Synthesis and Gas-Transport Properties of Poly(1-trimethylsilyl-1-propyne)- and Poly(4-methyl-2-pentyne)-Based Chlorinated Polyacetylenes for Membrane Separation of Carbon Dioxide

Abstract

This work is devoted to the chemical modification of the polymers of 1,2-disubstituted acetylenes for the creation of gas-separation membranes possessing enhanced stability to aliphatic hydrocarbons and CO 2 selectivity. The feasibility of obtaining polyacetylenes containing chlorine atoms in the side substituents of poly(1-trimethylsilyl-1-propyne) (PTMSP) and poly(4-methyl-2-pentyne) (PMP) by radical chlorination with N-chlorosuccinimide has been shown. The reaction has been carried out under mild conditions to minimize the possibility of polymer degradation and other side reactions. The obtained polymers exhibit good mechanical and film-forming properties as well as high thermal stability. Chlorinated PTMSP possesses enhanced stability to alicyclic and aliphatic C 5-C 12 hydrocarbons. It has been shown that in the case of introduction of chlorine into the structure of PTMSP and PMP, the CO 2 /N 2 and CO 2 /CH 4 selectivities increase, with the high level of permeability being retained.

Ionic Mobility in Ion-Exchange Membranes

“…Membrane technologies are widely demanded in a number of modern industries. They are used for gas separation [ 1 , 2 , 3 ], water purification [ 4 , 5 , 6 , 7 ], purification of pharmaceutical drugs and biological fluids [ 8 ]. The number of applications of membrane technologies in the chemical and petrochemical industries [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ], modern energy [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], and sensorics [ 24 , 25 , 26 , 27 ] has significantly increased.…”

Revealing the Surface Effect on Gas Transport and Mechanical Properties in Nonporous Polymeric Membranes in Terms of Surface Free Energy

“…For the first time in membrane science, this novel study represents the relation of surface roughness of nonporous polymeric membranes with their gas separation and mechanical properties in terms of surface free energy. The most widely used polymeric membranes are made based on commercially available polyimide, polyurethane, , cellulose acetate or triacetate, , polyamide, Pebax 1657, , poly­(vinyl alcohol), polysulfone, poly­(vinylidene fluoride), polyacetylene, and several other polymers . From this variety of polymers, three ones differing in chain rigidity were selected, namely, polysulfone (PSU), cellulose triacetate (CTA), and poly­(vinyl alcohol) (PVA).…”

Applications of Polyacetylene Derivatives in Gas and Liquid Separation

“…The selectivity was doubled and the permeability was not reduced much, which was closer to the upper limit curve in the Robeson diagram than the original PTMSP. On the basis of the previous introduction of bromine and fluorine atoms, Kossov et al [ 39 ] successfully improved the selectivity to CO 2 by introducing chlorine atoms on the side chains of PTMSP and PMP, but the permeability was reduced compared with the initial polymer. This is consistent with Robeson’s law, that is, there is a “trade-off” relationship between permeability and selectivity.…”