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Ladder polymer

Wei Gao, Qiaoshi An, Cheng Zhong, Zhenghui Luo, Ruijie Ming, Miao Zhang, Yang Zou, Feng Liu, Fujun Zhang, Chuluo Yang
Isomers with small structural changes usually exhibit different properties. Rationally designing isomers of some high-performance SMAs can further enhance their function. In this work, an asymmetrical small molecule acceptor (SMA) MeIC1 isomerized from MeIC is reported. Compared with the symmetrical MeIC, the asymmetrical isomer showed almost the same absorption range but an elevated LUMO energy level and simultaneously enhanced π-π stacking and electron mobility by replacing the thieno[3,2- b ]thiophene unit with a larger sized dithieno[3,2- b :2',3'- d ]thiophene unit in the ladder-type core of MeIC...
November 14, 2018: Chemical Science
Qichun Zhang, Xiaobing Fan, Jianhong Gao, Wei Wang, Shengqiang Xiao, Chun Zhan, Xinhui Lu
A ladder-type nonacyclic arene (bis(thieno[3,2-b]thieno)cyclopentafluorene (BTTF)) has been designed and synthesized through fusing thienothiophenes with the fluorene core from the synthon of dimethyl 9,9-dioctyl-2,7-bis(thieno[3,2-b]thiophen-2-yl)fluorene-3,6-dicarboxylate. With BTTF as the central donor unit, a novel acceptor-donor-acceptor (A-D-A) type non-fullerene small molecule acceptor (BTTFIC) was prepared with 1,1-dicyanomethylene-3-indanones (IC) as the peripheral acceptor units. The energy level of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of BTTFIC locate at -5...
December 10, 2018: Chemistry, An Asian Journal
Chun-Kai Wang, Bing-Huang Jiang, Yu-Wei Su, Ru-Jong Jeng, Yu-Jian Wang, ChihPing Chen, Ken-Tsung Wong
In this study, we synthesized 5,11-dihexyl-4,4,10,10-tetraoctylbenzo[1,2-b:4,5-b']bisthieno[4´´,5´´-b´´:4´´´,5´´´-b´´´]silolo[2´´,3´´-d:2´´´,3´´´-d´]thiophene (ArSi) as a ladder-type electron-rich core for the preparation of three A-D-A-type nonfullerene acceptors (NFAs)-ArSiID, ArSiID-F, and ArSiID-Cl-featuring (3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID), 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID-F), and 2-(5,6-dichloro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (ID-Cl) as peripheral electron-poor units, respectively...
December 7, 2018: ACS Applied Materials & Interfaces
Shuxun Cui, Song Zhang, Hu-Jun Qian, Zhong-Yuan Lu, Zhonghua Liu, Haiming Zhang, Lifeng Chi, Hongyu Ju
Since the discovery of amorphous red phosphorus (a-red P) in 1847, a number of possible structures of a-red P have been proposed. However, the exact molecular structure of a-red P is not determined yet due to the amorphous nature. Here in this study, we utilize several methods to investigate some basic properties of a-red P, which are helpful to determine the structure. The experimental results from scanning tunneling microscopy (STM) and gel permeation chromatography (GPC) confirm that a-red P is a linear inorganic polymer with a broad molecular weight distribution...
December 2, 2018: Angewandte Chemie
Zhan-Biao Chen, Pei-Yan Huang, Zheng-Wei Li, Xin-Yan Guo, Chen Zhao, Xiao-Hong Zheng, Yi Yang
Vehicle overload is detrimental to bridges and traffic safety. This paper presents a study on the fatigue performance of typical reinforced concrete (RC) beams of highway bridges under vehicle overload. A definition method of vehicle overload and a construction method of overload ladder spectrum were first proposed based on traffic data acquisition, statistical analysis and structural calculation of the highway bridges in Guangzhou. A fatigue experimental method was also proposed with the three-ladder vehicle overload spectrum, and the fatigue tests of 15 RC beams strengthened with carbon fiber reinforced polymer (CFRP) under three loading levels were then carried out...
October 3, 2018: Sensors
Marie-Claire Ockfen, Michael Forster, Ullrich Scherf
A synthetic route to solubilized graphenic nanoribbons (GNRs) by oxidation of methylene-bridged, aromatic ladder polymers is presented. Hereby, the ladder polymer precursors are finally 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (or DDQ) oxidized into the desired GNRs. However, a detailed UV-vis analysis shows already partial oxidation/dehydrogenation during aqueous work-up under loss of ≈50% of the bridgehead hydrogens as well as some indications for overoxidation with DDQ under formation of quinoid carbonyl defects, additionally driven by a reduction of the number of quinoid (quinodimethane) structural units...
September 24, 2018: Macromolecular Rapid Communications
Wen Jie Ong, Timothy M Swager
Dynamic covalent chemistry, with its ability to correct synthetic dead-ends, allows for the synthesis of elaborate extended network materials in high yields. However, the limited number of reactions amenable to dynamic covalent chemistry necessarily confines the scope and functionality of materials synthesized. Here, we explore the dynamic and self-correcting nature of nucleophilic aromatic substitution (SN Ar), using ortho-aryldithiols and ortho-aryldifluorides that condense to produce redox-active thianthrene units...
October 2018: Nature Chemistry
Abdullah F Alahmadi, Roger A Lalancette, Frieder Jäkle
A new B-N functionalized polyaromatic building block for conjugated hybrid polymers is developed. Bromine-functionalized dipyridylfluorene is first subjected to Lewis-base-directed electrophilic borylation and subsequently incorporated into conjugated polymers via transition-metal-catalyzed cross-coupling reactions. The borane monomer exhibits bright blue luminescence in solution, as a result of the rigid ladder-type structure generated upon electrophilic borylation. Yamamoto coupling gives rise to a homopolymer and Stille coupling to a vinylene-bridged copolymer...
August 3, 2018: Macromolecular Rapid Communications
Stephanie A Smith, Yan Wang, James H Morrissey
PAGE is often used to resolve inorganic polyphosphates (polyP), but unfortunately polyP size ladders are not commercially available. Since several dyes that are commonly used to detect nucleic acids in gels also stain polyP, we examined the utility of commercially available DNA size ladders for estimating polyP polymer lengths by gel electrophoresis. Narrow size fractions of polyP were prepared and their polymer lengths were quantified using NMR. Commercially available DNA ladders and these polyP fractions were then subjected to PAGE to determine the relationship between migration of DNA vs polyP, which was found to be: log10 (dsDNA length in bp) = 1...
October 2018: Electrophoresis
Marco Servalli, Nils Trapp, A Dieter Schlüter
In this work we present one of the rare cases of single-crystal-to-single-crystal (SCSC) linear polymerizations, resulting in a novel ladder-type polymer. The polymerization is based on the photoinduced [4+4]-cycloaddition reactions between trifunctional anthracene-based monomers. The careful design of the monomer anthraphane-tri(OMe), results in perfectly stacked anthracene pairs in the crystal structure, with Schmidt's distances d=3.505-3.666 Å and shift s=1.109 Å, allowing a selective linear polymerization in quantitative yields and in a matter of minutes, without compromising the integrity of the single crystals...
October 9, 2018: Chemistry: a European Journal
Basudeb Dutta, Arka Dey, Chittaranjan Sinha, Partha Pratim Ray, Mohammad Hedayetullah Mir
A pair of 4-(1-naphthylvinyl)pyridine (4-nvp) ligands has been successfully aligned in head-to-tail fashion in a one-dimensional (1D) double chain ladder polymer [Cd(adc)(4-nvp)2 (H2 O)] n (1; H2 adc = acetylenedicarboxylic acid) that undergoes a photochemical [2 + 2] cycloaddition reaction accompanied by single-crystal to single-crystal (SCSC) structural transformation from a 1D chain to a 2D layer structure. These structural changes have a significant impact on the conductivity and Schottky nature of the compound...
July 16, 2018: Inorganic Chemistry
Jianhua Chen, Kun Yang, Xin Zhou, Xugang Guo
The fusion of heteroaromatic rings into ladder-type heteroarenes can stabilize frontier molecular orbitals and lead to improved physicochemical properties that are beneficial for applications in various optoelectronic devices. Thus, ladder-type heteroarenes, which feature highly planar backbones and well-delocalized π conjugation, have recently emerged as a promising type of organic semiconductor with excellent device performance in organic photovoltaics (OPVs) and organic field-effect transistors (OFETs)...
September 17, 2018: Chemistry, An Asian Journal
Zhi-Min Li, Yu Qiao, Chun-Bo Liu, Yan-Feng Zhou, Xiu-Yan Wang, Paul A Charpentier, Guang-Bo Che, William Z Xu, Li-Hui Liu, En-Wei Zhu
Five highly stable coordination polymers assembled by 2-(2-carboxyphenyl)imidazo(4,5-f)-(1,10)phenanthroline (2-HNCP) and different aromatic carboxylic acid ligands, namely, [Pb(2-NCP)(L1)]n (1), [Pb2(2-NCP)2(L2)]n·2nH2O (2), [Pb2(2-NCP)2(L2)]n (3), [Pb(2-NCP)(L3)0.5]n (4) and [Pb2(2-NCP)2(L4)]n (5), where HL1 = pyridine-4-carboxylic acid, H2L2 = 2-amino-1,4-benzenedicarboxylic acid, H2L3 = 1,4-benzenedicarboxylic acid and H2L4 = 2-hydroxy-1,4-benzenedicarboxylic acid, have been synthesized under hydrothermal conditions...
June 12, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Zsanett Dorkó, Anett Nagy-Szakolczai, Blanka Tóth, George Horvai
One of the main reasons for making molecularly imprinted polymers (MIPs) has been that MIPs interact selectively with a specific target compound. This claim is investigated here with the example of a widely used type of noncovalent MIP, the MIP for the beta blocker propranolol. Adsorption isotherms of this MIP and of a nonimprinted control polymer (NIP), respectively, have been measured with a series of compounds in the porogen solvent acetonitrile. The results, visualized as "selectivity ladders", show that the MIP binds propranolol and many other amines better than the NIP does, but the selectivity of the MIP is actually inferior to that of the NIP...
May 29, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Wei Gao, Miao Zhang, Tao Liu, Ruijie Ming, Qiaoshi An, Kailong Wu, Dongjun Xie, Zhenghui Luo, Cheng Zhong, Feng Liu, Fujun Zhang, He Yan, Chuluo Yang
In this work, an effectual strategy of constructing polar small molecule acceptors (SMAs) to promote fill factor (FF) of nonfullerene polymer solar cells (PSCs) is first reported. Three asymmetrical SMAs of IDT6CN, IDT6CN-Th, and IDT6CN-M, which own large dipole moments, are designed and synthesized. The PSCs based on three polar SMAs exhibit apparently higher FFs compared with their symmetrical analogues. The asymmetrical design strategy accompanied with side chain and end group engineering makes IDT6CN-Th- and IDT6CN-M-based nonfullerene PSCs achieve high power conversion efficiency with FFs approaching 77%...
June 2018: Advanced Materials
Yingfeng Wang, Han Guo, Alexandra Harbuzaru, Mohammad Afsar Uddin, Iratxe Arrechea-Marcos, Shaohua Ling, Jianwei Yu, Yumin Tang, Huiliang Sun, Juan Teodomiro López Navarrete, Rocio Ponce Ortiz, Han Young Woo, Xugang Guo
Development of high-performance unipolar n-type organic semiconductors still remains as a great challenge. In this work, all-acceptor bithiophene imide-based ladder-type small molecules BTI n and semiladder-type homopolymers PBTI n ( n = 1-5) were synthesized, and their structure-property correlations were studied in depth. It was found that Pd-catalyzed Stille coupling is superior to Ni-mediated Yamamoto coupling to produce polymers with higher molecular weight and improved polymer quality, thus leading to greatly increased electron mobility (μe )...
May 16, 2018: Journal of the American Chemical Society
Liang Yu, Shaozhong Zeng, Xierong Zeng, Xiaohua Li, Hongliang Wu, Yuechao Yao, Wenxuan Tu, Jizhao Zou
Facile synthesis of carbon materials with high heteroatom content, large specific surface area (SSA) and hierarchical porous structure is critical for energy storage applications. In this study, nitrogen and oxygen co-doped clews of carbon nanobelts (NCNBs) with hierarchical porous structures are successfully prepared by a carbonization and subsequent activation by using ladder polymer of hydroquinone and formaldehyde (LPHF) as the precursor and ammonia as the activating agent. The hierarchical porous structures and ultra-high SSA (up to 2994 m² g−1 ) can effectively facilitate the exchange and transportation of electrons and ions...
April 4, 2018: Materials
Max Marcus, Jonathan D Milward, Anna Köhler, William Barford
We use a Frenkel-Holstein model of uncoupled chains in the adiabatic limit to simulate the optical spectra of the conjugated polymer ladder-type poly( p-phenylene) derivative (MeLPPP), which is a planar conjugated polymer with especially low interchain interactions. The theoretical calculations correctly reproduce the vibronic spectra and yield reasonable torsion angles between adjacent phenyl rings. The success of this approach indicates that, in contrast to interchain coupling, the strong electronic coupling along a polymer chain is more appropriately described in the adiabatic limit...
April 12, 2018: Journal of Physical Chemistry. A
Tristan Neumann, Magdalena Ceglarska, Luzia S Germann, Michał Rams, Robert E Dinnebier, Stefan Suckert, Inke Jess, Christian Näther
Reaction of Ni(NCS)2 with 4-aminopyridine in different solvents leads to the formation of compounds with the compositions Ni(NCS)2 (4-aminopyridine)4 (1), Ni(NCS)2 (4-aminopyridine)2 (H2 O)2 (2), [Ni(NCS)2 (4-aminopyridine)3 (MeCN)]·MeCN (3), and [Ni(NCS)2 (4-aminopyridine)2 ] n (5-LT). Compounds 1, 2, and 3 form discrete complexes, with octahedral metal coordination. In 5-LT the Ni cations are linked by single thiocyanate anions into chains, which are further connected into layers by half of the 4-aminopyridine coligands...
March 19, 2018: Inorganic Chemistry
Chin-Lung Chung, Hsieh-Chih Chen, Yun-Siou Yang, Wei-Yao Tung, Jian-Wei Chen, Wen-Chang Chen, Chun-Guey Wu, Ken-Tsung Wong
Three novel donor-acceptor alternating polymers containing ladder-type pentacyclic heteroacenes (PBo, PBi, and PT) are synthesized, characterized, and further applied to organic field effect transistors (OFETs) and polymer solar cells. Significant aspects of quinoidal characters, electrochemical properties, optical absorption, frontier orbitals, backbone coplanarity, molecular orientation, charge carrier mobilities, morphology discrepancies, and the corresponding device performances are notably different with various heteroarenes...
February 21, 2018: ACS Applied Materials & Interfaces
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