Charge Transfer In Polymers Research Articles

Intramolecular Charge-Transfer Polymers between Dithiafulvene and Pyridinium Units: Conjugative Effect through Saturated Polymethylene Chains

Abstract New polymers containing an intramolecular charge-transfer (ICT) structure (pyridinium–dithiafulvene–pyridinium) in the main chain were prepared. UV–vis measurements of the polymers suggested that conjugative effects occur through saturated polymethylene chains, and that such effects are enhanced as the length of the spacer polymethylene chain decreases. Polyviologens showed small but similar conjugations in their UV–vis measurements. A PM3 calculation of 1,1′-(1,2-ethanediyl)bis(pyridinium) suggested that low-lying LUMO resulting from an interaction between the σ* of the ethylene unit and π* of the pyridinium moiety affords the conjugative effect. The PM3 calculations and the UV–vis results show that the incorporation of the ICT moiety in the polymeric framework increases the conjugative effect through the polymethylene chains. The redox and conducting properties of the ICT polymers were also investigated. Both studies gave some implications of the conjugative effects of the polymers.

Charge-transfer doping of poly(3-alkyl-2,2′-bithiophene)

Spin-cast films of the title polymer, a highly ordered, flexible, and soluble polythiophene, can be doped with solutions of dichlorodicyanoquinone (DDQ) to produce a highly conducting material. The doped films of the polybithiophene exhibit strong bipolaronic absorptions, consistent with the formation of charge-transfer polymers. Weaker dopants, e. g., benzoquinone, are not effective. The use of organic dopants of this type provides a superior method for production of stable conductive materials. Spectroscopic and thin-film x-ray diffraction data support a charge-transfer mechanism.

Ultrafast Nonlinear Optical Properties of Charge-Transfer Polymers

Charge-transfer polymers are a new class of nonlinear optical materials which can be used for generating femtosecond holographic gratings. Using semiconducting polymers sensitized with varying concentrations of C 60, holographic gratings were recorded by individual ultrafast laser pulses; the diffraction efficiency and time decay of the gratings were measured using nondegenerate four-wave mixing. Using a figure of merit for dynamic data processing, the temporal diffraction efficiency, this new class of materials exhibits between two and 12 orders of magnitude higher response than previous reports. The charge-transfer range at polymer/ C 60 interfaces was further studied using transient absorption spectroscopy. The fact that charge transfer occurs in the picosecond-time scale in bilayer structures (thickness 200 Å) implies that diffusion of localized excitations to the interface is not the dominant mechanism; the charge-transfer range is a significant fraction of the film thickness. From analysis of the excited state decay curves, we estimate the charge-transfer range to be 80 Å and interpret that range as resulting from quantum delocalization of the photoexcitations.

Ultrafast holography using charge-transfer polymers

Charge-transfer polymers are a new class of nonlinear optical materials which can be used for generating femtosecond holographic gratings. Using semiconducting polymers sensitized with varying concentrations of C 60, holographic gratings were recorded by individual ultrafast laser pulses; the diffraction efficiency and time decay of the gratings were measured using non-degenerate four-wave mixing. Using a figure of merit for dynamic data processing, the temporal diffraction efficiency, this new class of materials exhibits between two and 12 orders of magnitude higher response than any other class of material. The high quantum efficiency and metastability of the charge transfer enables tuning of the decay dynamics by controlling the concentration of acceptors in the blend.

Synthesis, Characterization, and Properties of High Molecular Weight Poly(methylated ferrocenylsilanes) and Their Charge Transfer Polymer Salts with Tetracyanoethylene

A series of poly(ferrocenylsilanes) with methylated cyclopentadienyl (Cp) rings [Fe(η-C5MexH4-x)(η-C5MeyH4-y)SiMe2]n (2a−e) (a, x = 0, y = 0; b, x = 1, y = 1 (Cp−Me groups at random positions); c, x = 1, y = 1 (Cp−Me groups at 3,3‘ positions); d, x = 4, y = 0; e, x = 4, y = 4) have been prepared by thermal ring-opening polymerization (TROP) of the corresponding silicon-bridged [1]ferrocenophanes Fe(η-C5MexH4-x)(η-C5MeyH4-y)SiMe2 (1a−e). DSC analysis revealed that increasing methylation of the ferrocenophane Cp rings resulted in increasing onset temperatures for the TROP reaction but did not significantly affect the enthalpy of polymerization, ΔHp. Poly(ferrocenylsilanes) 2b−d were soluble in common organic solvents and were characterized by IR, 1H, 13C, and 29Si NMR spectroscopy, and elemental analysis. The molecular weights of these polymers were estimated to be in the range of Mw = 1.8 × 105 to 4.1 × 105 and Mn = 9.4 × 104 to 2.8 × 105 by GPC in THF versus polystyrene standards. The fully methylated poly(ferrocenylsilane) 2e was insoluble in common organic solvents and was characterized by IR, 13C and 29Si CP-MAS NMR, and elemental analysis. The electrochemical behavior of 2b−d in CH2Cl2 solution was investigated by cyclic voltammetry, and these polymers each exhibited two reversible oxidation waves, consistent with significant electronic interactions between the iron centers. Increasing Cp methylation led to the expected decrease in half-wave oxidation potentials, relative to nonmethylated 2a. DSC analysis showed that 2b−d exhibit weak glass transitions which shift to higher temperature with increasing methylation. No melting transitions were detected by DSC for these polymers, and WAXS analysis confirmed that the polymers were amorphous and indicated that the average interchain distance increases with increasing Cp methylation. TGA of 2a−d found decreasing thermal stability with regard to weight loss upon increasing methylation. The microstructure of polymer 2d provided insight into the polymerization mechanism and was consistent with polymerization via nonselective cleavage of Cp−Si (as opposed to Cp−Fe) bonds. The reactions of 2a, 2b, 2d, and 2e with tetracyanoethylene (TCNE) were investigated. Whereas 2a did not react, the Cp-methylated analogues 2b, 2d, and 2e yielded dark solids 3b, 3d, and 3e, which were soluble in polar organic solvents. IR and microanalytical data indicated that the products contain oxidized polymer and a mixture of polycyano counteranions. Bulk solid-state magnetic susceptibility data indicated that 3e obeys the Curie−Weiss law, with μeff = 2.0 μB, and θ = −1.1 K. In contrast to recent reports on TCNE-oxidized oligo(ferrocenylsilanes), no evidence was found for any long-range cooperative spin−spin interactions at low temperature.

π-Conjugated Charge Transfer Polymer Constituted of Electron-donating Thiophene and Electron-withdrawing Quinoxaline

Abstract Palladium-catalyzed polycondensation between 2,5-bis(trimethylstannyl)thiophene and 5,8-dibromoquinoxaline derivatives gives soluble new π-conjugated polymers, which exhibit absorption bands at 575 ± 30 nm assignable to intramolecular charge transfer bands and show the three-photon resonant third-order nonlinear optical susceptibility χ(3) of about 5 × 10−11 esu.

Recent developments in polymeric charge transfer complexes

AbstractThe recent literature on polymeric charge transfer complexes is reviewed with emphasis on the author's own work. After a definition of the area and a survey of investigations on the spatial arrangement of donor and acceptor sites in the solid state, a variety of applications of these complexes is presented. Electrically conductive polymers are excluded. These applications are: compatibilization of polymer blends, liquid crystalline supramolecular organization, new developments in photo‐conductivity, electroluminescence, nonlinear optical properties, photorefractivity and reversible optical storage.

Editorial: polymeric charge transfer complex

Editorial: polymeric charge transfer complex

Third-Harmonic Generation of Polymeric Charge-Transfer Complex Film

Nonlinear optical property of polymeric charge transfer complex was investigated in terms of the complex composition. The third-order nonlinear optical susceptibility X (3) 1111(-3ωω,ω,ω) of poly-n...

Slow relaxation of the spin doublet decamethylferrocenium cation as a probe for spin on organo-polycyanides, new organoferromagnets

The contributions of Mossbauer spectroscopy and susceptibility studies to the discovery of a variety of new and some cases unprecedented magnetic behavior in polymeric charge transfer salts are highlighted.

Mössbauer spectroscopy studies of magnetic ordering and slow paramagnetic relaxation in the helium-3 temperature range

Aspects of a carbon sorption pumped helium-3 cryostat are described with particular emphasis on applications to the study of weak exchange interactions between centers of delocalized electron spin density in a series of ionic fluorides of high spin iron (III). The novel vanishing of magnetic hyperfine splitting for T<1 K in certain charge transfer polymers based on polycyanide electron acceptors and decamethyl ferrocene is also discussed. In addition, source experiments for the ID-metamagnet Co(bipyridine) Cl2 are presented.

Electroactive charge transfer polymers from anodic coupling of dibenzo-crown ethers: Part III. Intrinsic redox properties and preliminary use as electrode modifiers

The intrinsic electrochemical properties of the poly(dibenzo-crown ethers) have been investigated. Thus, five different redox states have been pointed out and a detailed analysis of the doping and dedoping processes has been performed. Furthermore, a short account of these polymers as electrode modifiers is presented.

Electrical properties of chemically synthesized polypyrrole-halogen charge transfer complexes

Simultaneous chemical polymerization and oxidation of pyrrole have been initiated by halogens, iodine (I 2) and bromine (Br 2) at 0 to 4°C. The d.c. electrical conductivity (σ) of this new family of polymeric charge transfer complexes is of the order of 30 ohm -1 cm -1 at room temperature. σ was measured as a function of temperature between 300 and 150 K, using both standard four probe and voltage shorted compaction (VSC) techniques. A metallic temperature dependence of σ was observed for both complexes in the VSC measurements.

Electroactive charge-transfer polymers from anodic coupling of dibenzo-crown ethers Part II. Influence of the complexing properties of the polyether rings

A new family of electroactive redox polymers with triphenylene moieties linked two-dimensionally via polyether bridges, has been synthesized by anodic oxidation of dibenzo-crown ethers. The influence of the complexing properties of the polyether rings towards alkali metal cations and neutral guests were studied with regard to the electrochemical behaviour of the monomers themselves, as well as to the ionophoric properties of the polymers.

Polymer charge-transfer complexes

Polymer charge-transfer complexes

A novel charge-transfer polymer for separating hydrocarbon fractions of crude oils

Hydrocarbon fractions in crude oil were separated by a new charge-transfer polymer in place of silver ions in Argentation TLC. The charge-transfer plates are cheaper than their silver nitrate equivalents, do not discolour, and store well. The polymer/silica gel mix can be re-used.

Charge-transfer polymers containing 7,7,8,8-tetracyanoquinodimethan and tetrathiafulvalene

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharge-transfer polymers containing 7,7,8,8-tetracyanoquinodimethan and tetrathiafulvaleneW. R. HertlerCite this: J. Org. Chem. 1976, 41, 8, 1412–1416Publication Date (Print):April 1, 1976Publication History Published online1 May 2002Published inissue 1 April 1976https://doi.org/10.1021/jo00870a027RIGHTS & PERMISSIONSArticle Views329Altmetric-Citations59LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (692 KB) Get e-Alerts Get e-Alerts

Photoinduced decay of surface charge in polymer‐charge transfer complex systems

Journal of Polymer Science: Polymer Letters EditionVolume 13, Issue 3 p. 141-152 Article Photoinduced decay of surface charge in polymer-charge transfer complex systems M. Kryszewski, M. Kryszewski Polymer Institute, Technical University, Lódź, PolandSearch for more papers by this authorP. Wojciechowski, P. Wojciechowski Polymer Institute, Technical University, Lódź, PolandSearch for more papers by this authorS. Sapieha, S. Sapieha Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this authorM. Zieliński, M. Zieliński Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this authorJ. Tyczkowski, J. Tyczkowski Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this author M. Kryszewski, M. Kryszewski Polymer Institute, Technical University, Lódź, PolandSearch for more papers by this authorP. Wojciechowski, P. Wojciechowski Polymer Institute, Technical University, Lódź, PolandSearch for more papers by this authorS. Sapieha, S. Sapieha Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this authorM. Zieliński, M. Zieliński Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this authorJ. Tyczkowski, J. Tyczkowski Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Lódź, PolandSearch for more papers by this author First published: March 1975 https://doi.org/10.1002/pol.1975.130130305Citations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume13, Issue3March 1975Pages 141-152 RelatedInformation