384 results on '"V. V. Kudryavtsev"'
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2. Comparative characteristics of products of processing of fusible copoly (urethane-imides) from the solutions and melts formed by them
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A. L. Didenko, A. G. Ivanov, V. E. Smirnova, G. V. Vaganov, E. N. Popova, D. A. Kuznetsov, L. A. Myagkova, V. M. Svetlichniy, V. E. Yudin, and V. V. Kudryavtsev
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Polymers and Plastics ,Chemical Engineering (miscellaneous) - Abstract
Self-supporting films and thick-walled moldings (blades) were obtained from solutions and melts of multiblock (segmental) copoly(urethane-imides). The initial copoly(urethane-imides) were obtained on the basis of aliphatic polyesters: poly(propyleneglycol), poly(diethyleneglycoladipinate) and polycaprolactone, dianhydride of 1,3-bis(3’,4-dicarboxyphenoxy) benzene and aromatic diamines: 4,4’-bis-(4”-aminophenoxy)biphenyl and 1,4-bis(4’-aminophenoxy)diphenylsulfone. Samples of films and moldings were studied by IR spectroscopy, TGA, DSC and mechanical analysis under static and dynamic (DMA) experimental conditions. It is assumed that the diff erences in the properties of films and moldings are due to an increase in the proportion of aromatic blocks due to microdestruction of polymer chains and increased interfacial interactions of polyester and urethanimide microphases (blocks) in polymer systems during the processing of polymers from the melt by injection molding.
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- 2022
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3. Synthesis and properties of aromatic polyimides chemically modified by polyurethanes
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A. L. Didenko, D. A. Kuznetsov, A. G. Ivanov, V. E. Smirnova, G. V. Vaganov, A. M. Kamalov, V. M. Svetlichnyi, V. E. Yudin, and V. V. Kudryavtsev
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General Chemistry - Published
- 2022
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4. Synthesis and dynamic mechanical properties of cross-linked multiblock poly(urethane-imide) copolymers
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G. V. Vaganov, Vladimir E. Yudin, I. A. Kobykhno, Oleg V. Tolochko, V. E. Smirnova, Elena N. Popova, E. S. Vasiliyeva, E. A. Bogdanova, Dmitry A. Kuznetsov, V. M. Svetlichniy, A. L. Didenko, A. G. Ivanov, and V. V. Kudryavtsev
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chemistry.chemical_classification ,chemistry.chemical_compound ,Thermogravimetric analysis ,Differential scanning calorimetry ,chemistry ,Diphenyl sulfone ,Polymer chemistry ,Copolymer ,General Chemistry ,Polymer ,Dynamic mechanical analysis ,Imide ,Isocyanate - Abstract
Poly(urethane-imide) copolymers (PUICs) containing reactive carboxyl groups in hard imide segment were synthesized from poly(propylene glycol) with isocyanate end groups, 1,3-bis(3′,4′-dicarboxyphenoxy)benzene dianhydride, aromatic diamines 4,4′-bis(4″-aminophenoxy)diphenyl sulfone or 4,4′-bis-(4″-aminophenoxy)biphenyl, and 3,5-diaminobenzoic acid. The PUICs were covalently cross-linked using reactions of carboxyl groups with aromatic diisocyanates and 1,2,5,6-diepoxycyclooctane. The polymers obtained were studied by thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. It was shown that the structure of the cross-linking agents influences the properties of cross-linked PUICs. Changes in the mechanical loss factor (tg δ) were analyzed vs. chemical structure of the PUICs. The maximum tg δ values of the copolymers studied are in the range of 0.3–0.4, which suggests good damping capacity of these systems.
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- 2021
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5. Synthesis, Heat Resistance, and Mechanical Properties of Cross-Linked Urethane–Imide Copolymers Containing Blocks of Two Structurally Different Aliphatic Fragments (Polyether and Polyester) in the Backbone
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A. L. Didenko, A. G. Ivanov, E. A. Bogdanova, V. E. Smirnova, G. V. Vaganov, E. N. Popova, D. A. Kuznetsov, I. A. Kobykhno, E. S. Vasil’eva, O. V. Tolochko, V. M. Svetlichnyi, V. E. Yudin, and V. V. Kudryavtsev
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General Chemical Engineering ,General Chemistry - Published
- 2021
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6. Investigation of the Effect of Mono- and Diurethane Units on the Deformation and Strength Properties of Polyurethanimides
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V. V. Kudryavtsev, D. A. Kuznetsov, G. V. Vaganov, V. Yu. Elokhovskii, A. L. Didenko, V. M. Svetlichnyi, and Vladimir E. Yudin
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Chemistry ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Proton magnetic resonance ,0104 chemical sciences ,DIETHYLENE GLYCOL ADIPATE ,Polymer chemistry ,Mole ,Elasticity (economics) ,Deformation (engineering) ,0210 nano-technology - Abstract
The effect of synthesis conditions for macrodiisocyanate (temperature, reaction duration, ratio of components) based on poly(diethylene glycol adipate) (Mn = 2.5 × 103) and 2,4-toluene diisocyanate on the composition of the reaction products has been studied. The number of mono- and diurethane units was estimated using proton magnetic resonance spectra. It was found that carrying out the synthesis at 80°C using an eight-fold excess of 2,4-toluene diisocyanate results in the production of a macrodiisocyanate with a diurethane unit content of less than 1 mol %. Based on the isolated macrodiisocyanate, a fusible polyurethanimide, superior in elasticity to the unmodified analogue, was prepared.
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- 2020
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7. The Thermal Stability and Mechanical Properties of Non-Segregating Blends of Polyimides with Copoly(Urethane-Imide)s
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V. V. Kudryavtsev, Alexey Ivanov, Danila Kuznetcov, G. V. Vaganov, Boris Chernitsa, V. E. Smirnova, A. L. Didenko, Valentin M. Svetlichnyi, Elena Popova, and Vladimir E. Yudin
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Thermogravimetric analysis ,Materials science ,Mechanical Engineering ,02 engineering and technology ,Dynamic mechanical analysis ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Differential scanning calorimetry ,chemistry ,Mechanics of Materials ,General Materials Science ,Thermal stability ,Thermoplastic elastomer ,Composite material ,0210 nano-technology ,Imide ,Polyimide - Abstract
The series of compositions containing thermodynamically incompatible flexible blocks of aliphatic polyesters and rigid blocks of aromatic bis (urethane) imides in the volume of polymers was obtained on the basis of multiblock (segmented) poly (urethane-imides) and related aromatic polyimides. The series includes segmented poly (urethane-imides) with different relative content of flexible and rigid blocks, non-segregating mixtures of poly (urethane-imides) and thermoplastic partially crystalline polyimide, statistical copolymers of poly (urethane-imide) with imide, and non-segregating mixtures of statistical copolymers with thermoplastic polyimide. The derived polymer systems were studied using thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. The deformation and strength properties of film samples are determined. It is shown that the properties of the studied polymers change as their content of imides blocks increases, and the transition from thermoplastic poly (urethane-imide) elastomers to thermoplastic polyimides is observed.
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- 2020
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8. Multiblock Copoly(urethane–imide)s with the Properties of Thermoplastic Elastomers
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V. V. Kudryavtsev, V. E. Smirnova, D. A. Kuznetsov, G. V. Vaganov, V. M. Svetlichnyi, A. G. Ivanov, Vladimir E. Yudin, A. L. Didenko, and Elena N. Popova
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chemistry.chemical_classification ,Materials science ,Thermoplastic ,Polymers and Plastics ,Polymer science ,Chemical structure ,02 engineering and technology ,General Chemistry ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Macromolecular Compounds ,01 natural sciences ,0104 chemical sciences ,Polyester ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Thermoplastic elastomer ,0210 nano-technology ,Imide - Abstract
A review of the works performed at the Institute of Macromolecular Compounds, Russian Academy of Sciences in the field of multiblock copoly(urethane–imide)s, a relatively new subclass of thermally stable polymers, is presented. The synthesis of the representative family of copoly(urethane–imide)s different in the chemical structure and ratio of flexible polyester/polyether and rigid urethane–imide blocks is performed. Mixed compounds composed of synthesized copoly(urethane–imide)s and thermoplastic polyimides are obtained. The effect of the chemical structure of the flexible and rigid blocks and their ratio on the glass and melting transitions of the studied polymer systems is investigated. Polymer systems that form stable melts and are suitable for processing to thick-wall products, thermoplastic elastomers, are proposed.
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- 2020
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9. Co-poly(urethane-imide)s based on poly[di(ethylene glycol) adipate] and their compositions with thermoplastic polyimide: synthesis and properties
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Danila Kuznetcov, G. V. Vaganov, V. V. Kudryavtsev, V. E. Smirnova, A. G. Ivanov, Elena N. Popova, A. L. Didenko, V. M. Svetlichnyi, and Vladimir E. Yudin
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010405 organic chemistry ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Diamine ,Adipate ,Polymer chemistry ,Copolymer ,Glass transition ,Benzene ,Imide ,Ethylene glycol ,Polyimide - Abstract
Based on poly[di(ethylene glycol) adipate] (Mn = 2500) terminated by 2,4-toluene diiso-cyanate (TDI), bis(3´,4-dicarboxyphenoxy)benzene (dianhydride R), and 1,4-bis(4´-amino-phenoxy)biphenyl (diamine ODFO) a number of co-poly(urethane-imide) samples with the general formula (R-TDI-2500-TDI-R)(ODFO)n (n = 1–3, 5), differing in the content of aromatic blocks (from 37 to 65 wt.%) were obtained. The synthesized samples were characterized by the TGA, DSC, and DMA methods and were used to prepare mixed compositions with the known R-ODFO polyimide in two versions, namely, with a polyimide content of 10 and 90 wt.%. Mixed compositions were investigated by DSC. The effect of an increase in the relative content of imide units on the glass transition and melting temperatures of the crystalline phase of copolymers and mixed compositions is detected.
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- 2020
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10. Heat Resistance and Dynamic Mechanical and Rheological Properties of a Blend of Crystallizing Polymers, Polyimide and Copoly(urethane—imide), at Identical Chemical Structure of the Imide Blocks in the Initial Polymers
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V. E. Smirnova, V. V. Kudryavtsev, V. Yu. Elokhovskii, G. V. Vaganov, A. G. Ivanov, Elena N. Popova, Vladimir E. Yudin, V. M. Svetlichnyi, A. L. Didenko, and D. A. Kuznetсov
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chemistry.chemical_classification ,Thermogravimetric analysis ,Chemistry ,General Chemical Engineering ,02 engineering and technology ,General Chemistry ,Dynamic mechanical analysis ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Polyester ,Differential scanning calorimetry ,Chemical engineering ,law ,Phase (matter) ,Crystallization ,0210 nano-technology ,Polyimide - Abstract
A blend of crystallizing polyimide and newly synthesized partially crystalline multiblock (segmented) copoly(urethane—imide), consisting of 75 wt % copoly(urethane—imide) and 25 wt % polyimide, was prepared and studied by thermal gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, and melt rheology. Blend samples were prepared by mixing copoly(urethane—imide) and polyimide prepolymers in an N-methyl-2-pyrrolidone solution, in which the subsequent thermal or chemical imidization of the system components was performed. The properties of the initial polyimide, copoly(urethane—imide), and the blend were compared. The results of studies by differential scanning calorimetry and dynamic mechanical analysis demonstrate the presence of a crystalline soft polyester phase in the copoly(urethane—imide) structure and of the crystalline hard imide phase in the blend structure, which suggests the crystallization suppression in samples of the blend. The dynamic viscosity of the melt of chemically imidized copoly(urethane—imide) and blend samples is lower than that of their thermally imidized analogs. Dynamic mechanical analysis shows that the initial copoly(urethane—imide) behaves as a thermoelastoplastic. The blends consisting of copoly(urethane—imide) and thermoplastic polyimide are similar in properties to polyimide thermoplastics for structural purposes.
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- 2020
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11. Investigation by TGA, DSC and DMA Urethane-Imide Copolymers with High Content of Hard Imide Blocks
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V. E. Smirnova, V. V. Kudryavtsev, Elena Popova, Tatyana A. Kuznetsova, Ekaterina Kuzmenko, A. L. Didenko, Alexey Ivanov, and G. V. Vaganov
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010302 applied physics ,chemistry.chemical_classification ,Thermoplastic ,Materials science ,Mechanical Engineering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Mechanics of Materials ,0103 physical sciences ,Copolymer ,General Materials Science ,0210 nano-technology ,Imide ,Polyimide - Abstract
Poly (diethylene glycol) adipate diol, tolylene-2,4-diisocyanate, 1,3-bis (3',4-dicarboxylphenoxy) benzene and 1,4-bis (4'-aminophenoxy) biphenyl were used as monomers to form statistical copoly (urethane-imide) s with variable content of imide blocks (from 37 to 65% (wt)). The copolymers imide blocks on the Tg and Tm values relative content increasing effect was traced, which is associated with the phase separation of hard imide and flexible polyester blocks in the systems studied.
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- 2019
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12. Dynamic mechanical properties, thermal and heat resistance of multiblock co-poly(urethane-imide) films with graphene and tungsten disulfide
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A. L. Didenko, Vladimir E. Yudin, V. M. Svetlichnyi, Elena N. Popova, V. V. Kudryavtsev, Oleg V. Tolochko, G. V. Vaganov, Danila Kuznetcov, Ekaterina Vasilyeva, and V. E. Smirnova
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chemistry.chemical_classification ,Thermogravimetric analysis ,Condensation polymer ,010405 organic chemistry ,Diphenyl sulfone ,Tungsten disulfide ,General Chemistry ,Polymer ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Polyester ,chemistry.chemical_compound ,Polypropylene glycol ,chemistry ,Chemical engineering ,Adipate - Abstract
Organic-inorganic composites filled with nanoscale graphene and tungsten disulfide particles using thermoelastoplastic multiblock co-poly(urethane-imide)s as polymer matrices were obtained. The matrix polymers were the products of the polycondensation of 1,3-bis-(3′,4-dicarboxyphenoxy)benzene dianhydride, 1,4-bis(aminophenoxy)diphenyl sulfone, and two aliphatic polyesters terminated by 2,4-toluene diisocyanate, namely, polypropylene glycol (Mn = 2300) and poly(ethylene adipate) (Mn = 2700). The weight fraction of aromatic segments in samples of co-poly(urethane-imide)s differed by a factor of two. Obtained composites were investigated by TGA, DSC, and DMA methods.
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- 2019
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13. Formation of Highly Conducting Optically Transparent Films with Multigraphene Structure via Carbonization of Polyimide Langmuir–Blodgett Films
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S. I. Goloudina, Alexander N. Smirnov, G. A. Konoplev, V. M. Pasyuta, V. V. Kudryavtsev, V. V. Andryushkin, Iosif V. Gofman, Demid A. Kirilenko, V. P. Sklizkova, V. M. Svetlichnyi, E. N. Sevost’yanov, and V. V. Luchinin
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010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,Carbonization ,business.industry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Langmuir–Blodgett film ,symbols.namesake ,Transmission electron microscopy ,0103 physical sciences ,symbols ,Transmittance ,Optoelectronics ,Graphite ,0210 nano-technology ,business ,Raman spectroscopy ,Polyimide ,Sheet resistance - Abstract
Multigraphene films have been for the first time obtained on the surface of quartz glass via carbonization of polyimide Langmuir–Blodgett films. The Raman spectra of the films show bands G and D and a broad band at 2300–3200 cm–1, which are characteristic of graphite-like films. The transmission electron microscopy demonstrated that the films are constituted by “stacks” of layers spaced by 0.36 nm. The surface resistance of the 5-nm-thick films was 1.2 ± 0.2 kΩ, and the transmittance was 87% at λ = 550 nm. The transmittance was 97% in the IR part of the spectrum and 70–80% in the UV part.
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- 2019
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14. Effect of Hard Segment Structure on the Thermomechanical Properties of Polyurethaneimides
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V. E. Smirnova, V. V. Kudryavtsev, Elena N. Popova, Vladimir E. Yudin, A. L. Didenko, D. A. Kuznetsov, G. V. Vaganov, and V. M. Svetlichnyi
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Substituent ,02 engineering and technology ,Nuclear magnetic resonance spectroscopy ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Diamine ,Adipate ,Polymer chemistry ,Materials Chemistry ,Copolymer ,0210 nano-technology ,Segment structure ,Ethylene glycol - Abstract
New segmented polyurethaneimides containing poly(ethylene glycol adipate) soft segments and bis(urethaneimide) hard segments are synthesized. Copolymers are obtained on the basis of poly(ethylene glycol adipate) (Mn = 2.5 × 103) terminated with 2,4-toluene diisocyanate, two aromatic dianhydrides, and six aromatic diamines. The structure of the synthesized polymers is studied by IR and NMR spectroscopy. The thermal properties of the copolymers are characterized by TGA and DSC. Effects of hard segment length and substituent position in the diamine fragment on the thermal and mechanical properties of the polyurethaneimides are investigated.
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- 2019
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15. Polyimide Synthesis by Chemical Cyclization of Polyamic Acids
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V. V. Kudryavtsev
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Materials science ,Polymer chemistry ,Polyimide - Published
- 2020
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16. Phase Separation in Mixed Compositions Containing Crystallizable Copoly(Uretane-Imide) and Crystallizable Polyimide
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Didenko, A. L., V. E. Smirnova, E. N. Popova, G. V. Vaganov, D. A. Kuznetcov, A. G. Ivanov, V. M. Svetlichnyi, V. E. Yudin, and V. V. Kudryavtsev
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polymer mixture ,TGA ,MTA ,rubber-like elasticity ,copoly(urethane-imide) ,melt rheology ,thermoplastic ,phase separation ,polyimide ,DSC - Abstract
A number of samples of copoly(urethane)imides of CPUI (R-TDI-2500-TDI-R)(BAPB)n(n=1,2,3,5) based on poly(diethylene glycol)adipinate (Mn=2500) (2500), bis(3',4-dicarboxyphenoxy)benzene(Rdianhydride)and 1,4-bis terminated with 2,4-toluylenediisocyanate (TDI) were synthesized(4'-aminophenoxy)biphenyl (diamine BAPB).CPUI differ in the content of aromatic blocks in the polymer from 37 to 65% (wt of mass).The synthesized samples were characterized by TGA, DSC and MTA methods. CPUI were used to prepare mixed compositions together with polyimide (R-BAPB).The compositions were synthesized in two versions: a) - 10% (wt) and b)-90% (wt), polyimide, respectively. The mixed compositions were investigated using the DSC method. We described the effect of increasing the content of imide links on the values of Tm and Tg copolymers and mixed compositions. This effect is due to the separation and interaction of aromatic (imide) and aliphatic (polyester) phases. Keywords: copoly(urethane-imide), polyimide, polymer mixture, thermoplastic, thermoplastic, TGA, DSC, MTA, melt rheology, phase separation, rubber-like elasticity.
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- 2020
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17. Synthesis and Properties of New 2,6-Poly(phenylquinoline)s and Their Composites with 2,1,3-Benzothiadiazole
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V. M. Svetlichnyi, M. E. Vylegzhanina, Elena N. Popova, A. Ya. Volkov, V. V. Kudryavtsev, N. V. Matyushina, Tatiana Sukhanova, Iosif V. Gofman, L. A. Myagkova, and E. L. Aleksandrova
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chemistry.chemical_classification ,Polymers and Plastics ,Carbazole ,Quinoline ,Composite number ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Photosensitivity ,Materials Chemistry ,Ceramics and Composites ,Side chain ,lipids (amino acids, peptides, and proteins) ,Composite material ,0210 nano-technology ,Alkyl - Abstract
We synthesized 2,6-poly(phenylquinoline)s, the elementary polymer unit of which contained alkyl carbazole or alkyl indolo[3,2-b]carbazole moieties with C12 and C18 alkyl side chains at nitrogen atoms and the oxygen or phenylamine bridge group between the quinoline cycles. The synthesized polymers form heat-resistant coatings, for which the temperature for 5% weight loss is higher than 450°С. It is demonstrated that introduction of 10 wt % of 2,1,3-benzothiadiazole to the poly(phenylquinoline)s leads to an increase in the photosensitivity of the composite as compared with the original polymers. Structural-morphological studies of the synthesized poly(phenylquinoline)s and their composites were carried out.
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- 2017
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18. Crops cultivation parameters application in the land misuse assessment
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K A Zhichkin, G T Allen, L N Zhichkina, Vladimir Nosov, and V V Kudryavtsev
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Agroforestry ,Environmental science - Abstract
The article discusses the problems of determining the agricultural crops parameters application for calculating the amount which paying compensation in the inappropriate agricultural land occupation case on the growing open ground tomatoes example. The study purpose is to determine the compensation amount in agricultural land misuse case using the open ground tomatoes example. At the same time, the following tasks were solved: - to determine the typical technology for growing open ground tomatoes in the Samara region; - on the basis of statistical data calculate the profitable part of growing open ground tomatoes; - identify the costs main sources and calculate the expenditure amount; - to determine the compensation amount in the case of growing open ground tomatoes with land alternative use in the Samara region.
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- 2021
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19. Forest fires and forestry firefighting organization
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I.A. Abdulragimov, L N Zhichkina, V V Kudryavtsev, P S Burlankov, Vladimir Nosov, and K A Zhichkin
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Geography ,Work (electrical) ,Econometric methods ,Firefighting ,Forestry ,Samara ,Fire hazard - Abstract
The article discusses the situation with forest fires in the Samara region and suggests measures to combat them. The purpose of the work is to analyze the occurrence of fires in the Samara region, including in the Kinel-Cherkasy forestry. The study intends to solve the following problems: - to study the dynamics and causes of forest fires in the Samara region and the Kinel-Cherkasy forestry; - determine the extent of damage caused to the region forests by fires; - to analyze measures to improve the fire situation. Research methods: the abstract-logical method was used to assess the general situation with forest fires in the forestry of the Samara region; situational and system analyzes, econometric methods and the method of expert evaluations - to determine measures to improve the fire situation. Forest fires have a significant impact on the situation with the forests in the region. If in 2017 the share of forests killed by fires was less than 10%, then in 2010 and 2018 - more than 94%. In absolute terms, the minimum in 2018 was 68.8 ha, the maximum was 1687 ha (2010), which amounted to 0.25% of the region total forest area. It is necessary to carry out fire and preventive measures, taking into account the fire hazard situation in the area and the anthropogenic load on forests and adjacent territories. Based on the analyzed data, it is necessary to ensure the conservation of adult forest plantations and unclosed forest crops, taking into account the use of neighboring territories by farms and enterprises.
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- 2021
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20. Composite coatings based on A–OOO polyimide and WS2 nanoparticles with enhanced dry sliding characteristics
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A. G. Kolmakov, V. V. Kudryavtsev, N. E. Starikov, A. D. Breki, Oleg V. Tolochko, D. A. Provotorov, A. E. Gvozdev, Yu. A. Fadin, A. L. Didenko, E. S. Vasilyeva, and N. N. Sergeyev
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010302 applied physics ,Materials science ,Dry friction ,Composite number ,Tungsten disulfide ,General Engineering ,Nanoparticle ,02 engineering and technology ,Tribology ,021001 nanoscience & nanotechnology ,01 natural sciences ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,General Materials Science ,Composite material ,0210 nano-technology ,Polyimide - Abstract
One- and two-step syntheses of composite coatings with an A–OOO polyimide matrix filled with 40-nm tungsten disulfide nanoparticles produced using gas-phase synthesis, which are intended for operation under dry friction conditions, are described. Results of studying the tribological behavior of these coatings are presented.
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- 2017
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21. Effect of Meta- and Para-Substitution of the Aromatic Diamines on the Properties of Poly(Amidoimidourethane)
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Danila Kuznetcov, Ilya Kobykhno, V. V. Kudryavtsev, Andrei L. Didenko, Alexey Ivanov, Ekaterina Vasilyeva, G. V. Vaganov, and Oleg V. Tolochko
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chemistry.chemical_classification ,Thermogravimetric analysis ,Materials science ,Mechanical Engineering ,02 engineering and technology ,Polymer ,Nanoindentation ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Differential scanning calorimetry ,chemistry ,Mechanics of Materials ,Diamine ,Polymer chemistry ,Copolymer ,General Materials Science ,0210 nano-technology ,Thermal analysis ,Tensile testing - Abstract
The paper experimentally studies the effect of meta and para- substitution of the amino groups in the diamine used in the synthesis of multiblock copolymers. The way for synthesis of new multiblock copolymers with the possibility of replacing the diamine in the polymer structure was shown. Thermal and mechanical properties of synthesized copolymers had been characterized by means of differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis and by nanoindentation and tensile test.
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- 2016
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22. Dielectric relaxation in segmented copolyurethane imides
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V. V. Kudryavtsev, René Castro, N. A. Nikonorova, and Andrei L. Didenko
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Materials science ,Polybutylene ,02 engineering and technology ,Dielectric ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Dipole ,Crystallography ,chemistry ,Adipate ,Phase (matter) ,Polymer chemistry ,Materials Chemistry ,Ceramics and Composites ,Relaxation (physics) ,0210 nano-technology ,Glass transition ,Imide - Abstract
The dielectric relaxation and molecular mobility of multiblock segmented copolyurethane imides based on pyromellitic anhydride and aromatic diamines and 2.4-methylene diisocianate (forms a rigid urethane imide segment) terminated polybutylene adipate (Mn 2700) (forms a soft segment) were studied by the dielectric method. It was found several dipole relaxation processes, local γ and β (in the glassy state) and cooperative α1 and α related to the soft and rigid phase, respectively (in the rubbery state). Beside this, Maxwell Wagner Sillars (MWS) process associated with interfacial polarization was observed. The presence of α, α1, and MWS processes is a reliable indication of the microphase separation in the studied systems.
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- 2016
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23. Synthesis and tribotechnical properties of composite coatings with PM–DADPE polyimide matrix and fillers of tungsten dichalcogenide nanoparticles upon dry sliding friction
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A. G. Kolmakov, V. V. Kudryavtsev, D. A. Provotorov, N. E. Starikov, A. E. Gvozdev, E. S. Vasilyeva, N. N. Sergeyev, Oleg V. Tolochko, A. D. Breki, Yu. A. Fadin, and A. L. Didenko
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010302 applied physics ,Materials science ,Composite number ,Tungsten disulfide ,General Engineering ,chemistry.chemical_element ,Nanoparticle ,02 engineering and technology ,Tungsten ,Tribology ,021001 nanoscience & nanotechnology ,01 natural sciences ,chemistry.chemical_compound ,chemistry ,0103 physical sciences ,Tungsten diselenide ,General Materials Science ,Composite material ,0210 nano-technology ,Dry lubricant ,Polyimide - Abstract
A synthesis is described and tribological characteristics are presented for composite coatings 40 μm thick with a PM–DADPE polyimide matrix and a filler of tungsten disulfide nanoparticles with size of 4 nm and tungsten diselenide nanoparticles 60 × 5 nm in size obtained via gas-phase synthesis.
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- 2016
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24. Basic principles of tourist services market segmentation
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E. V. Logvina, V. V. Kudryavtsev, T. V. Gaifutdinova, A. G. Redkin, Y. N. Shol, and Natalia E. Goryushkina
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Service (business) ,Knowledge management ,Computer science ,business.industry ,media_common.quotation_subject ,05 social sciences ,Tourism -- Case studies ,Consumers -- Attitudes ,010501 environmental sciences ,01 natural sciences ,General Business, Management and Accounting ,Identification (information) ,Supply and demand -- Case studies ,Market segmentation ,Originality ,0502 economics and business ,Segmentation ,Product (category theory) ,business ,General Economics, Econometrics and Finance ,Psychographic ,050203 business & management ,Tourism ,0105 earth and related environmental sciences ,media_common - Abstract
Purpose: The main aim of the article is to identify the principles of tourist services for an effective segmentation using data from official primary and secondary bases. Design/Methodology/Approach: The authors have justified the importance of dividing potential tourists into homogenous groups (segments) in accordance with the general characteristic features of their demand. In that manner, according to the authors, a tourist product is provided with its target orientation as, on the one hand, it cannot meet the requirements of all tourists and on the other hand, a tourist company can concentrate their marketing efforts on the most perspective market segments rather than dissipate them. Findings: A definition of 'tourist service' has been made and its characteristic features have been described as well. Stages of segmenting starting from selection of criteria to determination of methods of work with the chosen segment have been identified and described. Practical implications: Identification of segments in tourism is mainly made based on their geographical, demographical, socio-economic, psychographic, behavior characteristics or their combinations. On the other hand, the authors stress on the fact that there is no universal segmentation approach and therefore, potential tourists can be classified based on other characteristics. Originality/Value: The conclusion that successful segmenting determines efficient operation of a tourist enterprise has been made., peer-reviewed
- Published
- 2019
25. Satellite monitoring systems in forestry
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V V Kudryavtsev, Vyacheslav Zhenzhebir, L N Zhichkina, H T Aydinov, K A Zhichkin, and Vladimir Nosov
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History ,Space technology ,business.industry ,Computer science ,Monitoring system ,Forestry ,Earth remote sensing ,Space (commercial competition) ,Felling ,Computer Science Applications ,Education ,Software ,Work (electrical) ,Satellite ,business - Abstract
Space technologies in Earth remote sensing are among the most relevant technologies for monitoring forestry. Difficulties of controlling tree felling and other activities by forestry employees constitute an objective problem which can only be solved by application of space monitoring instruments. The article shows that using the LandViewer Software would provide regional forestry a wealth of information needed for ongoing work and detection of violations. The considered examples demonstrate that space monitoring provides a more accurate determination of the size of forest blocks and the felling volume.
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- 2020
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26. Composites of multiblock (segmented) aliphatic poly(ester imide) with zirconia nanoparticles: Synthesis, mechanical properties, and pervaporation behavior
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V. E. Smirnova, V. V. Kudryavtsev, Elena N. Popova, Roman V. Kremnev, A. L. Didenko, S. V. Kononova, Iosif V. Gofman, Vladimir E. Yudin, A. N. Bugrov, and V. M. Svetlichnyi
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Pyromellitic dianhydride ,Nanocomposite ,Materials science ,Polymers and Plastics ,Diol ,chemistry.chemical_compound ,chemistry ,Adipate ,Polymer chemistry ,Materials Chemistry ,Ceramics and Composites ,Pervaporation ,Composite material ,Imide ,Prepolymer ,Yttria-stabilized zirconia - Abstract
On the basis of pyromellitic dianhydride, p-phenylenediamine, and poly(butylene adipate) diol (M n = 1 × 103) and poly(ethylene adipate) diol (M n = 1 × 104) taken at a molar ratio of 10 : 1, initial samples of multiblock poly(ester imide) and its composites with nanoparticles of two types—zirconia ZrO2 surface-treated with γ-aminopropyltriethoxysilane and zirconia doped with yttria (Y0.03Zr0.97O1.985)—are synthesized. Nanoparticles are introduced into the polymer matrix at the stage of synthesis of the poly(ester imide) prepolymer. The mechanical properties of films of poly(ester imide) and its nanocomposites are determined under static and dynamic testing conditions, and the permeabilities and separation selectivities of corresponding solid films for mixtures of aromatic and aliphatic hydrocarbons (toluene-n-octane and benzenecyclohexane) of various compositions are measured under pervaporation testing conditions. It is shown that the different mechanical and pervaporation properties of film samples are due to the presence of zirconiabased nanoparticles.
- Published
- 2014
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27. Sensitization of the photoelectric effect in carbazole- and indolocarbazole-containing poly(phenylquinoline)s by benzothiadiazole acceptor molecules
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L. A. Myagkova, V. V. Kudryavtsev, Alexey R. Tameev, N. V. Matyushina, E. L. Aleksandrova, and V. M. Svetlichnyi
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chemistry.chemical_classification ,Photocurrent ,Chemistry ,Carbazole ,Polymer ,Photoelectric effect ,Condensed Matter Physics ,Indolocarbazole ,Photochemistry ,Acceptor ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Photosensitivity ,Molecule - Abstract
The efficient sensitization of the photoelectric effect in mixed compositions of poly(phenylquinoline)s (PPQ) with 2,1,3-benzothiadiazole (BTDZ) molecules is established. The introduction of 10 wt % BTDZ results in extension of the spectral sensitivity range of PPQ and an increase in the photosensitivity and photocurrent by factors of 4.5 and more than 6, respectively. It is shown that the effect is caused by complex formation between PPQ donor fragments and BTDZ acceptor molecules; the strongest, in comparison with the increase in photosensitivity, is probably caused by the transport of free photogenerated carriers (electrons) over sensitizer molecules introduced into the polymer.
- Published
- 2014
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28. Effect of the structural organization of polyamic-acid salt solutions on the morphology of Langmuir Monolayers of the prepolymer
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V. P. Sklizkova, N. D. Stepina, Radmir V. Gainutdinov, A. L. Tolstikhina, N. A. Kalinina, and V. V. Kudryavtsev
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Solvent ,Langmuir ,Materials science ,Chemical engineering ,Scattering ,Amphiphile ,Monolayer ,Polymer chemistry ,Thin film ,Prepolymer ,Polyimide ,Surfaces, Coatings and Films - Abstract
The structure of Langmuir-Blodgett (LB) films formed from solutions of comblike N,N-dimethylhexadecylammonium polyamic-acid salt on the basis of the dianhydride of 3,3′,4,4′-diphenyl-tetracarboxylic acid and o-tolidine is studied by the AFM method. The structural organization of dilute solutions of the amphiphilic polyimide prepolymer in mixed solvents (DMAA-dioxane, DMAA-benzene, and MP-benzene) is studied by the method of polarized light scattering. The statistical structural parameters of the solutions are calculated using Debye-Stein theory. It is shown that the dimensions of ordered scattering formations depend on the chemical nature of the mixed solvent components. The parameters, characterizing the structure of the prepolymer solutions in various solvents, are compared. The dependence of the surface morphology of the LB films on the structural organization of the initial prepolymer solutions is revealed.
- Published
- 2013
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- View/download PDF
29. Copolymers of carbazole- and indolocarbazole-containing phenylquinolines as new materials for electroluminescent devices
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R. Yu. Smyslov, Vladimir D. Pautov, V. V. Kudryavtsev, N. V. Matyushina, T. N. Nekrasova, Alexey R. Tameev, L. A. Myagkova, V. M. Svetlichnyi, and E. L. Aleksandrova
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Materials science ,Carbazole ,Quinoline ,New materials ,Electroluminescence ,Condensed Matter Physics ,Indolocarbazole ,Photochemistry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Bridging oxygen ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Copolymer ,Luminescence - Abstract
The photophysical and electrical properties of copolymers based on 2,6-polyphenylquinolines containing a bridging oxygen or phenylamine group between quinoline rings and octyl- or dodecylcarbazole or dioctylindolo[3,2-b]carbazole fragments in the aromatic radical are studied. It is shown that the introduction of carbazole and indolo[3,2-b]carbazole fragments emitting in the visible spectral range into the aromatic radical of a copolymer makes it possible to obtain white luminescence. The intensity of this luminescence exceeds, for copolymers in a photoinert matrix, that of the initial homopolymers. This circumstance, combined with rather high carrier mobilities on the order of 5 × 10−6 cm2 V−1 s−1, makes the copolymers promising for the development of electroluminescent devices on their basis.
- Published
- 2013
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30. Dynamic mechanical analysis of multiblock (segmental) polyesterimides
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V. E. Smirnova, V. V. Kudryavtsev, A. V. Zarbuev, V. M. Svetlichnyi, Elena N. Popova, Iosif V. Gofman, A. L. Didenko, and Vladimir E. Yudin
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Chemistry ,General Chemical Engineering ,Adipate ,Thermal ,Polymer chemistry ,Modulus ,General Chemistry ,Dynamic mechanical analysis ,Composite material ,Glass transition ,Dynamic elastic modulus - Abstract
Thermal, deformation-strength, and dynamic mechanical properties of films of segmental polyesterimides prepared from pyromellitic anhydride, aromatic diamines, and poly(butylene adipate) (M n = 1000) with hydroxy terminal groups were studied. The glass transition points T g of the samples obtained are below 0°C. The dynamic elastic modulus curves at temperatures higher than T g are characterized by a portion in which the modulus only weakly depends on temperature.
- Published
- 2013
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31. Spectroscopic study of polyphenylquinolines—materials with efficient intramolecular charge transfer
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Anatoly V. Vannikov, R. Yu. Smyslov, L. A. Myagkova, N. V. Matyushina, E. L. Aleksandrova, V. M. Svetlichnyi, T. N. Nekrasova, Alexey R. Tameev, Vladimir D. Pautov, and V. V. Kudryavtsev
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chemistry.chemical_compound ,Absorption spectroscopy ,chemistry ,Carbazole ,Intramolecular force ,Polymer chemistry ,Arylene ,Quinoline ,Nitro ,Alkylation ,Acceptor ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Abstract
The energy structure and nature of intramolecular charge transfer have been determined for a series of synthesized 2,6-polyphenylquinolines (PPQs) containing resorcinol, oxygen, and phenylamine bridging groups between phenylquinoline cycles and possessing an arylene radical in the form of alkylated derivatives of carbazole or indolo[3,2-b]carbazole, as well as arylated derivatives of carbazole with nitro- and fluorine substituents. The analysis was based on data on their absorption spectra, photosensitivity, carrier photogeneration quantum efficiency, and luminescence. It is shown that the PPQ monomeric unit is a composite intramolecular charge-transfer complex (ICTC) between the donor arylene fragment and the acceptor quinoline cycle; the latter, in turn, is an ICTC between the donor bridging group and quinoline ring (when acceptor fluorine or nitro substituents are introduced into the carbazole structure, the complex becomes ternary), and the narrowest band gap (2.3 eV) corresponds to the PPQ having a phenylamine bridging group and a fragment of indolo[3,2-b]carbazole.
- Published
- 2013
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- View/download PDF
32. Supramolecular structure formation of Langmuir-Blodgett films of comblike precursor and polyimide
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V. V. Kudryavtsev, Iosif V. Gofman, Victor V. Luchinin, V. M. Pasyuta, V. P. Sklizkova, V. V. Rozanov, and S. I. Goloudina
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chemistry.chemical_classification ,Materials science ,Chemical structure ,Supramolecular chemistry ,General Chemistry ,Polymer ,Condensed Matter Physics ,Langmuir–Blodgett film ,chemistry ,Chemical engineering ,Monolayer ,Polymer chemistry ,Side chain ,Molecule ,General Materials Science ,Polyimide - Abstract
The surface structure of Langmuir-Blodgett films of a comblike polyimide precursor—a rigid-chain polyamic acid alkylamine salt bearing multichains of tertiary amine—and films of the corresponding polyimide were studied by atomic force microscopy (AFM). An analysis of the images of the surface of three-layer films revealed a domain structure. It was found that the Langmuir-Blodgett film formation of the precursor occurs as a result of the layer-by-layer deposition of two-dimensional domains (composed of polyamic acid salt molecules on the water surface) onto a substrate. The formation of domains in a monolayer is associated with the chemical structure of the precursor, to be more precise, with the rigidity of the main chain and the presence of closely spaced aliphatic side chains in the polymer chain, whose total cross-section area is close to the surface area of the projection onto the plane of the repeating unit of the main chain. Polyimide films inherit the domain structure of the precursor films; the inhomogeneity of the film thickness substantially decreases, whereas the domain size and character of their distribution in the film remain unchanged.
- Published
- 2013
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33. Heteroepitaxial growth of SiC films by carbonization of polyimide Langmuir-Blodgett films on Si
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Alexander N. Smirnov, V. V. Kudryavtsev, V.M. Svetlychnyi, S. I. Goloudina, Iosif V. Gofman, V. M. Pasyuta, Victor V. Luchinin, Demid A. Kirilenko, V. P. Sklizkova, M. F. Panov, and T. F. Semenova
- Subjects
Materials science ,Annealing (metallurgy) ,Scanning electron microscope ,Analytical chemistry ,Langmuir–Blodgett film ,Crystallography ,symbols.namesake ,Electron diffraction ,lcsh:TA1-2040 ,symbols ,High-resolution transmission electron microscopy ,Raman spectroscopy ,lcsh:Engineering (General). Civil engineering (General) ,Single crystal ,Polyimide - Abstract
High quality single crystal SiC films were prepared by carbonization of polyimide Langmuir-Blodgett films on Si substrate. The films formed after annealing of the polyimide films at 1000°C, 1100°C, 1200°C were studied by Fourier transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, transmission electon microscopy (TEM), transmission electron diffraction (TED), and scanning electron microscopy (SEM). XRD study and HRTEM cross-section revealed that the crystalline SiC film begins to grow on Si (111) substrate at 1000°C. According to the HRTEM cross-section image five planes in 3C-SiC (111) film are aligned with four Si(111) planes at the SiC/Si interface. It was shown the SiC films (35 nm) grown on Si(111) at 1200°C have mainly cubic 3C-SiC structure with a little presence of hexagonal polytypes. Only 3C-SiC films (30 nm) were formed on Si (100) substrate at the same temperature. It was shown the SiC films (30-35 nm) are able to cover the voids in Si substrate with size up to 10 μm.
- Published
- 2017
34. Photophysical and electrical properties of polyphenylquinolines containing carbazole or indolo[3,2-b]carbazole fragments as new optoelectronic materials
- Author
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R. Yu. Smyslov, Alexey R. Tameev, V. M. Svetlichnyi, V. V. Kudryavtsev, S. N. Stepanenko, T. N. Nekrasova, N. V. Matyushina, E. L. Aleksandrova, L. A. Myagkova, and Anatoly V. Vannikov
- Subjects
Materials science ,Carbazole ,Arylene ,Quinoline ,Quantum yield ,Alkylation ,Condensed Matter Physics ,Photochemistry ,Indolocarbazole ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Aniline ,chemistry ,Luminescence - Abstract
Photophysical and electrical properties of new synthesized 2,6-polyphenylquinolines (PPQs) containing an oxygen or phenylamine bridging group between quinoline cycles and, as an arylene radical, alkylated derivatives of carbazole or indolo[3,2-b]carbazole are studied. It is shown that the photosensitivity for new PPQs is 104–105 cm2/J and the photogeneration quantum yield of free carriers is as high as 0.15. Photophysical parameters increase with the phenylamine bridging group in place of the oxygen one and when using indolocarbazole instead of carbazole. It is found that a film of polyphenylquinoline containing an oxygen bridging group and an alkylcarbazole fragment in the polymer repeat unit exhibits “white” luminescence. Both electron and hole transport with a mobility of ∼10−6 cm2/(V s) are detected in films of all studied polymers. The conductivity value and type can be controlled by varying the chemical structure of the (oxygen or phenylamine) bridging group between PPQ cycles and by choosing carbazole or indolo[3,2-b]carbazole derivatives as an arylene radical.
- Published
- 2011
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35. Photophysical properties of indolo[3,2-b]carbazoles as a promising class of optoelectronic materials
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V. V. Kudryavtsev, T. N. Nekrasova, Valentin M. Svetlichnyi, N. V. Matushina, E. L. Alexandrova, S. N. Stepanenko, L. A. Miagkova, Alexey R. Tameev, and Anatoly V. Vannikov
- Subjects
Materials science ,Photoluminescence ,Carbazole ,Quantum yield ,Electroluminescence ,Condensed Matter Physics ,Photochemistry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Pentacene ,chemistry.chemical_compound ,chemistry ,Photosensitivity ,Optoelectronic materials ,Luminescence - Abstract
The photophysical properties of new synthesized indolocarbazoles, i.e., indolo[3,2-b]carbazole and its derivatives, have been comparatively analyzed. It is shown that their photosensitivity (total photosensitivity to (5–8) × 10−2 (lx s)−1, spectral photosensitivity ∼105 cm2 J−1, and free carrier photogeneration quantum yield of 0.1) and transport (effective mobility in 5,11-dioctyl indolo[3,2-b]carbazole is more than 10−5 cm2/(V s)) parameters significantly exceed those of pentacene, which, among molecular media (organic crystals), exhibits the highest carrier photogeneration quantum yields. The high photoluminescence intensity of synthesized indolo[3,2-b]carbazole derivatives shows promise for their applicability in electroluminescent devices.
- Published
- 2010
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36. Phase-inversion gradient-porous films on the basis of polyamidoimides derived from phthalimidobenzenedicarbonyl dichloride and various diamines
- Author
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E. V. Kruchinina, K. A. Romashkova, Andrey Shchukarev, V. V. Kudryavtsev, I. L. Potokin, and S. V. Kononova
- Subjects
chemistry.chemical_classification ,Condensation polymer ,X-ray photoelectron spectroscopy ,chemistry ,Chemical engineering ,Analytical chemistry ,General Chemistry ,Polymer ,Molding (process) ,Wetting ,Microporous material ,Porosity ,Phase inversion - Abstract
Morphology of microporous films prepared from aromatic polyamidoimides under different molding conditions was studied by scanning, transmission, and atomic force microscopy with the specific attention given to the nanosize skin layer. The films were manufactured by the phase inversion molding of aromatic polyamidoimides which were synthesized by low-temperature polycondensation of phthalimidobenzenedicarbonyl dichloride with various diamines. Comparison of the parameters of films, including their wettability and X-ray photoelectron spectroscopy data, gave additional information on factors affecting the mechanism of formation of microporous membranes in the system polymer (polyamidoimide)-solvent (N-methylpyrrolidin-2-one)-non-solvent (water).
- Published
- 2010
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37. Mechanical characteristics of films based on comb-shaped poly(amidoimides) with different contents of side chromophoric groups
- Author
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Iosif V. Gofman, M. Ya. Goikhman, V. V. Kudryavtsev, L. I. Subbotina, A. V. Yakimanskii, and I. V. Abalov
- Subjects
Structural organization ,Materials science ,Azo compound ,Polymers and Plastics ,Plasticizer ,Glycidyl ether ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Side chain ,Thermomechanical analysis ,Composite material ,Polarization (electrochemistry) ,Glass transition - Abstract
For films based on poly(amidoimide) with a comb-shaped structure and long side chains, the specific features of the mechanical and thermomechanical behavior and their dependence on the concentration of the above chains are studied. With variation of the composition of the material, changes in the mechanical characteristics show a nonmonotonic character. Comparison of the results of mechanical tests and densimetric measurements allows certain conclusions to be drawn about the character of variations in the structural organization of films with an increase in the concentration of side fragments in macrochains. The role of plasticization in the behavior of the above materials during heating is demonstrated. The advantages of the practical use of the above phenomena for the optimization of the regimes of thermally stimulated polarization of films are discussed.
- Published
- 2010
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- View/download PDF
38. Study of the supramolecular structure formation of comb-like polyimide precursor Langmuir-Blodgett films
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V. V. Kudryavtsev, S. I. Goloudina, Vera V. Klechkovskaya, Yu. G. Baklagina, V. M. Pasyuta, V. P. Sklizkova, Victor V. Luchinin, V. V. Rozanov, and M. F. Panov
- Subjects
chemistry.chemical_classification ,Langmuir ,Materials science ,Tertiary amine ,Supramolecular chemistry ,Salt (chemistry) ,General Chemistry ,Condensed Matter Physics ,Langmuir–Blodgett film ,chemistry ,Monolayer ,Polymer chemistry ,General Materials Science ,Prepolymer ,Polyimide - Abstract
The Langmuir monolayers and Langmuir-Blodgett films of a comb-like polyimide prepolymer (the rigid-chain polyamic acid alkylamine salt bearing multichains of tertiary amine) were studied. The supramolecular structures of the monolayers and Langmuir-Blodgett films of polyamic acid salts were characterized and a way for the surpamolecular structure to form was proposed based on an analysis of the surface pressure-area isotherms of monolayers on the water surface, investigations of the conditions of monolayer deposition onto solid substrates, and studies of the structures and surface morphology of Langmuir-Blodgett films.
- Published
- 2009
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39. Conducting film-forming composites based on polyaniline-polyimide blends
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G. K. Elyashevich, A. V. Yakimanskii, V. V. Kudryavtsev, I. G. Sushchenko, Tamara K. Meleshko, E. Yu. Rozova, V. M. Svetlichnyi, Iosif V. Gofman, and N. N. Bogorad
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Polyaniline nanofibers ,Polymer ,Conductivity ,Casting ,chemistry.chemical_compound ,chemistry ,Polyaniline ,Materials Chemistry ,Composite material ,Elongation ,Elastic modulus ,Polyimide - Abstract
A procedure is developed for preparing conducting films by their casting from polymer solutions containing polyaniline in the form of a protonated emeraldin base and polyimides in two cosolvents, N-methylpyrrolidone or m-cresol. Self-supporting films cast from composites based on polyimides and camphorsulfonic acid-protonated polyaniline combine a conductivity of 10−1−10−2S/cm with good mechanical properties: elastic modulus E = 2.0−2.4 GPa, breaking strength σb = 55−60 MPa, and elongation at break ɛb = 8−10%. It has been shown that, when m-cresol and N-methylpyrrolidone are used as cosolvents, the maximum film conductivity is achieved at polyaniline amounts in the composites of 20 and 3%, respectively. In the latter case, films with good strength parameters are formed.
- Published
- 2009
- Full Text
- View/download PDF
40. Photoelectric and electrical properties of soluble polyphenylquinolines containing an oxygen or phenylamine bridge group between quinoline moieties
- Author
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E. L. Aleksandrova, V. M. Svetlychnyi, V. V. Kudryavtsev, Alexey R. Tameev, Anatoly V. Vannikov, T. N. Nekrasova, and L. A. Miagkova
- Subjects
chemistry.chemical_classification ,Materials science ,Quinoline ,Quantum yield ,Polymer ,Conductivity ,Photoelectric effect ,Condensed Matter Physics ,Photochemistry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Aniline ,chemistry ,Photosensitivity ,Charge carrier - Abstract
Photoelectric and electrical properties of polyphenylquinolines differing in the structure of donor bridge groups between quinoline moieties have been studied. It is demonstrated that films of the polymers synthesized exhibit a photosensitivity at the level of 105 cm2 J−1 (integrated sensitivity 5 × 10−4 lx−1 · s−1), with a quantum yield of carrier photogeneration of 0.07 and a carrier drift mobility on the order of 10−6 cm2 V−1 s−1. The fact that the electron and hole drift mobilities in polyphenylquinoline with a phenylamine bridge group are balanced makes the polymer promising for development of film-type devices based on the bipolar conductivity of a material (e.g., single-layer light-emitting diode).
- Published
- 2009
- Full Text
- View/download PDF
41. Photosensitivity of polyimides and polyquinazolones based on aromatic and heteroaromatic diamines
- Author
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K. A. Romashkova, N. A. Solovskaya, V. V. Kudryavtsev, G. I. Nosova, E. A. Aleksandrova, and A. V. Yakimanskii
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Oxadiazole ,Polymer ,Benzoxazole ,Triphenylamine ,Photochemistry ,chemistry.chemical_compound ,chemistry ,Benzothiazole ,Diamine ,Polymer chemistry ,Materials Chemistry ,Imide ,Polyimide - Abstract
Soluble polyimides containing triphenylamine residues as substituents at the imide nitrogen atom and polyquinazolones with diphenyl oxide, diphenylpropane, benzimidazole, benzoxazole, benzothiazole, oxadiazole, and triphenylamine moieties in the diamine component of the repeating unit have been synthesized. The spectroscopic study of polyquinazolones indicates their capability for donor-acceptor interactions. Emission bands of the polymers are of the exciplex nature. The photogeneration of current carriers in the polymers under study has been examined by the method of surface potential photoinduced decay. It has been shown that the intrinsic photosenitivity of polyquinazolones is nearly the same as (or somewhat higher than) that of the corresponding polyimides, but the former polymers are characterized by a less efficient spectral sensitization by dyes and donor-acceptor additives.
- Published
- 2008
- Full Text
- View/download PDF
42. Local forms of molecular mobility in comb-shaped chromophore-containing copoly(methacrylates)
- Author
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A. V. Yakimanskii, Nikolai N. Smirnov, N. A. Nikonorova, and V. V. Kudryavtsev
- Subjects
Azo compound ,Materials science ,Polymers and Plastics ,Relaxation (NMR) ,Activation energy ,Chromophore ,Dielectric spectroscopy ,chemistry.chemical_compound ,Dipole ,Crystallography ,chemistry ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Side chain - Abstract
The local forms of molecular mobility of comb-shaped random copoly(methacrylates) have been studied by the method of dielectric spectroscopy. Side branches of these copolymers are composed of alternating chromophore-containing chains and flexible fluoromethylene sequences. Two regions of relaxation of dipole polarization, γ2 and β processes, related to the mobility of end polar groups and the reorientation of chromophore groups relative to their long axes, respectively, have been discovered in the glassy state. The times of relaxation of the γ2 process depend on the ratio between the flexible and rigid parts of the copolymer. In the region of the β process, the molecular mobility appears to be slightly dependent on the chromophore structure and its intensity is determined by the degree of substitution of chromophore groups.
- Published
- 2008
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43. New Cu(I) complexes with biquinolyl-containing polymer ligands as electrocatalysts for O2 activation in the oxidation of alcohols
- Author
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V. V. Kudryavtsev, Alexander V. Dolganov, Irina V. Podeshvo, Mikhail Ya. Goikhman, Alexander V. Yakimansky, and Tatiana V. Magdesieva
- Subjects
chemistry.chemical_compound ,chemistry ,Ligand ,General Chemical Engineering ,Alcohol oxidation ,Inorganic chemistry ,Electrochemistry ,Acetonitrile ,Electrocatalyst ,Redox ,Macromolecule ,Catalysis - Abstract
Electrochemical approach to a new electroactive catalytic system based on polyamic acids with biquinolyl (biQ) fragments in the polymer backbone capable of coordination to Cu(I)-ions was elaborated using sacrificial Cu anode. The redox properties of the resultant Cu(I) polymer complex were characterized by voltammetric methods. Polynuclear Cu(I) complex with only one biQ ligand per Cu(I) center showed high oxidase activity in air oxidation of aliphatic and aromatic alcohols to corresponding carbonyl derivatives with concomitant reduction of molecular oxygen to water. The reactions proceed in acetonitrile or N -methylpyrrolidone at a potential of Cu II /Cu I electroreduction (−0.55 V versus Ag/AgCl/KCl) with the high preparative yield and current efficiency. The electrocatalytic efficiency is enhanced when the Cu-containing polymer is immobilized on the graphite surface. The stoichiometric composition of the adsorbed polymer complex was determined by means of coulometric assays of the quantities of electroactive biQ fragments and Cu(I) present on the surface. The possibility of the obtained redox-active macromolecules to mimic the active site of certain copper-containing enzymes capable of reversible binding and activation of dioxygen is discussed, providing some insight into the mechanism of the catalytic process.
- Published
- 2008
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44. Light sensitivity of photoconducting polymer systems with polymethine dyes based on derivatives of 2(4)-methylquinoline and indole
- Author
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E. L. Aleksandrova, V. V. Kudryavtsev, Inna M. Sokolova, V. N. Ivanova, V. I. Frolov, O. A. Nagibina, and G. K. Lebedeva
- Subjects
Indole test ,chemistry.chemical_classification ,Conductive polymer ,Materials science ,business.industry ,Photoconductivity ,Relaxation (NMR) ,Quantum yield ,Polymer ,Electronic structure ,Condensed Matter Physics ,Photochemistry ,Electronic, Optical and Magnetic Materials ,chemistry ,Photosensitivity ,Optoelectronics ,business - Abstract
The photosensitivity of conducting polymer films with newly synthesized polymethine dyes is investigated. It is demonstrated that the photosensitivity of polymer films based on poly(o-hydroxyamide) with transport indole molecules forming intermolecular complexes with dyes is two or three times higher than the photosensitivity of the polymer films containing indole as a structural component of the dye. The introduction of the indole-containing dye into the photoconducting poly(vinylcarbazole) leads to an increase in the photo-conductivity by one and a half orders of magnitude. In this case, the quantum yield increases to η = 0.085. A correlation is revealed between the electronic structure of the dyes, the characteristics of the photoconduction in the materials under investigation, and the mechanisms of charge relaxation in the samples. An increase in the photoconductivity of the films results in the crossover from the drift mechanism of charge relaxation to the relaxation mechanism associated with intrinsic electrical conduction.
- Published
- 2007
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45. Electrochemical synthesis of Cu-containing polyheteroarylenes and study of their catalytic properties
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M. Ya. Goikhman, Irina V. Podeshvo, Alexander V. Dolganov, V. V. Kudryavtsev, A. V. Yakimanskii, and Tatiana V. Magdesieva
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chemistry.chemical_compound ,Monomer ,chemistry ,Hydroquinone ,Ligand ,Inorganic chemistry ,Electrochemistry ,chemistry.chemical_element ,Electrocatalyst ,Copper ,Quinone ,Catalysis - Abstract
Method of electrochemical synthesis of new Cu-containing polyheteroarylenes that have biquinolyl units in their main chain is developed on the base of the soluble anode technique. The study of electrochemical properties of thus obtained Cu-containing polymer and the corresponding monomer complex revealed existence of two types of coordination environment: (1) copper Cu(I) in the tetrahedral surrounding of two biquinolyl ligands and (2) copper Cu(I) bound with only one biquinolyl fragment. The complexes with one biquinolyl polymer ligand showed high activity as catalysts for O2 reduction in the presence of hydroquinone that is converted to quinone in the course of the reaction.
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- 2007
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46. Synthesis and properties of glycidyl methacrylate copolymers with side chromophore groups
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N. N. Smirnov, K. A. Romashkova, V. A. Lukoshkin, L. I. Subbotina, A. V. Yakimanskii, A. Yu. Ershov, V. V. Kudryavtsev, Iosif V. Gofman, and M. Ya. Goikhman
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chemistry.chemical_classification ,Glycidyl methacrylate ,Polymers and Plastics ,Carboxylic acid ,Chemical modification ,Epoxide ,Polymer ,Chromophore ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Materials Chemistry ,Copolymer ,Methyl methacrylate - Abstract
A number of styrylquinoline chromophores with carboxyl groups have been prepared through the interaction of 2-methylcinchonic acid with aromatic aldehydes of various chemical structures. The copolymer of glycidyl methacrylate and methyl methacrylate carrying side epoxide groups has been synthesized, and the chemical modification of the copolymer with the above chromophores has been performed. The thermal, spectral, and nonlinear optical properties of the chromophores and modified polymers have been studied.
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- 2007
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47. Electrochemical and quantum chemical investigation of the CuI and CuII complexes with biquinolyl monomer and polymer ligands
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T. V. Magdesieva, V. V. Kudryavtsev, Alexander V. Dolganov, A. V. Yakimanskii, Irina V. Podeshvo, P. M. Polestchuk, and M. Ya. Goikhman
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chemistry.chemical_classification ,Electrolysis ,General Chemistry ,Polymer ,Electrochemistry ,Photochemistry ,Redox ,law.invention ,Crystallography ,chemistry.chemical_compound ,Monomer ,chemistry ,law ,Polyamide ,Ionization energy ,Cyclic voltammetry - Abstract
Structural reorganization of polyamide (PA) and low-molecular-weight CuI and CuII complexes with biquinolyl (biQ) ligands during their mutual redox transformations in solution was studied using the electrochemical methods (cyclic voltammetry and preparative electrolysis) and quantum chemical DFT calculations. The influence of electronic factors and geometry distortions in the complexes on the ionization energy on going from CuI to CuII was evaluated in comparison. The catalytically active form of the [CuI(PA)L2]BF4 complex can be synthesized in situ from the stable tetrahedral complex [CuI(PA)2]BF4 by the series of successive redox transitions CuI → CuII → CuI accompanied by the loss of one biQ-containing macroligand.
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- 2007
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48. Molecular mobility in comb-shaped copoly(methacrylates) with fluoromethylene and chromophore-containing side chains
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V. V. Kudryavtsev, N. V. Afanas’eva, A. V. Yakimanskii, N. A. Nikonorova, N. A. Solovskaya, Nikolai N. Smirnov, G. I. Nosova, and K. A. Romashkova
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chemistry.chemical_classification ,Materials science ,Azo compound ,Polymers and Plastics ,Relaxation (NMR) ,Polymer ,Dielectric ,Chromophore ,chemistry.chemical_compound ,Crystallography ,Dipole ,chemistry ,Polymer chemistry ,Materials Chemistry ,Side chain ,Polarization (electrochemistry) - Abstract
The molecular mobility of copoly(methacrylates) with chromophore-containing side groups of various structures has been studied by the dielectric method. The region of relaxation of dipole polarization related to the segmental mobility (α process) has been discovered. At temperatures that are ∼30°C higher than those corresponding to the α process, the relaxation transition reflecting the reorientation of chromophore-containing side groups (δ process) takes place. It is suggested that the occurrence of the δ process is a general phenomenon for such systems. This effect allows one to determine the temperature at which the polarization of polymer films under application of corona discharge should be carried out so that a high level of nonlinear optical properties associated with the macroscopic noncentrosymmetrical orientation of chromophores may be achieved.
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- 2007
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49. Deactivation pathways of the electronic excitation of ions of lanthanide complexes in polymers with functional groups
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A. V. Shablya, Valerii L Ermolaev, V. V. Kudryavtsev, M. Ya. Goĭkhman, E. B. Sveshnikova, A. V. Yakimanskiĭ, and Irina V. Podeshvo
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chemistry.chemical_classification ,Diketone ,Lanthanide ,Coordination sphere ,Polymer ,Photochemistry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Ion ,chemistry.chemical_compound ,chemistry ,Absorption band ,Luminescence ,Thenoyltrifluoroacetone - Abstract
Complexes Eu(TTA)3phen and Eu(MBTA)3phen, as well as complexes Tb(MBTA)3phen and Tb(TTA)3phen, which do not luminesce in solutions, are shown to luminesce in polymer films (TTA is thenoyltrifluoroacetone, MBTA is n-methoxybenzoyltrifluoroacetone, and phen is o-phenanthroline). Luminescence of complexes of Eu and Tb in films of a polymer, poly(methylene-bis-anthranilamide) 1,6-hexamethylenedicarboxylic acid (PAA-5), having a high concentration of functional anthranilate groups, is studied. From the behavior of the luminescence intensity (I lum), the luminescence decay time, and the luminescence spectra of complexes of these lanthanides in polymer films, the following regular features were revealed. (i) During the film preparation at 90°C, Ln complexes are attached to PAA-5 via anthranilate groups. (ii) Irradiation of these films in the range of the absorption band of ligands (TTA or MBTA) leads to deactivation of the electronic excitation of ions according to the diketone detachment mechanism and to further binding of complexes to polymers. In this case, I lum(Eu(III)) decreases because the introduction of anthranilate groups of the polymer into the first coordination sphere of Eu(III) complexes enhances the nonradiative deactivation of these ions, whereas I lum(Tb(III)) increases since the introduction of these groups suppresses the nonradiative deactivation of Tb complexes through triplet states of ligands (TTA and MBTA). (iii) Upon storage of films in the dark (20°C), complexes detach themselves from the polymer and return to their initial structure. In PAA-5 films into which Eu and Tb complexes were simultaneously introduced, the color of the emission from the irradiation spot changes from red to green.
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- 2007
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50. Structuring in mixed solvents: Study by polarized light scattering
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V. V. Kudryavtsev, Elena N. Vlasova, N. A. Kalinina, Alexander P. Filippov, V. P. Sklizkova, I. G. Silinskaya, and A. M. Bochek
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chemistry.chemical_compound ,Wavelength ,Structural organization ,Polymers and Plastics ,Distilled water ,chemistry ,Chemical engineering ,Scattering ,Amide ,Materials Chemistry ,Supramolecular chemistry ,Organic chemistry ,Polyimide - Abstract
The structure of mixed amide solvents used for the preparation of polyimide Langmuir-Blodgett films and the structural organization of water, on which nanofilms are formed, have been studied by polarized light scattering. Fluctuation supramolecular structures are found to exist in water and in its mixtures with amide solvents, and the dimensions of the structures are comparable with the light wavelength. When a mixture contains more than 20 vol % water, associates show microanisotropic properties. In snowmelt water, the dimensions of associates are larger than those in distilled water. In the DMAA-water mixture, the dimensions of supramolecular structures are virtually independent of composition.
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- 2007
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Catalog
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