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872.
Newayemedhin A. Tegegne Zelalem Abdissa Wendimagegn Mammo Mats R. Andersson Derck Schlettwein Heinrich Schwoerer 《Journal of polymer science. Part A, Polymer chemistry》2018,56(21):1475-1483
A low band gap copolymer, P2TI (Eg = 1.6.eV), with bithiophene as donor and isoindigo as acceptor units is designed and synthesized by the direct arylation polycondensation (DAP) method. Absorbance of the polymer spans from 300 to 780 nm. It exhibits an absorption coefficient (ε) of 96 L/g cm in solution at its maxima. A HOMO level of −5.42 eV and LUMO level of −3.72 eV is measured by square wave voltammetry. ITO-free solar cells fabricated using a P2TI :PCBM71 bulk heterojunction shows a moderate efficiency of 1.02% with a high open circuit voltage of 0.81 V. An intramolecular charge transfer state is found in the relaxation of P2TI in solution, which is generated with a time constant of 2 ps as measured by femtosecond-transient absorption spectroscopy. Charge carriers were generated in <250 fs in P2TI: PCBM71 films. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1475–1483 相似文献
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Johannes A. M. Hepperle Heinrich Luftmann Armido Studer 《Journal of polymer science. Part A, Polymer chemistry》2012,50(11):2150-2160
The article describes unprecedented nitroxide‐mediated radical polymerization of methyl and phenyl vinyl ketone (MVK and PVK) using a sterically highly hindered alkoxyamine as initiator/regulator. It is shown that controlled polymerization of PVK is far more difficult to achieve than controlled MVK polymerization. Whereas for MVK high conversion resulting in polyvinyl ketone with low polydispersity index is readily obtained, the PVK polymerization provides good results only in the presence of free nitroxide and styrene as additives. Vinyl ketone polymerizations are analyzed by ESI mass spectrometry. These MS studies provide insights into the problems associated with the controlled nitroxide‐mediated polymerization of PVK. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
875.
Dr. Jens Voskuhl Dr. Christian Wendeln M. Sc. Frank Versluis M. Sc. Eva‐Corinna Fritz M. Sc. Oliver Roling M. Sc. Harshal Zope Dr. Christian Schulz Dipl.‐Phys. Stefan Rinnen Prof. Dr. Heinrich F. Arlinghaus Prof. Dr. Bart Jan Ravoo Dr. Alexander Kros 《Angewandte Chemie (International ed. in English)》2012,51(50):12616-12620
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Stefan Baudis S. Clark Ligon Konstanze Seidler Guenter Weigel Christian Grasl Helga Bergmeister Heinrich Schima Robert Liska 《Journal of polymer science. Part A, Polymer chemistry》2012,50(7):1272-1280
Thermoplastic polyurethane (TPU) elastomers with biodegradable chain extenders were synthesized and tested for mechanical performance and biocompatibility. The design of the TPUs was based on structural modification of a mechanically appropriate aromatic isocyanate‐based TPU. As the aromatic isocyanate was substituted with a less toxic but also less “hard” aliphatic isocyanate, the chain extender plays an important role on the mechanical properties. Here, the terephthalate ester chain extender was found to work better than hydroxyl ethyl lactate in providing polymers with mechanical properties similar to commercial aromatic isocyanate‐based TPUs. The polymers were degraded in aqueous solutions at elevated temperatures and compared to polylactic acid (PLA) to partially simulate biodegradation. The lactate‐based TPUs degraded about twice as fast as PLA while the terephthalate‐based TPU degraded much more slowly. The latter material was processed by electrospinning to give a tubular graft approximately the size of a large rat blood vessel. Initial results from implantation of these TPUs into rats are promising and indicate that biodegradation occurs and is likely beneficial to cell proliferation. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
879.
Deeb Taher Firas Awwadi Mohammad El-khateeb Heinrich Lang 《Transition Metal Chemistry》2012,37(6):601-604
New homo-trimetallic complexes of general formula?1,1??-fc[SeFeCp(CO)2]2 (fc?=?Fe(??5-C5H4)2) are accessible in high yield by the reaction of 1,1??-fc(SeLi)2, which is generated from 1,1??-fc(SeSiMe3)2 and n-BuLi, with two equivalents of CpFe(CO)2I. Photolytic CO-substitution reactions of the organoiron diselenolate with bis-phosphines at ?50?°C using 1:2 (metal/ligand) molar ratio afforded 1,1??-fc(SeFeCp(P^P)2. All these complexes were characterized by physicochemical and spectroscopic methods. 相似文献
880.