Solubility and partial molar volume of carbon dioxide and ethane in crosslinked poly(ethylene oxide) copolymer

Abstract

Experimental solubility and sorptive dilation data are reported for carbon dioxide and ethane in a crosslinked poly(ethylene oxide) (XLPEO) rubbery copolymer. Five different temperatures (253 ≤ T(K) ≤ 308) were considered, with a maximum gas pressure of 2.09 MPa (20.6 atm). The polymer was prepared by photopolymerization of a solution containing 70 wt % poly(ethylene glycol) methyl ether acrylate (PEGMEA) and 30 wt % poly(ethylene glycol) diacrylate (PEGDA). Sorption isotherms were described by the Flory‐Huggins model. For each gas, the Flory‐Huggins interaction parameter was a decreasing function of temperature and did not show a composition dependence. Dilation and sorption data were combined to calculate the partial molar volume (PMV) of the gases in the polymer, which was an increasing function of temperature. Based on a comparison with literature data for a XLPEO homopolymer prepared from pure PEGDA over the same range of operating conditions, an effect of the network composition on both gas solubility and PMV was found. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 456–468, 2010

High performance membranes based on ionic liquid polymers for CO2 separation from the flue gas

“…Therefore, the overall enthalpy of sorption will be more negative and thus favor gas sorption. 45 According to Table 2, a poly(RTIL) with a longer N-alkyl group has a higher free volume than those with shorter N-alkyl groups. Hence, the gas solubility increases in the order of poly Table 3, the pristine poly(RTIL)s exhibit (1) lower CO 2 solubilities, (2) smaller CO 2 -N 2 solubility selectivities compared with [emim][dca] and (3) decreasing CO 2 -N 2 solubility selectivities with increase in the lengths of N-alkyl group.…”

“…Therefore, the overall enthalpy of sorption will be more negative and thus favor gas sorption. 45 According to Table 2, a poly(RTIL) with a longer N-alkyl group has a higher free volume than those with shorter N-alkyl groups. Hence, the gas solubility increases in the order of poly(…”

Modeling Gas and Vapor Sorption and Swelling in Triptycene-Based Polybenzoxazole: Evidence for Entropy-Driven Sorption Behavior

“…As reported by Ribeiro and Freeman, CO 2 partial molar volumes in rubbery PEO follow a similar qualitative trend as a function of temperature. 51,52 However, because rubbery polymers do not contain preexisting free volume holes, the total volume change with CO 2 concentration is expected to be much more pronounced than in glassy polymers. This hypothesis is confirmed by the fact that the CO 2 partial molar volumes in PEO are 1 order of magnitude larger than in TPBO.…”

“…This hypothesis is confirmed by the fact that the CO 2 partial molar volumes in PEO are 1 order of magnitude larger than in TPBO. 51,52 At higher penetrant concentrations, the TPBO free volume sites reach saturation; therefore, matrix swelling is needed to accommodate additional penetrant molecules. As expected, CO 2 partial molar volumes markedly increase with increasing concentration.…”

Equation of State Modeling of the Solubility of CO2/C2H6 Mixtures in Cross-Linked Poly(ethylene oxide)

“…In this study, the solubility of C 2 H 6 /CO 2 mixtures in cross-linked poly­(ethylene oxide) (XLPEO) is modeled at various temperatures, pressures, and gas compositions. − PEO-based membranes are of interest for CO 2 removal from light gases, due to their high solubility selectivity toward CO 2 . Therefore, accurate measurement and modeling of the solubility of CO 2 -containing mixtures in such materials is of interest.…”