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  • Synthesis of Pentablock Copolymers of the Mixed Linear-Brush Topology by Controlled Radical Polymerization and Ring-Opening Polymerization Reactions
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    A. V. Kashina, T. K. Meleshko, N. N. Bogorad, M. A. Bezrukova, A. V. Yakimanskii

    Controlled atom-transfer radical polymerization and ring-opening polymerization methods are used for the first time to synthesize symmetric pentablock copolymers with a central block, which is a polymer brush with the polyimide backbone and poly(methyl methacrylate) side chains, and outer linear block copolymers of poly(ε-caprolactone) with poly(methyl methacrylate). The chemical structure of the polymers is studied by 1H NMR spectroscopy. The molecular weight characteristics of the synthesized pentablock copolymers are determined by multidetector size exclusion liquid chromatography. It is shown that these characteristics are in good agreement with the absolute molecular weights obtained by sedimentation-diffusion analysis.

    更新日期:2019-12-11
  • Cyclododecene in Olefin Metathesis: Polymerization and Macromolecular Cross-Metathesis with Polynorbornene
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    Yu. I. Denisova, V. A. Zhigarev, M. L. Gringolts, G. A. Shandryuk, A. S. Peregudov, E. Sh. Finkelshtein, Y. V. Kudryavtsev

    The reaction of macromolecular cross-metathesis of polynorbornene and polydodecenamer catalyzed by the first-generation Grubbs Ru-carbene complex is studied for the first time. Polydodecenamer with high-molecular-weight characteristics (Mw = 406 × 103, Ð = 2.5) and a yield of 96% is synthesized by the ring-opening metathesis polymerization of cyclododecene mediated by the second-generation Grubbs catalyst. The polymer has a melting temperature of 62–83°C, depending on the content of trans double bonds, and shows poor solubility in organic solvents at room temperature. Its cross-metathesis with polynorbornene at 40°С gives rise to new statistical multiblock copolymers of norbornene and cyclododecene with different degree of blockiness. NMR, GPC, and DSC were used to investigate the effect of reaction conditions on the structure and thermal properties of the copolymers. At the initial step of the reaction, along with a high-molecular-weight peak, the GPC chromatograms exhibit a peak due to the low-molecular-weight fraction (M = (1–2) × 103), suggesting the formation of cyclooligomers. With increasing degree of interchain exchange, the proportion of the oligomeric fraction decreases appreciably. The kinetics of the cross-metathesis of polynorbornene with polydodecenamer and polyoctenamer at 40°С is studied by in situ 1Н NMR spectroscopy and ex situ 13С NMR spectroscopy. The rates of elementary reactions in these blends differ insignificantly, except for the conversion stage of the initial carbenes into polymer ones. The formation rate for carbene [Ru]=polyoctenamer is three times higher than the formation rate for the [Ru]=polydodecenamer carbene. In both cases, the fraction of Ru carbenes attached to norbornene units is extremely small throughout the process.

    更新日期:2019-12-11
  • Promising Catalytic Processes of Dicyclopentadiene Metathesis Polymerization to Obtain a New Class of Polymeric and Polymer–Composite Materials
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    V. V. Afanas’ev, T. M. Yumasheva, N. B. Bespalova

    A lineup of highly efficient ruthenium catalysts with N-containing substituents in the benzylidene ligand is developed that differ in the rate of initiation of dicyclopentadiene metathesis polymerization. The choice of the optimal catalyst makes it possible to control the lifetime of the monomer–catalyst reaction mixture in a wide range, which makes the use of various technologies effective for the production of polymer and composite materials. The new catalysts have been used to design a series of innovative polymer and polymer-composite materials with a polymer matrix based on a finished monomer, dicyclopentadiene, which is a raw material of the petrochemical industry. The polymeric materials are distinguished by a unique combination of high mechanical properties and good thermal stability in a wide temperature range (from –60 to +320°C), which allows their use in various climatic zones. Composites with a matrix based on polydicyclopentadiene are not inferior to commercially available counterparts based on epoxy and polyester resins and even surpass them in a number of parameters.

    更新日期:2019-12-11
  • Synthesis, Molecular, and Gas-Transport Properties of Homopolymers Based on 5-Ethylidene-2-norbornene and 5-Vinyl-2-norbornene
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    E. V. Bermesheva, A. I. Wozniak, I. L. Borisov, N. P. Yevlampieva, O. S. Vezo, G. O. Karpov, M. V. Bermeshev, A. F. Asachenko, M. A. Topchiy, P. S. Gribanov, M. S. Nechaev, V. V. Volkov, E. Sh. Finkelshtein

    Using the commercial derivative of norbornene—5-ethylidene-2-norbornene—a series of three isomeric homopolymers with different structure of the backbone is synthesized, and the effect of the chain structure on the gas-transport behavior of polynorbornenes is studied. The gas-transport characteristics of the polymers are presented together with data on the conformation properties of molecules of addition and metathesis polynorbornenes. The effect of the structure of side substituents on the equilibrium rigidity of addition polynorbornenes is confirmed by the example of poly(5-ethylidene-2-norbornene) and poly(5-vinyl-2-norbornene).

    更新日期:2019-12-11
  • Ruthenium–Carbene Complexes in the Synthesis of Polybutadiene and Its Cross-Metathesis with Polynorbornene
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    A. A. Morontsev, M. L. Gringolts, M. P. Filatova, A. S. Peregudov, T. R. Akmalov, S. M. Masoud, S. N. Osipov, Yu. I. Denisova, Y. V. Kudryavtsev

    The activity of known and newly synthesized Ru-carbene catalysts in the metathesis polymerization of 1,5-cyclooctadiene and interchain cross-metathesis of synthesized polybutadiene with polynorbornenes is studied. First- and second-generation Grubbs Ru-complexes, second-generation Hoveyda–Grubbs complexes, and their modified analogs with asymmetric fluoro-containing ligands and unsaturated imidazolyl moieties are used as catalysts. It is shown that in the presence of the second-generation modified and nonmodified catalysts a partially crystalline polybutadiene is formed, in which blocks with trans-С=С bonds are about four times longer than blocks containing cis-С=С bonds. In the case of catalysts with bulkier ligands, the length of trans blocks is smaller and the melting temperature of the polymer is lower. The activities of the catalysts are compared by in situ 1Н NMR monitoring. New norbornene-butadiene multiblock copolymers are prepared for the first time by cross-metathesis between polybutadiene and polynorbornene. The highest degree of blockiness of the copolymers is attained when using second-generation Grubbs and Hoveyda–Grubbs catalysts. The activity sequences for the studied catalysts are constructed. It is shown that macromolecular cross-metathesis occurs more intensively in the presence of the catalysts with less bulky ligands.

    更新日期:2019-12-11
  • Radical Substitution of the Dithiocarbonyl Group of Poly(methyl methacrylate) Obtained by Reversible Addition–Fragmentation Chain Transfer Polymerization
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    M. Z. Bekanova, N. K. Neumolotov, A. D. Jablanovic, A. V. Plutalova, E. V. Chernikova

    The authors perform a systematic study of the reaction of radical replacement of the dithiocarbonyl group of poly(methyl methacrylate) (PMMA) obtained by reversible addition–fragmentation chain transfer polymerization upon interaction with a radical azo initiator in an inert solvent at 80°C. It is shown that, for a polymer with a dithiobenzoate group, an increase in the molar ratio of the concentrations of the initiator and macromolecules with a terminal dithiobenzoate group to 100 equivalents promotes fast and quantitative replacement of the dithiobenzoate group by the initiator fragment and suppression of side chain termination reactions with the participation of radical intermediates. To replace the trithiocarbonate group, milder conditions are required, namely, a 20-fold molar excess of the initiator and a short reaction time of 2–5 h. The stability of the radical intermediates plays the decisive role in choosing the replacement reaction conditions. The reversible chain transfer agent formed during the replacement reactions, a low-molecular-weight compound containing a dithiocarbonyl fragment, can be repeatedly used for PMMA synthesis.

    更新日期:2019-12-11
  • Synthesis and Gas-Separation Properties of New Silacyclopentane-Containing Polynorbornenes
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    V. A. Zhigarev, A. A. Morontsev, R. Yu. Nikiforov, M. L. Gringolts, N. A. Belov, N. G. Komalenkova, V. G. Lakhtin, E. Sh. Finkelshtein

    Previously, it was shown that the presence of bulky silicon-containing substituents in the monomer unit of metathesis polynorbornenes hinders the postmodification and, in particular, exhaustive gem-difluorocyclopropanation of main-chain double bonds. In order to reduce the double bonds shielding by substituents, a new polynorbornene with a dimethylsilacyclopentane fragment in the monomer unit, poly(4,4-dimethyltricyclo[5.2.1.02,6]-4-siladec-8-ene) (PNBCP), is synthesized, in which the silylmethyl group is moved further from the double bonds. In order to achieve this, the monomer 4,4-dimethyltricyclo[5.2.1.02,6]-4-siladec-8-ene (NBCP) is first obtained via the diene condensation of 1,3-cyclopentadiene and 1,1-dichlorosilacyclopent-3-ene with following methylation of Si-Cl bonds. NBCP is polymerized by the ring-opening metathesis scheme in the presence of the first-generation Grubbs catalyst, Cl2(PCy3)2Ru=CHPh. The new polymer PNBCP is obtained in a yield of 99–100% and characterized. The gem-difluorocyclopropanation of PNBCP with difluorocarbene, generated during the thermolysis of sodium chlorofluoroacetate, is studied; the conditions for exhaustive replacement of double bonds by gem-difluorocyclopropane are found. It is shown that PNBCP is more active in postmodification compared to poly(5-trimethylsilyl)norbornene but is less active than unsubstituted polynorbornene. It is demonstrated that the introduction of the silacyclopentane fragment into the monomer unit of the metathesis polynorbornene and its subsequent difluorocyclopropanation lead to increase in gas permeability and diffusion and cause a slight decrease in ideal separation selectivities. It is found that gem-difluorocyclopropanation increases the glass transition temperature of PNBCP by 60°C and makes its films stable when stored in air.

    更新日期:2019-12-11
  • Metathesis Polymerization in Ionic Media
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    D. O. Ponkratov, A. S. Shaplov, Ya. S. Vygodskii

    The article summarizes the literature data on polymer synthesis by olefin and acetylene metathesis in ionic liquid media—salts in the liquid state—at room temperature or close to it. The features and methods of optimization of polymerization process in ionic media, including those using ionic catalysts are discussed. The possibility of multiple use of ionic solvents and catalysts dissolved in them is demonstrated. Data on the polymerization of ionic monomers and the prospects for using ionic polymers obtained by metathesis polymerization are presented.

    更新日期:2019-12-11
  • Kinetics of Dicyclopentadiene Polymerization in the Presence of the Second Generation Hoveyda-Grubbs Catalyst with N -Chelating Ligand
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    A. A. Lyapkov, L. S. Soroka, R. V. Ashirov, D. I. Zemlyakov, D. A. Rusakov, F. Verpoort

    This article considers the thermodynamic aspects, thermo- and rheokinetics of endo-dicyclopentadiene polymerization in the presence of the original metathesis second Hoveyda-Grubbs catalyst with an N-chelating ligand. The activation energy of endo-dicyclopentadiene polymerization was determined as 88.9–89.2 kJ/mol. The thermal effect of the ring-opening metathesis endo-dicyclopentadiene polymerization reaction reaches 52.7 kJ/mol. This is lower than the values for molybdenum- and tungsten-containing catalysts reported in the literature, which can be explained by a different microstructure of the polymer produced in the presence of ruthenium-based metathesis catalysts.

    更新日期:2019-12-11
  • Polymerization of Tricyclononenes
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    E. Sh. Finkelshtein, P. P. Chapala, M. L. Gringolts, Yu. V. Rogan

    The expansion of the range of available and reactive monomers allowing preparation of novel polymeric materials, is an actual task of polymer chemistry. This mini-review is devoted to the polymerization of tricyclo [4.2.1.02,5]non-7-enes (tricyclononenes) and tricyclo[4.2.1.02,5]nona-3,7-dienes (tricyclonona-dienes)–norbornene type monomers containing norbornene and cyclobutane or cyclobutene fragments in the molecules. Their synthesis is carried out using available cyclopentadiene or quadricyclane, which is a product of norbornadiene photo-isomerization. The features of ring-opening metathesis and addition polymerization of tricyclononenes with participation of double bond in the norbornene fragment are highlighted. Examples of the polymerization of a wide range of tricyclononenes with F-, Si-, O-, and N-containing substituents have demonstrated that they are noticeably more active monomers than norbornenes with the same substituents. The main successes have been achieved in the synthesis of F- and Si-substituted polytricyclononenes, which are promising materials for lithography and membrane gas separation.

    更新日期:2019-12-11
  • Cross-Metathesis between Polynorbornene and Poly(5,6-epoxy-1-octenamer)
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    A. V. Roenko, Yu. I. Denisova, M. L. Gringolts, A. S. Peregudov, G. A. Shandryuk, E. Sh. Finkelshtein, Y. V. Kudryavtsev

    The macromolecular reaction of interchain cross-metathesis between polynorbornene and poly(5,6-epoxy-1-octenamer) in the presence of the first-generation Grubbs catalyst is studied. Chemically stable poly(5,6-epoxy-1-octenamer) is obtained through metathesis polymerization of 5,6-epoxycyclooct-1-ene with the second-generation Grubbs ruthenium catalyst. New random multiblock copolymers of norbornene and 5,6-epoxycyclooct-1-ene with different average block lengths determined by the reaction time, solvent type, and concentrations of the catalyst and initial homopolymers are synthesized and characterized by NMR, GPC, and DSC. Despite a distance between the epoxy substituent and the reaction center (double bond), poly(5,6-epoxy-1-octenamer) shows a lower activity in the cross-metathesis reaction with polynorbornene compared to unsubstituted polyoctenamer. The influence of epoxy groups present in the backbones of homopolymer and norbornene–cyclooctene multiblock copolymers on their thermal characteristics is studied. It is shown that the glass transition and melting temperatures increase with the concentration of epoxy groups upon the incorporation of an oxirane fragment into both homopolymers and copolymers. The crystallinity of poly(5,6-epoxy-1-octenamer) increases with the content of trans-С=С bonds in the polymer.

    更新日期:2019-12-11
  • Relative Reactivity of Dicyclopentadiene and 2,3-Dicarbomethoxy-5-norbornene in Metathesis Copolymerization and the Properties of the Copolymer
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    A. A. Lyapkov, G. S. Bozhenkova, N. A. Smirnova, N. I. Prokudina, M. S. Yusubov, F. Verpoort

    In this paper, Fourier transform infrared spectroscopy (FTIR) was applied to examine the metathesis copolymerization of dicyclopentadiene with a mixture of exo,exo- and endo,endo-2,3-dicarbomethoxy-5-norbornene using a Hoveyda-Grubbs II type catalyst. The obtained data allowed us to calculate the monomer reactivity ratios of dicyclopentadiene and the isomers of 2,3-dicarbomethoxy-5-norbornenes. The relative reactivity of dicyclopentadiene was around eight times lower than the reactivity of the isomer mixtures.

    更新日期:2019-12-11
  • Norbornene Addition Polymerization with Catalysts Based on Transition Metal Compounds: 2008–2018
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    D. S. Suslov, M. V. Bykov, O. V. Kravchenko

    This review summarizes the data on the addition polymerization of norbornene catalyzed by various transition metal complexes published over the period of 2008–2018. The interest in the addition polynorbornenes is due to their dielectric, mechanical, and optical properties, which makes them attractive for use in the microelectronic industry and optics. The regularities of polymerization using catalysts based on Ti, Ir, Ni, Pd, and Cu compounds are considered.

    更新日期:2019-12-11
  • Stereoselective synthesis and metathesis polymerization of exo -5-(Pentamethyldisiloxanyl) norbornene
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    M. A. Guseva, D. A. Alentiev, D. I. Gavrilov, E. V. Bermesheva, P. P. Chapala, E. Sh. Finkelshtein, M. V. Bermeshev

    A one-step selective method based on the hydrosilylation of 2,5-norbornadiene with commercially available silanes in the presence of a Pd-catalyst and bulky ligand R-MOP is developed for the synthesis of exo-isomers of silicon-containing norbornenes. This approach leads to the formation of exclusively exo-isomers. The absence of the steps of alkylation with organometallic reagents and photochemical isomerization makes the proposed approach attractive for the targeted design and synthesis of new polymeric materials with the required properties.

    更新日期:2019-12-11
  • Unusual Structural Changes of PIM-1 Polymer Detected by Means of Chromatographic Technique
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    V. E. Shiryaeva, T. P. Popova, A. Yu. Kanateva, A. A. Korolev, A. A. Kurganov

    Changes in retention factor k of light hydrocarbons on PIM-1 stationary phase with an increase of ageing temperature are tested. Varying the ageing temperature from 50 to 200°C causes a slight decrease in solute retention, which, however, changes to strong increase as soon as the ageing temperature exceeds 200°C. An increase of the solute retention factor k means the proportional increase of the Henry equilibrium constant K, which in turn under constant chromatographic conditions probably points out the thermodynamic changes in the structure of PIM-1 which can be caused either by a chemical decomposition or by a structural rearrangement. Due to high chemical stability of PIM-1, an increase of solute retention with thermal ageing is a consequence of structural rearrangements of polymeric chains, resulting in more adapted adsorption sites. At the same time, accessibility of the adsorption sites decreases as it is indicated by the reduction of column efficiency and diffusion coefficients.

    更新日期:2019-12-11
  • Iridium-Containing Polymers Based on Norbornene and 7-Oxa-norbornene Monomers: Synthesis and Photophysical and Biological Properties
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    L. N. Bochkarev, E. O. Platonova, S. A. Lermontova, L. G. Klapshina, A. N. Konev, G. A. Abakumov

    Polymers containing oligoether groups, amino acid fragments, and luminophore complexes of iridium(III) in side chains are synthesized by metathesis polymerization. The photophysical properties of the compounds obtained are studied. The iridium-containing copolymers show intense green, blue-green, and red photoluminescence, and the color is determined by the nature of the iridium(III) complexes contained in polymeric emitters. Polymeric products are soluble in water and form micelles with average sizes of 19–54 nm. The cytotoxicity of the polymers with respect to A431 human epidermoid carcinoma cells is determined.

    更新日期:2019-12-11
  • Synthesis, Structure and Properties of Poly(1-trimethylsilyl-1-propyne) Obtained with NbBr 5 - and TaBr 5 -Based Catalytic Systems
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2019-11-01
    S. M. Matson, A. A. Kossov, V. P. Makrushin, I. S. Levin, N. A. Zhilyaeva, E. G. Litvinova, V. S. Khotimskiy

    In this work, the polymerization of 1-trimethylsilyl-1-propyne [TMSP] using catalytic systems based on pentabromide Nb(V) and Ta(V) with organometallic cocatalysts Ph3Bi, Ph4Sn, Bu4Sn, Ph3SiH, and Et3SiH was investigated. The use of NbBr5-based catalytic systems has strongly marked cis-stereospecificity and gives highly cis-enriched poly(1-trimethylsilyl-1-propyne) [PTMSP] (content of cis-units above 70%), whereas the use of TaBr5-based catalytic systems leads to the formation of PTMSP with mixed cis-/trans-composition (content of cis-units from 50 to 65%).With increasing cis-content, solvent resistance of PTMSP increases significantly. PTMSP with a content of cis-units above 70% obtained on NbBr5-containing systems in cyclohexane acquires resistance to aliphatic and aromatic hydrocarbons, and cis-regular PTMSP obtained on NbBr5-based systems in toluene is totally insoluble in any of the organic solvents. The results of wide-angle X-ray diffraction indicate an increase in the packing density of the polymer during the transition from a mixed configuration to a cis-regular one. Durable PTMSP film membranes exhibit ultra-high permeability coefficients for individual gases (e.g., \({{P}_{{{{{\text{O}}}_{{\text{2}}}}}}}\) = 8500–11000 barrer, \({{\alpha }_{{{{{\text{O}}}_{{\text{2}}}}{\text{/}}{{{\text{N}}}_{{\text{2}}}}}}}\) = 1.5–1.9). According to the low-temperature Ar sorption, PTMSP synthesized with NbBr5- and TaBr5-based catalytic systems has high BET surface areas in the range of 870–1050 m2/g, high intrinsic microporosity, and higher gas permeability coefficients of PTMSP correlate with BET surface area growth.

    更新日期:2019-12-11
  • The Behavior of Amphiphilic Molecular Brushes with Polyimide Backbone and Poly(methyl methacrylate) and Polystyrene Side Chains in the Vicinity of Θ Point
    Polym. Sci. Ser. C (IF 1.296) Pub Date : 2018-11-29
    A. P. Filippov, A. S. Krasova, E. B. Tarabukina, T. K. Meleshko, A. V. Yakimansky, S. S. Sheiko

    The behavior of amphiphilic molecular brushes in the vicinity of the Θ point has been studied by the methods of molecular hydrodynamics and optics upon variation of temperature. As objects of investigation, graft copolymers with polyimide main chain and poly(methyl methacrylate) and polystyrene side chains were chosen. The samples studied differed in the backbone and side chain lengths at a similar degree of grafting. The molecular mass of the samples under investigation was varied in a sevenfold range. For comparison, linear poly(methyl methacrylate) and polystyrene have been studied. It has been shown that the behavior of molecular brushes and linear polymers in the vicinity of the Θ point differs significantly. A more rapid gain in intrinsic viscosity of the solutions of graft copolymers in the vicinity of the Θ point is explained by the simultaneous increase in the volume of macromolecules and in their shape asymmetry.

    更新日期:2019-12-11
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