CO2 plasticization and physical aging of perfluorocyclobutyl polymer selective layers

Physical aging of glassy perfluoropolymers in thin film composite membranes. Part I. Gas transport properties

“…TFC membranes were initially evaluated at feed pressures of 50, 100 and 150 psig using CH 4 , N 2 and H 2 to verify that the membranes were defect-free. Pure-gas CO 2 was tested at 50 psig to avoid the CO 2 plasticization, which affects the aging behavior [12,41]. After testing, the TFC membranes were kept inside the permeation cell at room temperature in the air.…”

“…The decrease of gas permeance with time in thin film polymers has been widely documented for a broad range of glassy polymers such as polysulfone [5][6][7]10], poly(phenylene oxide) [6,10], Matrimid ® [6,7,10], 6FDA-durene [11], perfluorocyclobutyl (PFCB) polymers [12], poly(1trimethylsilyl-1-propyne) (PTMSP) [13], and polymers of intrinsic microporosity (PIMs) [8,[13][14][15][16]. The physical aging also increases gas selectivity that benefits from the favorable diffusivity selectivity.…”

Ring-Forming Polymerization toward Perfluorocyclobutyl and Ortho-Diynylarene-Derived Materials: From Synthesis to Practical Applications

“…The versatility of the aryl ether linkages, presence of thermally stable aromatic rings, and improved processability due to the PFCB ring make the utility of PFCB polymers promising in many practical applications [ 9 , 11 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ]. This section summarizes several important uses of PFCBs, such as high-performance protective coatings, membrane layers, dielectrics, and optical materials.…”

“…They are generally prepared by free radical mediated [2 + 2] thermal cyclopolymerization of functional aryl trifluorovinyl ether (TFVE) monomers at temperatures above 150 °C without using any catalysts or initiators ( Scheme 1 a) [ 12 , 18 , 19 ]. The cycloaddition of the fluoroolefins produces fluorinated cyclobutane rings, giving an overall amorphous PFCB polyaryl ethers with good solubility and solution processability for an array of new applications [ 9 , 11 , 12 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ]. In the past decades, our group has been dedicated to the synthesis and applications of tailored PFCB polymers [ 12 , 20 , 44 , 45 , 46 , 47 , 48 , 49 ].…”

Effect of dense CO2 on polymeric reverse osmosis and nanofiltration membranes and permeation of mixtures of macauba oil (Acrocomia aculeata) and CO2

“…Higher fluxes obtained after CO 2 in this supercritical condition suggest that the polymeric matrix is changing, which is probably due to swelling and/or plasticisation of the polymer by CO 2 . When CO 2 is subjected to higher pressures and temperatures its capacity of interacting with the polymer gets stronger, which may lead to more severe changes in membrane structure, resulting in more pronounced swelling or plasticisation of the polymer, as a result for the higher mobility of the polymeric chain [9,17]. When the membranes were made of polyamide (NF270, ORAK and BW30) they present carbonyl and amino groups only partially crosslinked within its structure with a certain tendency to present hydrogen bonding.…”