Effect of carbonyl group on sorption and transport properties of gases in polymeric membranes
The object of this work was to search for the relationships between the carbonyl group density and gas transport properties in the membrane. The intrinsic gas transport properties: permeation, diffusion, and sorption in a series of dense membranes with various carbonyl group densities were investigated. The pure He, O2, N2,and CO2 permeability were measured using a temperature-controlled permeation analyzer. The sorption isotherms were obtained using a Cahn 1000 microbalance sorption cell. The PMMA, PC, and COC membranes have similar He permeability, and the PPO membrane has very high He permeability. The permeability of these four membranes presents a parallel trend with their fraction free volume. The solubilities of these membranes increase with increasing gas condensability in the order of CO2, 02, and N2. In this study, a direct relationship was found between the carbonyi group density and Langmuir affinity constant. Furthermore, dependence of the fractional free volume on the membrane Langmuir capacity constant was observed. Consequently, we can conclude that solubility is improved by increasing the carbonyl group density on the polymer chains of various polymers and this effect becomes more pronounced with increasing penetrant eondensability. It was found that the carbonyl group in the membrane decreased the gas diffusivity because it might have a strong interaction with the penetrant gas molecules.
Chien-Chieh Hu Ywu-Jang Fu Kueir-Ram Lee Juin-Yih Lai
Department of Chemical Engineering,Nanya Institute of Technology,Chung Li,32034,Taiwan Department of Biotechnology,Vanung University,Chung-Li 32023,Taiwan R&D Center for Membr.Technol.and Department of Chemical Engineering,Chung Yuan University Chung-Li 3
国际会议
5th East-Asian Polymer Conference(第5届东亚高分子学术研讨会)
上海
英文
247-248
2008-06-03（万方平台首次上网日期，不代表论文的发表时间）