Synthesis and Gas Permeability of PDMS/PEO Alternately Grafted Aromatic Polyamides

Abstract

The syntheses of novel graft copolyamides containing both of poly( ethylene oxide) (PEO) and polydimethylsiloxane (PDMS) in the side chains were carried out by a macromonomer method, in order to develop a new functional membrane material which were expected to possess the high permeability of PDMS and the functionality of PEO-metal complex. For this purpose, 3,5-bis(4-carboxyphenyloxy)phenyloxy-terminated PEO (BCPP-PEO) and 3,5-bis(4aminophenoxy)benzyloxypropyl-terminated PDMS (BAPB-PDMS) were synthesized as macromonomers. The polycondensations of BCPP-PEO and BAPB-PDMS yielded the desired PDMS/PEO alternately grafted aromatic polyamide (P A-g-SE). Copolymer membranes were prepared by solvent casting method, and the gas permeability of these membranes was evaluated. As a result, P A-g-SE membrane exhibited the higher gas permeability than PEO-grafted polyamide membrane (P A-g-PEO). Furthermore, the selectivity of olefin gas through the membrane was effectively advanced by the addition of Ag ion to the copolymer membrane.

Pervaporation Membrane Exhibiting High Biocompatibility Based on PDMS/PEO Alternately Grafted Aromatic Polyamide

“…However, the gas permeability coefficients of these membranes were lower than those of PDMS crosslinked membrane, because the gas permeations through the copolymer membrane were prevented by the strong interaction of amide group or PEO segments. Actually, in the case of PA-g-PEO membrane, very low gas permeability was observed as described in our previous paper [2]. From these results, it was suggested that the gas permeability corresponded to the diffusivity in the membrane.…”

“…The synthetic procedures of macromonomers, BAPB-PDMS and BCPP-PEO, were described in our previous papers [1,2]. Anhydrous 1-methyl-2pyrrolidinone (NMP) was purchased from Aldrich Co., Ltd. Other chemical reagents were used as received.…”

“…PA-g-PDMS and PA-g-PEO were synthesized according to the procedure described in our previous paper [2], and the precipitated polymers were dissolved in NMP and N,N-dimethylformamide (DMF), respectively. Then, the NMP and DMF solutions were cast on a polytetrafluoroethylene sheet, and the solvent was evaporated at 90℃ for 48 h to form a PA-g-PDMS and PA-g-PEO membranes.…”

“…In our previous work, PDMS grafted aromatic polyamide (PA-g-PDMS) was prepared by polycondensation of 3,5-bis(4-aminophenoxy)benzyloxypropyl-terminated PDMS macromonomer (BAPB-PDMS) with terephthaloyl chloride, the membrane of which exhibited the high gas and liquid permeability with a high durability derived from the main chain component [1]. Furthermore, PEO/PDMS alternately grafted aromatic polyamide (PA-g-SEa) was prepared from the 3,5-bis(4-carboxylphenyloxy)phenyloxy-terminated PEO macromonomer (BCPP-PEO) and BAPB-PDMS, in order to develop a new functional membrane material [2]. As a result, the gas permeability coefficients of PA-g-SEa membrane were similar to PA-g-PDMS membrane.…”

Poly(ethylene glycol) and poly(dimethyl siloxane): Combining their advantages into efficient CO2 gas separation membranes

“…The strategy to combine the beneficial properties of highly permeable polymers, such as PDMS, and polyethers (especially PEG) in one single membrane has also been obtained by copolymerization of these moieties in one (block) copolymer. Examples containing PDMS and PEG [35][36][37], PPG [37,38] and PTMG [37,39] polyethers have been reported in literature. Park et al [37] showed that the copolymerization of small amounts of PDMS in polyurethane-polyether block copolymers could increase CO 2 permeability as well as selectivity.…”