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A comprehensive interdisciplinary study is performed for 12 polymers promising for the fabrication of membranes for extracorporeal membrane oxygenation based on them by methods of gas permeability, wetting, piezoelectric microweighing, and direct biomedical methods for determining hemocompatibility of whole blood from healthy donors. It is found that trimethylsilyl-substituted polytricyclononene, polyhexafluoropropylene, and semicrystalline polyphenylene oxide are the best polymer materials for the diffusion membranes of oxygenators. It is shown that traditional approaches that associate the surface properties of polymers (water wettability, plasma protein adsorption, energy characteristics of surfaces) with their hemocompatibility do not provide precise correlations with the biomedical methods based on the analysis of the changes in the shape of blood cells as a result of adhesion on the surface of the polymer. The complexity of the mechanism of interaction of the surface of polymers with blood also does not allow for clear structure–property correlations traditional for membrane gas separation. The directions of further research in this area are defined.

Addition polynorbornenes are the promising class of polymers for macromolecular design of various engineering polymers. This work has shown for the first time the fundamental possibility to obtain addition polynorbornenes in the presence of catalytic systems based on Pd(0) complexes activated by organic cocatalysts (aryl halides). Addition polymerization of norbornene has been studied in the presence of different cocatalysts, which allowed one to assess the effect of cocatalyst nature on the activity of the catalytic system.

We studied the addition polymerization of readily available bifunctional norbornene derivatives, 5-alkylidene-2-norbornenes, in the presence of modified Pd complexes with N-heterocyclic carbene lig...

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).

Previously undescribed norbornene monomer 3,3,4-trifluoro-4-perfluorohexyltricyclononene-7 is synthesized by the [2+2+2] cycloaddition reaction. The monomer is involved in the ring-opening polymerization metathesis in the presence of the first-generation Grubbs catalyst to give rise to the amorphous, glassy unsaturated polymer. The gas-transport properties of the metathesis polymer is studied, the gas permeability and diffusion coefficients for a wide range of gases (He, H2, O2, N2, CO2, CH4) are determined, and the solubility coefficients of gases in this polymer are calculated.

An approach to activating Pd-complexes without using additives such as Lewis acids has been developed for addition polymerization of norbornenes. Aryl iodides and aryl diazonium salts were efficiently applied as cocatalysts to Pd(0)- and Pd(2+)-complexes. The developed systems catalyzed polymerization of norbornenes containing bulky and polar functional groups both in an inert atmosphere and air resulting in soluble and high-molecular-weight saturated polymers.

Polynorbornenes represent a fruitful class of polymers for structure&ndash, property study. Recently, vinyl-addition polynorbornenes bearing side groups of different natures were observed to exhibit excellent gas permeation ability, along with attractive C4H10/CH4 and CO2/N2 separation selectivities. However, to date, the gas transport properties of fluorinated addition polynorbornenes have not been reported. Herein, we synthesized addition polynorbornene with fluoroorganic substituents and executed a study on the gas transport properties of the polymer for the first time. A norbornene-type monomer with a C6F5 group, 3-pentafluorophenyl-exo-tricyclononene-7, was successfully involved in addition polymerization, resulting in soluble, high-molecular-weight products obtained in good or high yields. By varying the monomer concentration and monomer/catalyst ratio, it was possible to reach Mw values of (2.93&ndash, 4.35) &times, 105. The molecular structure was confirmed by NMR and FTIR analysis. The contact angle with distilled water revealed the hydrophobic nature of the synthesized polymer as expected due to the presence of fluoroorganic side groups. A study of the permeability of various gases (He, H2, O2, N2, CO2, and CH4) through the prepared polymer disclosed a synergetic effect, which was achieved by the presence of both bulky perfluorinated side groups and rigid saturated main chains. Addition poly(3-pentafluorophenyl-exo-tricyclononene-7) was more permeable than its metathesis analogue by a factor of 7&ndash, 21, or the similar polymer with flexible main chains, poly(pentafluorostyrene), in relation to the gases tested. Therefore, this investigation opens the door to fluorinated addition polynorbornenes as new potential polymeric materials for membrane gas separation.

The synthesis and gas-transport properties of new metathesis-type polynorbornenes bearing fluoroorganic side groups are reported. The necessary monomers, fluorosubstituted exo-norbornene derivatives (exo-tricyclononenes), were obtained using one-step method based on stereo- and regioselective [2 + 2+2]-cycloaddition of quadricyclane and fluoroalkenes. A set of high molecular weight polymers with different side groups were prepared from the synthesized F-substituted exo-tricyclononenes over the 1-st generation Grubbs catalyst. Permeability and diffusion coefficients of various gases (He, H2, O2, N2, CO2, CH4) in these poly-exo-tricyclononenes were determined for the first time and new relationships between polymer structure and gas permeability were established. Metathesis poly-exo-tricyclononene bearing four CF3-groups in each monomer unit displayed the highest gas permeability for the tested gases among metathesis polynorbornenes with F-organic substituents reported so far.

New high-performance catalytic systems based on Pd N-heterocyclic carbene complexes for the selective addition polymerization of 5-ethylidene-2-norbornene (ENB) were proposed. With these catalysts, polymerization can be conducted at unprecedentedly high monomer/catalyst ratio (up to 5 × 105/1) and gives high-molecular-weight soluble polymers with good film-forming properties. Varying the polymerization conditions (reaction temperature, monomer and catalyst concentrations, monomer/Pd ratio) makes it possible to prepare soluble ENB-based addition polymers with specified molecular weights in reasonable yields.

Structure-property study of polynorbornenes for low dielectric permittivity materials was performed. Dielectric properties of various polynorbornenes bearing F-, Si- and alkenyl-side groups were investigated. The incorporation of both fluoroorganic- and Me3Si-groups as side substituents was found to be a fruitful tool to tune dielectric properties and to obtain polymeric materials with low values of dielectric relative permittivity (hereinafter dielectric permittivity) and the dissipation factors. Addition polynorbornenes with Me3Si- or alkenyl-side groups disclosed dielectric permittivity in the range of 2.07–2.34. Polynorbornenes containing fluouroorganic groups exhibited dielectric permittivity as low as 1.94–2.78. To the best of our knowledge, the achieved values of dielectric permittivity are the lowest ones among published for polynorbornenes. The investigated polymers also exhibited low or moderate values of the dissipation factor. The obtained results are considered and discussed along with the data of wide-angle X-ray diffraction, positron annihilating lifetime spectroscopy, low temperature nitrogen adsorption/desorption investigations.

Herein the synthesis of a new series of fluorine containing tricyclononenes using [2σ+2σ+2π]-cycloaddition of quadricyclane with fluorine containing alkenes is described. According to the experiment the reactivity of fluorine containing alkenes in [2σ+2σ+2π]-cycloaddition reaction was established. The obtained cycloadducts were successfully involved in ring-opening metathesis polymerization on Ru-based catalytic systems. The obtained polymers were glassy and amorphous. The investigation of gas-transport properties of the new materials with improved selectivity towards different pairs of gases was executed.Herein the synthesis of a new series of fluorine containing tricyclononenes using [2σ+2σ+2π]-cycloaddition of quadricyclane with fluorine containing alkenes is described. According to the experiment the reactivity of fluorine containing alkenes in [2σ+2σ+2π]-cycloaddition reaction was established. The obtained cycloadducts were successfully involved in ring-opening metathesis polymerization on Ru-based catalytic systems. The obtained polymers were glassy and amorphous. The investigation of gas-transport properties of the new materials with improved selectivity towards different pairs of gases was executed.