ИСТИНА

There are a number of challenges related to the recovery of large organic molecules from mixtures with smaller molecules. For example, separation of alcohols from diluted aqueous solutions by pervaporation, C3 + hydrocarbons from natural gas and organic vapors from air. These problems can be solved using sorption-selective membrane materials, such as silicone rubbers (especially PDMS). These have stable separation performance over time, so they are real industrial application. Polysilmethylenes significantly more selective on large organic components, but have poor film-forming properties. Polydimethylalkylenesiloxanes containing as a main chain silmethylenes and siloxane fragments are hybrid materials that can combine membrane performance stability and high selectivity. Cationic and anionic polymerization of 1,1,3,3-tetramethyl-2-oxa-1,3-disilacyclopentane (I) and 1,1,3,3-tetramethyl-2-oxa-1,3-disilacyclohexane (II) synthesized α,ω-dihydroxypolydimethylsildimethylene (III)- and α,ω- dihydroxypolytrimethylsildimethylene (IV)-dimethylsiloxanes. Via crosslinking condensation of tetraethoxysilane and terminal hydroxyl groups of III and IV flat membranes MI and MII with stable mechanical properties are formed. Gas transport properties of these membranes for methane and butane are investigated. It was shown that synthesized materials MI and MII have a higher ideal selectivity of butane/methane compared to PDMS at high permeability coefficients (7800 and 6600 barrier respectively). Shown to increase the selectivity of butane/methane is achieved due to the high coefficients of butane solubility in the membrane materials.