interesting photoinduced enhancement of drain current when irradiating the excitation light whose intensity is very small. Based on the photoinduced effect on IDS, photocontrolled memory could be realized under the variation of gate voltages. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
5.
Věra Cimrová Ivan Kmínek Petra Pavlačková Drahomír Výprachtický 《Journal of polymer science. Part A, Polymer chemistry》2011,49(15):3426-3436
Two new low‐bandgap alternating copolymers (CEHTF and CEHTP) consisting of 4,6‐bis(3′‐(2‐ethylhexyl)thien‐2′‐yl)thieno[3,4‐c][1,2,5] thiadiazole and 9,9‐bis(2‐ethylhexyl)fluorene or 2,5‐bis(isopentyloxy)benzene were synthesized by Suzuki coupling reaction of corresponding comonomers. Their optical, electrochemical, and photovoltaic (PV) properties were studied and are reported. Both the copolymers exhibited long‐wavelength absorption covering the whole visible spectral region, which is in CEHTP thin films extended up to near infrared region, ambipolar redox properties, and electrochromism. High‐electron affinities and low‐optical bandgap values, 1.37 and 1.15 eV, were determined for CEHTF and CEHTP, respectively. PV devices with bulk heterojunction made of blends of copolymers and fullerene derivative [6,6]‐phenyl‐C61‐butyric acid methyl ester ([60]PCBM) were prepared and characterized. Effects of intramolecular charge transfer strength and side‐chain nature and length on photophysical properties are discussed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
6.
Mukhamed L. Keshtov Sergei A. Kuklin Igor O. Konstantinov Ilya E. Ostapov Dmitrii Y. Godovsky Elena E. Makhaeva Zhiyuan Xie Ganesh D. Sharma 《Journal of polymer science. Part A, Polymer chemistry》2019,57(13):1478-1485
A series of novel donor–acceptor (D–A) random conjugated terpolymers P2‐P4 along with the homopolymers P1 (BDT‐DPP) and P5 (BDT‐BTDQ) were designed and synthesized by copolymerizing a benzo[1,2‐b:4,5‐b]dithiophene (BDT) donor with an electron‐deficient diketopyrrolo[3,4‐c]pyrrole (DPP) unit and a benzothiadiazolo[3,4‐e]quinoxaline (BTDQ) moieties of different electron‐withdrawing strengths, and the resultant terpolymers showed broad absorption profile ranging from 300 to 1200 nm. The HOMO levels of the polymers were adjusted from ?5.23 to ?5.11 eV, and the optical bandgaps were controlled from 1.32 to 1.13 eV by changing the molar ratio of DPP and BTDQ acceptors. These terpolymers were used as a donor along with PC71BM as an acceptor for the creation of polymer solar cells, and the performance was optimized via variable the donor to acceptor ratio and solvent vapor annealing. The polymer solar cells made from the random terpolymer P3 showed the highest overall power conversion efficiency of (9.27%), which is higher than that for the corresponding homo‐polymers counterparts, that is, P1 (7.27%) and P5 (7.68%). The results demonstrate that the designing of random D‐A1‐D‐A2 terpolymers may be the best approach for efficient polymer solar cells. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1478–1485 相似文献
7.
W. S. Schlindwein Y. Gofer H. Sarker T. O. Poehler P. C. Searson 《Journal of Electroanalytical Chemistry》1999,460(1-2)
Electronically conducting polymers based on polythiophene and polyparaphenylene exhibit generally, both n-doping and p-doping. In most cases, however, the n-doping process is associated usually with poor reversibility and stability. One approach to improve the doping behavior is to modify the structure of the monomer repeat unit at the molecular level. In this paper we report on the electrochemical properties of the polymer series: pTHP, pTFP (1,4-bis(2-thienyl)-2-fluorobenzene), pTF2P (1,4-bis(2-thienyl)-2,5-difluorobenzene), and pTF4P (1,4-bis(2-thienyl)-2,3,5,6-tetrafluorobenzene) in tetramethylene sulfone (sulfolane) TBABF4 based electrolytes. 相似文献
8.
John A. Mikroyannidis Vasilis P. Barberis Věra Cimrová 《Journal of polymer science. Part A, Polymer chemistry》2007,45(6):1016-1027
A novel conjugated poly[(fluorene‐2,7‐vinylene)‐alt‐(1,4‐phenylenevinylene)] derivative 2 with quaternizable tertiary amino groups was synthesized by Heck coupling of a substituted 2,7‐dibromofluorene and 1,4‐dialkoxy‐2,5‐divinylbenzene. The corresponding quaternary ammonium cationic polyelectrolyte 3 was obtained by the treatment of 2 with bromoethane. Both polymers were soluble in common organic solvents, like tetrahydrofuran, chloroform, and dichloromethane. Polymer 3 showed a limited solubility in alcohols and was insoluble in water. Photophysical and electrochemical properties of the resulting polymers were fully investigated. An intensive green photoluminescence (PL) with maxima at 550 and 545 nm was observed from thin films of 2 and 3 polymers, respectively, red‐shifted compared with the PL emission spectra measured in the solution. The electrochemical band gaps were 2.38–2.45 eV. Single‐layer and double‐layer (with poly[3,4‐(ethylenedioxy)thiophene]/poly (styrenesulfonate) (PEDOT:PSS)) light‐emitting devices (LEDs) with ITO and Al electrodes were prepared and studied. They emitted a green light and their electroluminescence (EL) spectra were similar to those of PL thin films. The external EL efficiency was determined to be 0.43 and 0.32% for ITO/PEDOT:PSS/ 2 /Al and ITO/PEDOT:PSS/ 3 /Al LEDs, respectively. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1016–1027, 2007 相似文献
9.
[1,2,5]thiadiazolo[3,4‐g]quinoxaline acceptor‐based donor–acceptor–donor‐type polymers: Effect of strength and size of donors on the band gap
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Gurcan Gokce Baris Karabay Atilla Cihaner Merve Icli Ozkut 《Journal of polymer science. Part A, Polymer chemistry》2017,55(20):3483-3493
Electrochromic polymers based on [1,2,5]thiadiazolo[3,4‐g]quinoxaline acceptor and thiophene, 3,4‐ethylenedioxythiophene and 3,3‐didecyl‐3,4‐proylenedioxythiophene donors, namely poly(6,7‐diphenyl‐4,9‐di(thiophen‐2‐yl)‐[1,2,5]thiadiazolo[3,4‐g]quinoxaline) ( P1 ), poly(4‐(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)‐9‐(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐7‐yl)‐6,7‐diphenyl‐[1,2,5]thiadiazolo[3,4‐g]quinoxaline) ( P2 ), and poly(4‐(3,3‐didecyl‐3,4‐dihydro‐2H‐thieno[3,4‐b][1,4]dioxepin‐6‐yl)‐9‐(3,3‐didecyl‐3,4‐dihydro‐2H‐thieno[3,4‐b][1,4]dioxepin‐8‐yl)‐6,7‐diphenyl‐[1,2,5]thiadiazolo[3,4‐g]quinoxaline) ( P3 ), respectively, were electrochemically and/or chemically synthesized and characterized. Electrochemical and optical properties of the polymers were then investigated. The results, which were obtained electrochemically and optically, indicate that the polymers bearing the same acceptor and different donor units have a band gap range of 0.59–1.24 eV depending on the strength and size of the donor units and band gap determination method. A significant finding in this study was the phenomenon that when the acceptor is physically huge, the general rule that a weak donor would have a high band gap whereas a strong donor would have low band gap can be broken due to the torsional angles/steric hindrances involved with physically large donor molecules. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3483–3493 相似文献
10.
A series of π‐conjugated polymers and copolymers containing 1,4‐dioxo‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole (also known as 2,5‐dihydro‐3,6‐diphenylpyrrolo[3,4‐c]pyrrole‐1,4‐dione) (DPP) and 1,4‐phenylene units in the main chain is described. The polymers are synthesised using the palladium‐catalysed aryl‐aryl coupling reaction (Suzuki coupling) of 2,5‐dihexylbenzene‐1,4‐diboronic acid with 1,4‐dioxo‐2,5‐dihexyl‐3,6‐di(4‐bromophenyl)pyrrolo[3,4‐c]pyrrole and 1,4‐dibromo‐2,5‐dihexylbenzene in different molar ratios. Soluble hairy rod‐type polymers with molecular weights up to 21 000 are obtained. Polymer solutions in common organic solvents such as chloroform or xylene are of orange colour (λmax = 488 nm) and show strong photoluminescence (λmax = 544 nm). The photochemical stability is found to be higher than for corresponding saturated polymers containing isolated DPP units in the main chain. Good solubility and processability into thin films render the compounds suitable for electronic applications. 相似文献
11.
Two novel diketopyrrolopyrrole-based alternating copolymers, poly(2,7-(9,9-diethyl)-fluorenylvinylene-alt-2,5-bis(4′-octyloxyphe- nylmethyl)-3,6-bis(4-vinylenephenyl)pyrrolo[3,4-c]pyrrole-1,4-dione) (P1) and poly(1,4-(2,5-dioctyl- oxy)-phenylenevinylene-alt-2,5-bis(4′-octyloxyphenylmethyl)-3,6-bis(4-vinylenephenyl)pyrrolo[3,4-c]pyrrole-1,4-dione) (P2) were synthesized through Wittig polycondensation in good yields. P1 and P2 were characterized by NMR, FT-IR, UV-Vis, photoluminescence (PL) and electroluminescence (EL). EL devices with ITO/PEDOT/polymer/CsF/Al exhibited red-emitting light with the maximum EL wavelength at 620 nm and 682 nm. The results show that PL quantum yield of the polymers in thin film can be improved through N-alkylation of diketopyrrolopyrrole (DPP) with bulky substituent. EL performance of P2 was better than P1, which might be due to 1,4-dioctyloxybenzene of P2 enhancing the hole-transporting to make more charge balance. EL devices of P1 and P2 possessed low turn on voltage (2.4 V and 2.1 V, respectively), which was an advantage for PLED. 相似文献
12.
Wei Yang Jinsheng Zhao Chuansheng Cui Ying Kong Xianxi Zhang Peng Li 《Journal of Solid State Electrochemistry》2012,16(12):3805-3815
1,4-Bis(2-(3,4-ethylenedioxy)thienyl)benzene, prepared by Stille cross-coupling reaction was successfully electrochemically polymerized to give polymer 1,4-bis(2-(3,4-ethylenedioxy)thienyl)benzene (PEBE). Characterizations of the resulting polymer PEBE were performed by cyclic voltammetry (CV), UV–vis, Fourier transform infrared spectroscopy and scanning electron microscopy. Moreover, the spectroelectrochemical and electrochromic properties of the polymer film were investigated. The resulting polymer film has distinct electrochromic properties and shows three different colors (deep red, gray, and light blue) under various potentials. At the dedoped state of the polymer, the π–π* transition absorption peak is located at 510?nm and the optical band gap (E g) was calculated as 1.92?eV. The PEBE film shows a maximum optical contrast (ΔT%) of 31.0?% at 500?nm with a response time of 0.85?s. The coloration efficiency of PEBE film was calculated to be 182.2?cm2C?1. An electrochromic device (ECD) based on PEBE and poly(3,4-ethylenedioxythiophene) was also constructed and characterized. The response time was measured as 0.4?s, and the coloration efficiency of the device was calculated to be 225.4?cm2C?1. Furthermore, this ECD exhibited satisfactory optical memories and redox stability. 相似文献
13.
Derong Cao Qilin Liu Wenjing Zeng Shaohu Han Junbiao Peng Shouping Liu 《Journal of polymer science. Part A, Polymer chemistry》2006,44(8):2395-2405
Two novel alternating copolymers, poly{9,9‐dihexylfluorene‐2,7‐diyl‐alt‐2,5‐dioctyl‐3,6‐bis(4‐phenyl)pyrrolo[3,4‐c] pyrrole‐1,4‐dione} ( P1 ) and poly{9,9‐dihexylfluorene‐2,7‐diyl‐alt‐2,5‐dioctyl‐3,6‐bis(3‐phenyl)pyrrolo[3,4‐c] pyrrole‐1,4‐dione} ( P2 ), derived from 9,9‐dihexylfluorene and diketopyrrolopyrrole (DPP), have been successfully synthesized through palladium‐catalyzed Suzuki polycondensation in good yields. P1 and P2 possess moderate molecular weights and polydispersities, well‐defined structures, and excellent thermal properties with an onset decomposition temperature around 400 °C. Both P1 and P2 in thin films exhibit red photoluminescence from DPP species exclusively, with peaks at 609 and 616 nm, respectively. Cyclic voltammetry studies show that P1 and P2 have low‐lying lowest unoccupied molecular orbital energy levels at ?3.65 eV and reversible reduction processes, so these polymers may constitute another kind of red‐emitting polymer with high electron affinity. Preliminary electroluminescent results of devices with an indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer/Ba/Al configuration reveal that P1 may be a promising candidate for red emitters with a maximum brightness of 153 cd/m2 and a maximum external quantum efficiency of 0.13%, whereas the performance of P2 is relatively poor. These differences might originate from different conjugation lengths in their main chain. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2395–2405, 2006 相似文献
14.
Chin‐Ping Yang Feng‐Zhi Hsiao 《Journal of polymer science. Part A, Polymer chemistry》2004,42(9):2272-2284
A novel fluorinated diamine monomer, 1,4‐bis(4‐amino‐2‐trifluoromethylphenoxy)‐2,5‐di‐tert‐butylbenzene ( 2 ), was prepared through the nucleophilic substitution reaction of 2‐chloro‐5‐nitrobenzotrifluoride and 2,5‐di‐tert‐butylhydroquinone in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C. Fluorinated polyimides ( 5a – 5f ) were synthesized from diamine 2 and various aromatic dianhydrides ( 3a – 3f ) via thermal or chemical imidization. These polymers had inherent viscosities of 0.77–1.01 dL/g. The 5 series polyimides were soluble in N‐methyl‐2‐pyrrolidone, N,N‐dimethylacetamide, and N,N‐dimethylformamide and were even soluble in dioxane, tetrahydrofuran, and dichloromethane. 5 (C) showed cutoff wavelengths between 363 and 404 nm and yellowness index (b*) values of 6.5–40.2. The polyimide films had tensile strengths of 93–114 MPa, elongations to break of 9–12%, and initial moduli of 1.7–2.1 GPa. The glass‐transition temperatures were 255–288 °C. The temperatures of 10% weight loss were all above 460 °C in air or nitrogen atmospheres. In comparison with a nonfluorinated polyimide series based on 1,4‐bis(4‐aminophenoxy)‐2,5‐di‐tert‐butylbenzene, the 5 series showed better solubility and lower color intensity, dielectric constants, and moisture absorption. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2272–2284, 2004 相似文献
15.
Youngtai Yoo Larry K. Johnson Stephen N. Falling Jeremy R. Lizotte Timothy E. Long 《Journal of polymer science. Part A, Polymer chemistry》2002,40(16):2789-2798
Accelerated crosslinking of novel poly(3,4‐epoxy‐1‐butene) (3,4‐PEPB) oligomers in the presence of a cobalt‐based redox catalyst was investigated. Previous studies using model compounds, 3,4‐dimethoxy‐1‐butene and 1,4‐dimethoxy‐2‐butene, suggested that maleation of hydroxyl‐terminated 3,4‐PEPB oligomers would result in more rapid crosslinking in thin films. Novel maleated oligomers offered a unique combination of both electron‐rich and electron‐poor olefinic sites, and quantitative maleation significantly increased the crosslinking rate of 3,4‐PEPB. Efficient copolymerization between terminal maleate groups and olefinic groups in the repeating unit was proposed to account for accelerated crosslinking rates. Furthermore, the addition of novel reactive diluents, such as maleic acid mono‐ethyl ester, also effectively improved the 3,4‐PEPB crosslinking rate. Sol fraction measurements as a function of coating thickness revealed that the crosslinking rate versus oxygen diffusion was less significant for the maleated oligomers because of the presence of reactive electron‐poor olefins. Sol fractions were constant for catalyst concentrations greater than 0.25–0.50 wt % (as compared with oligomer feed). This observation suggested that a redox process was not a dominant factor in determining crosslinking rates at various experimental conditions. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2789–2798, 2002 相似文献
16.
Le Roux E Nief F Jaroschik F Törnroos KW Anwander R 《Dalton transactions (Cambridge, England : 2003)》2007,(42):4866-4870
Homoleptic complexes Ln(AlMe(4))(3) (Ln = La, Nd) can be straightforwardly utilized in salt metathetic exchange reactions with potassium 2,3,4,5-tetramethylphospholide (KTmp) or 3,4-dimethyl-2,5-bis(trimethylsilyl)phospholide (KDsp) affording monophosphacyclopentadienyl hydrocarbyl complexes (eta(5)-PC(4)Me(4))Ln(AlMe(4))(2) and [eta(5)-PC(4)Me(2)(SiMe(3))(2)]Ln(AlMe(4))(2) (Ln = La, Nd). The solid-state structures reveal distinct metal size effects as evidenced by X-ray diffraction analyses of monomeric neodymium Tmp and Dsp derivatives as well as the dimeric lanthanum Tmp complex. Dimerization is accomplished by intermolecular P --> La donor contacts. Upon activation with [PhMe(2)NH][B(C(6)F(5))(4)] the monophosphacyclopentadienyl complexes initiate the polymerization of isoprene producing 1,4-trans-polyisoprene (tPIP > 87%) with moderate activity (approximately 30 kg(PIP) mol(Ln)(-1) h(-1)). 相似文献
17.
Shinn‐Horng Chen Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2004,42(23):5900-5910
To investigate the effect of trifluoromethyl groups in enhancing electron affinity of aromatic oxadiazole and triazole chromophores, we prepared four new copoly(aryl ether)s ( P1 – P4 ) consisting of bis(3‐(trifluoromethyl) phenyl)‐1,3,4‐oxadiazole (ETO) or bis(3‐(trifluoromethyl)phenyl)‐4‐(4‐hexyloxyphenyl)‐4H‐1,2,4‐triazole (ETT) segments and hole‐transporting segments [2,5‐distyrylbenzene (HTB) or bis(styryl)fluorine (HTF)]. Molecular spectra (absorption and photoluminescence) and cyclic voltammetry were used to investigate their optical and electrochemical properties. The emissions of P1 – P4 are dominated by the hole‐transporting fluorophores with longer emissive wavelengths around 442–453 nm via efficient excitation energy transfer. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of P1 – P4 , estimated from electrochemical data, are ?5.15, ?5.18, ?5.30, ?5.27, ?3.39, ?3.49, ?3.36, and ?3.48 eV, respectively. The LUMO levels of ETO and ETT segments are significantly reduced to ?3.39~?3.36 eV and ?3.48~?3.49 eV, respectively, as compared with ?2.45 eV of P5 containing a 2,5‐diphenyl‐1,3,4‐oxadiazole segment. Moreover, electron and hole affinity can be enhanced simultaneously by introducing isolated hole‐ and electron‐transporting segments in the backbone. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5900–5910, 2004 相似文献
18.
M. L. Keshtov S. A. Kuklin D. Y. Godovsky A. R. Khokhlov R. Kurchania F. C. Chen Emmanuel N. Koukaras G. D. Sharma 《Journal of polymer science. Part A, Polymer chemistry》2016,54(1):155-168
A novel D–A1–D–A2 copolymer denoted as P1 containing two electron withdrawing units based on benzothiadiazole (BT) and 9‐(2‐octyldodecyl)?8H‐pyrrolo[3,4‐b] bisthieno[2,3‐f:3′,2′‐h]quinoxaline‐8,10(9H)–dione (PTQD) units was synthesized and characterized. The resulting copolymer exhibits a broad‐absorption spectrum, relatively deep lying HOMO energy level (?5.44 eV) and narrow optical bandgap (1.50 eV). Bulk heterojunction (BHJ) polymer solar cells (PSCs) based on P1 as donor and PC71BM as acceptor with optimized donor to acceptor weight ratio of 1:2 and processed with DIO/CB solvent showed good photovoltaic performance with power conversion efficiency of 6.21% which is higher than that of the device processed without solvent additive (4.40%). The absorption and morphology investigations of the active layers indicated that structural and morphological changes were induced by the solvent additive. This higher power conversion efficiency could be mainly attributed to the absorption enhancement and improved charge transported in the active layer induced by the better nanoscale morphology of the active layer. This study demonstrated that a copolymer with two different acceptor moieties in the backbone may be promising candidate as donor copolymer for solution processed BHJ PSCs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 155–168 相似文献
19.
Ozlem Turkarslan Metin Ak Cihangir Tanyeli Idris M. Akhmedov Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》2007,45(19):4496-4503
A copolymer of 1‐(4‐fluorophenyl)‐2,5‐di(thiophen‐2‐yl)‐1H‐pyrrole (FPTP) with 3,4‐ethylene dioxythiophene (EDOT) was electrochemically synthesized and characterized. While poly(FPTP) (P(FPTP)) has only two colors in its oxidized and neutral states (blue and yellow), its copolymer with EDOT has five different colors (purple, red, light gray, green, and blue). Electrochromic devices based on P(FPTP‐co‐EDOT) and poly(3,4‐ethylenedioxythiophene) (PEDOT) were constructed and characterized. The oxidized state of the device shows blue color whereas it shows purple for the reduced state. At several potentials the device has good transparency with green and gray colors. Maximum contrast (Δ%T) and switching time of the device were measured as 23% and 1.1 s at 555 nm. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4496–4503, 2007 相似文献
20.
William J. Patterson Samuel P. McManus Charles U. Pittman 《Journal of polymer science. Part A, Polymer chemistry》1974,12(4):837-850
A new monomer, 1,1′-bis(dimethylaminodimethylsilyl)ferrocene, was synthesized by two routes and polymerized with three aryl disilanols: dihydroxydiphenylsilane, 1,4-bis(hydroxydimethylsilyl)benzene, and 4,4′-bis(hydroxydimethylsilyl)biphenyl, yielding three different polysiloxanes. Melt polymerizations carried out at 1 torr pressure and 100°C resulted in the highest molecular weight polymers. Intramolecular cyclization competed with intermolecular chain extension in polymerization of the bis(aminosilane) with dihydroxydiphenylsilane, resulting in isolation of a bridged derivative, 1,3,5-trisila-2,4-dioxa-1,1,5,5-tetramethyl-3,3-diphenyl[5]ferrocenophane. Cyclization did not compete significantly during the formation of polymers from this bisaminosilane and the two remaining diols, as evidenced by higher yields and greater molecular weights. These polymers could be cast as tough flexible films, and fibers could be drawn from their melts. TGA and DSC data showed the polymer formed from 1,1′-bis(dimethylaminodimethylsilyl)ferrocene and 1,4-bis(hydroxydimethylsilyl)benzene to be at least as thermally stable as an arylene siloxane polymer which differed from the ferrocenylsiloxane structure only in the replacement of the ferrocene moiety with a p-substituted phenylene linkage. The ferrocene-containing polymers were generally hydrolytically stable under conditions of refluxing THF–H2O(10 : 1) for 1 hr. The polymer-forming reaction was found to follow second-order kinetics, and the specific rate constants for formation of two of the polymers were measured. 相似文献