The synthesis and gas permeation properties of addition-type poly­(3,3-bis­(trimethylsilyl)­tricyclononene-7) (PTCNSi2g) are first reported. High molecular weight PTCNSi2g was obtained via addition polymerization of 3,3-bis­(trimethylsilyl)­tricylononene-7 on a Pd-containing catalyst. It possessed a BET surface area as high as 790 m2/g. This new polymer is distinguished by extra high gas permeability and solubility controlled permeation of hydrocarbons. Positron annihilation lifetime spectroscopy revealed extremely large size of free volume elements (8.3 Å). PTCNSi2g is a promising membrane material for separation of natural gas.

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In recent years, the development of methods for the synthesis of Mo2C for catalytic application has become especially important. In this work a series of Mo2C samples was synthesized by thermal decomposition of molybdenum blue xerogels obtained using ascorbic acid. The influence of the molar ratio reducing agent/Mo [R]/[Mo] on morphology, phase composition and characteristics of the porous structure of Mo2C has been established. The developed synthesis method allows the synthesis to be carried out in an inert atmosphere and does not require a carburization step. The resulting molybdenum carbide has a mesoporous structure with a narrow pore size distribution and a predominant pore size of 4 nm.

Stable molybdenum blue nanoparticles dispersions were synthesized using ammonium heptamolybdate and ascorbic acid. The effect of molar ratios of reducing agent/Mo and acid/Mo on the speed of formation and stability of the disperse system has been demonstrated. The particles were characterized by UV/vis, infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, and dynamic light scattering (DLS) methods. The X-ray photoelectron spectroscopy (XPS) method confirmed the presence of reduced MoV in the structure of molybdenum oxide nanoclusters, the proportion of which was 30%.

In this work the authors report the preparation of new addition copolymers based on 3‐trimethylsilyltricyclononene‐7 (TCNSi1) and 3,3,4‐tris(trimethylsilyl)tricyclononene‐7 (TCNSi3). A number of high molecular weight copolymers are synthesized with the content of TCNSi3 units from 5 up to 20 mol% in the presence of catalyst Pd(OAc)2/[Ph3C]+[B(C6F5)4]− with the yields of 50%–80%. The obtained copolymers are amorphous. They possess large free volume elements (R 3/R 4) based on positron annihilating lifetime spectroscopy analysis and Brunauer–Emmett–Teller surface area up to 640 m2 g−1. Permeability coefficients of the obtained copolymers are determined for a wide range of gases He, H2, O2, N2, CO2, CH4, C2H6, C3H8, n‐C4H10. The correlation between the content of TCNSi3 units and gas permeation parameters of the resulting copolymers is explored. It is found that the introduction of TCNSi3 moieties results in the rise in gas permeability of the corresponding copolymers. Moreover, increase in TCNSi3 content in the copolymer leads to an increase of gas permeability.