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1.
E. A. Sanginov A. N. Panin S. L. Saratovskikh N. M. Bravaya 《Polymer Science Series A》2006,48(2):99-106
For two stereospecific metallocene catalysts, namely, syndiospecific Ph2CCpFluHfMe2 and isospecific rac-Me2SiInd2ZrMe2, the introduction of Lewis bases into a reaction medium was shown to promote a marked rise in the efficiency of catalytic systems. In the case of the syndiospecific metallocene, the maximum effect of the base (a 10-fold increase in activity) was achieved using the (Ph2CCpFluHfMe2 + Ph3N)/CPh3B(C6F5)4 catalytic system in the presence of Al-i-Bu3 at a molar ratio of Al: Hf: B: N = 15: 1: 1: 1. When the polymerization of propylene was carried out in the presence of Al-i-Bu3 and Ph3N, an elastomeric stereoblock syndio/atactic polypropylene was produced. For the (rac-Me2SiInd2ZrMe2 + amine)/CPh3B(C6F5)4 catalytic system, a 15-to 30-fold increase in activity was observed upon introduction of amines of the aniline type: Me2NPh, Me-n-BuNPh, and NPh3. 相似文献
2.
Ponomarev A. N. Kritskaya D. A. Abdrashitov E. F. Bokun V. Ch. Sanginov E. A. Novikova K. S. Dobrovol’skii Yu. A. 《Russian Journal of Electrochemistry》2019,55(8):738-744
Russian Journal of Electrochemistry - Abstract—The thermal polymerization of styrene sorbed from the gas-phase into polymer films of polyvinylidene fluoride (PVDF) is carried out at... 相似文献
3.
A. N. Ponomarev E. F. Abdrashitov D. A. Kritskaya V. Ch. Bokun E. A. Sanginov Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2017,53(6):589-607
Methods for the preparation of composite ion-exchange membranes from polymer (polyvinylidene fluoride (PVDF), ultrahigh molecular weight polyethylene (UHMWPE), and polypropylene (PP)) matrices were considered. Polystyrene (PS) was introduced in the matrices by thermal polymerization of the monomer followed by sulfonation of the implant. The fundamentals of membrane synthesis from industrial polytetrafluoroethylene (PTFE, Teflon F-4) films by thermal polymerization of styrene in a film stretched in a monomer solution followed by sulfonation of incorporated PS were described. The literature on radiation- chemical synthesis of composite ion-exchange membranes based on polymer matrices with embedded polystyrene and its subsequent sulfonation was analyzed. Some problems of the kinetics and mechanism of thermal implantation of PS into various polymer matrices under different conditions were discussed. The physicochemical characteristics, structure, and transport properties of the membranes synthesized by thermal implantation of PS were reported. The obtained membranes were tested in low-temperature fuel cells. 相似文献
4.
E. F. Abdrashitov V. Ch. Bokun D. A. Kritskaya E. A. Sanginov A. N. Ponomarev Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2011,47(4):387-394
Thermal polymerization of styrene sorbed into a polyvinylidene fluoride (PVdF) film from a toluene solution followed by sulfonation
of the resulting material was performed. The kinetics of polystyrene (PS) accumulation in the PVdF film during thermal polymerization
was studied. Samples with 6–30 wt % PS and ∼100% PS sulfonation were obtained. Proton-exchange membranes wsith an ion-exchange
capacity of up to 2 mg-eq/g and proton conductivity of up to 0.008 S/cm at 75% relative humidity were prepared. The permeability
coefficients of water, methanol, and hydrogen and their dependences on the amount of introduced PS, ion-exchange capacity,
and water uptake of membranes were measured. The synthesized materials proved similar to MF-4SK membranes in their basic transport
characteristics and can be used as proton-exchange membranes in hydrogen-air and alcohol fuel cells. 相似文献
5.
Zyubin A. S. Zyubina T. S. Sanginov E. A. Kayumov R. R. Shmygleva L. V. Dobrovol’skii Yu. A. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(5):901-907
Russian Journal of Physical Chemistry A - Quantum chemical modeling is performed for the distancing of lithium and ammonium cations from the –O–CF2–CF2–SO$$_{3}^{ - }$$... 相似文献
6.
E. Yu. Voropaeva E. A. Sanginov V. I. Volkov A. A. Pavlov A. S. Shalimov I. A. Stenina A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2008,53(10):1536-1541
Proton transport in MF-4SK perfluorinated sulfo cationic membranes modified by silica and zirconium hydrogen phosphate were studied using pulsed-field gradient NMR and impedance spectroscopy. At high water contents, water molecules are involved in proton transfer. At low water contents, the proton conductivity of modified membranes considerably exceeds the conductivity of an unmodified membrane. The most likely reason for this effect is the generation of an extra H-bond network involving the dopant and sulfo groups of the membrane. 相似文献
7.
V. I. Volkov E. V. Volkov S. V. Timofeev E. A. Sanginov A. A. Pavlov E. Yu. Safronova I. A. Stenina A. B. Yaroslavtsev 《Russian Journal of Inorganic Chemistry》2010,55(3):318-324
Water self-diffusion and ion mobilities in various ionic forms (H+, Li+, Na+, Rb+, Cs+, and Ba2+) of perfluorinated sulfocationic membranes MF-4SK were studied by NMR and impedance spectroscopy. When degrees of hydration
are low, the self-diffusion coefficients of water and ionic conductivities are considerably affected by the water content
of the membrane. The self-diffusion coefficients decrease in the order H+ > Ba2+ > Cs+ > Rb+ > Na+ > Li+, whereas the ion mobility decreases in the order H+ > Li+ > Na+ > Cs+ > Ba2+. 相似文献
8.
S. L. Shestakov E. V. Korostylev S. V. Timofeev A. V. Maksimychev S. G. Vasil’ev E. A. Sanginov Yu. A. Dobrovol’skii V. I. Volkov 《Russian Journal of Electrochemistry》2011,47(4):395-403
Based on perfluorinated polymers MF-4SK and F-4KF bilayer composite ion-exchange membranes are studied by using the magic-angle-rotation
NMR, electrochemical impedance spectroscopy, scanning electron microscopy, and electron-probe microanalysis. It is shown that
the contact of the polymers includes an interlayer, approximately 5 μm thick. The NMR data point to slow water-molecules-exchange
between hydrate-complexes of sulfo- and carboxyl-groups. 相似文献
9.
Lyubov Shmygleva Evgeny Sanginov Nikita Slesarenko Aleksander Chernyak Aleksander Karelin Yury Dobrovolsky 《Ionics》2017,23(7):1793-1800
The features of proton transport and proton hydration shell structure of calix[6]arene sulfonic acid were studied. XRD and NMR data indicate the existence of crystalline and amorphous phases and various conformations in the acid structure. The hydration process occurs in three stages by thermal analysis and IR spectroscopy. The change in the composition of the hydrate affected the conductivity only at low humidity; an inverse relationship between the water uptake and the activation energy of conductivity is observed in the entire investigated range of humidity. 相似文献
10.
A. A. Arslanova E. A. Sanginov Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2018,54(3):318-323
New composite membranes based on commercial perfluorinated Nafion-115 membrane and cross-linked sulfonated polystyrene were synthesized and investigated. The membranes were prepared by radical polymerization of styrene in the presence of a cross-linking agent divinylbenzene in Nafion polymer matrix and subsequent sulfonation of formed polystyrene. The membranes containing approximately 5 and 10 wt % of cross-linked polystyrene with ion-exchange capacity of 1.1 to 1.3 mg-eq/g were obtained. Modification with sulfonated polystyrene leads to an increase in the moisture content and proton conductivity of membranes in the humidity range of 15 to 100 RH. 相似文献