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Ladder polymer

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...
July 16, 2018: Electrophoresis
Marco Servalli, Nils Trapp, 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...
July 8, 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
Xugang Guo, Jianhua Chen, Kun Yang, Xin Zhou
The fusion of heteroaromatic rings into ladder-type heteroarenes can stabilize frontier molecular orbitals and lead to improved physicochemical properties, which are beneficial for applications in various optoelectronic devices. Hence, ladder-type heteroarenes, which feature highly planar backbones and well delocalized π-conjugation, recently have emerged as a type of promising organic semiconductors with excellent device performance in organic photovoltaics and organic field-effect transistors. In this Focus Review, we summarize the recent advances in ladder-type heteroarenes based organic semiconductors including hole-transporting and electron-transporting molecular semiconductors as well as fully ladder-type conjugated polymers towards their applications in organic photovoltaics and field-effect transistor...
June 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
Hengda Sun, Mikhail Vagin, Suhao Wang, Xavier Crispin, Robert Forchheimer, Magnus Berggren, Simone Fabiano
Organic electrochemical transistors (OECTs) have been the subject of intense research in recent years. To date, however, most of the reported OECTs rely entirely on p-type (hole transport) operation, while electron transporting (n-type) OECTs are rare. The combination of efficient and stable p-type and n-type OECTs would allow for the development of complementary circuits, dramatically advancing the sophistication of OECT-based technologies. Poor stability in air and aqueous electrolyte media, low electron mobility, and/or a lack of electrochemical reversibility, of available high-electron affinity conjugated polymers, has made the development of n-type OECTs troublesome...
March 2018: Advanced Materials
Chao Wang, Chao Liu, Hong-Rui Tian, Lei-Jiao Li, Zhong-Ming Sun
The exploitation of new titanium-based coordination polymers (Ti CPs) with high crystallinity is difficult but highly desirable for their potential applications in photocatalysis. Herein, a cluster-cooperative assemble strategy is developed to synthesize Ti CPs. By utilizing various bifunctional ligands containing carboxylate acids and N-donor groups, we successfully assembled the zero-dimensional (0D) [(Ti3 O)(iPrO)8 ]2+ or [(Ti4 O2 )(iPrO)6 ]6+ clusters into one-dimensional (1D) tube-, ribbon-, or helical chain-shape architectures, two-dimensional (2D) layered structures, and a rare parallel 2D→three-dimensional (3D) polycatenation framework with various copper iodide dopants, including rhombus- or wing-shaped Cu2 I2 and tetrahedron- or ladder-shaped Cu4 I4 ...
February 26, 2018: Chemistry: a European Journal
Hua-Chun Wang, Qing-Ya Li, Hong-Bo Yin, Xiancheng Ren, Kai Yao, Yonghao Zheng, Yun-Xiang Xu
Two pairs of polymer donor materials based on indacenodithiophene (IDT) and indacenodithieno[3,2-b]thiophene (IDTT) as the donor units are synthesized. Thiophene or selenophene is introduced as the π-bridge units and electron-deficient fluorine-substituted quinoxaline is used as acceptor unit. Selenophene-containing polymers PIDT-DFQ-Se and PIDTT-DFQ-Se show redshifted absorption and narrower bandgaps. Combined with IDTT donor unit, PIDTT-DFQ-Se shows the highest absorption coefficient. Both the IDTT unit and selenophene unit have positive effects on the hole mobilities, making PIDTT-DFQ-Se the highest one...
January 2018: Macromolecular Rapid Communications
Goutam Ghosh, Mithun Paul, Tsuneaki Sakurai, Wakana Matsuda, Shu Seki, Suhrit Ghosh
Herein, the self-assembly of a few 1,3-dihydroxyl functionalized naphthalene diimide (NDI) derivatives has been reported with particular emphasis on the impact of chirality on gelation and the effect of self-assembly on charge-carrier mobility. A nonconventional gelator (R)-NDI, devoid of any long alkyl chains, exhibited spontaneous gelation in tetra-chloroethylene (TCE). Based on X-ray crystallography and powder X-ray diffraction studies, it was established that a ladder-like hydrogen-bonded chain formation between the 1,3-dihydroxyl group leads to the fibrillar structures with preferential helicity...
February 6, 2018: Chemistry: a European Journal
Karol Wolski, Michał Szuwarzyński, Szczepan Zapotoczny
A facile strategy for the synthesis of conjugated polyelectrolyte brushes grafted from a conductive surface is presented. Such brushes form a platform of molecular wires oriented perpendicularly to the surface, enabling efficient directional transport of charge carriers. As the synthesis of conjugated polymer brushes using chain-growth polymerization via a direct "grafting from" approach is very challenging, we developed a self-templating surface-initiated method. It is based on the formation of multimonomer template chains in the first surface-initiated polymerization step, followed by the second polymerization leading to conjugated chains in an overall ladder-like architecture...
March 1, 2015: Chemical Science
Shuguang Wen, Yao Wu, Yingying Wang, Yi Li, Ling Liu, Huanxiang Jiang, Zhitian Liu, Renqiang Yang
In recent years, nonfullerene acceptors have attracted much attention, owing to their great potential for use in high-performance polymer solar cells.The ladder-type building block, pyran-bridged indacenodithiophene (PDT), was used for constructing A-D-A nonfullerene acceptors through introduction of oxygen atoms into an indacenodithiophene (IDT) unit. The synthesis of PDT is accomplished by a BBr3 -mediated tandem cyclization-deprotection reaction to construct the pyran ring. Hence, molecular acceptor PTIC was synthesized and used in a polymer solar cell device...
January 23, 2018: ChemSusChem
Yu-Tang Hsiao, Chia-Hua Li, Shao-Ling Chang, Soowon Heo, Keisuke Tajima, Yen-Ju Cheng, Chain-Shu Hsu
In this research, a haptacyclic carbazole-based dithienocyclopentacarbazole (DTCC) ladder-type structure was formylated to couple with two 1,1-dicyanomethylene-3-indanone (IC) moieties, forming a new nonfullerene acceptor DTCCIC-C17 using a bulky branched 1-octylnonayl side chain at the nitrogen of the embedded carbazole and four 4-octylphenyl groups at the sp3 -carbon bridges. The rigid and coplanar main-chain backbone of the DTCC core provides a broad light-absorbing window and a higher-lying LUMO energy level, whereas the bulky flanked side chains reduce intermolecular interactions, making DTCCIC-C17 amorphous with excellent solution processability...
December 6, 2017: ACS Applied Materials & Interfaces
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