Gas permeation parameters and other physicochemical properties of a polymer of intrinsic microporosity: Polybenzodioxane PIM-1
Gas permeation parameters and other physicochemical properties of a polymer of intrinsic microporosity: Polybenzodioxane PIM-1
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DOI：
10.1016/j.memsci.2008.09.010
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发表时间：
2008-12-01
影响因子：
9.5
通讯作者：
Shantarovich, Victor
中科院分区：
文献类型：
--
作者：
Budd, Peter M.;McKeown, Neil B.;Shantarovich, Victor
研究了一种新型的本征微孔聚合物（PIM-1）的气体渗透性能、热力学性质和自由体积。使用气相色谱法和气压法测量气体渗透率。用反相气相色谱法（IGC）研究了蒸气的吸附。此外，还利用正电子湮没寿命谱（帕尔斯）研究了该聚合物的自由体积。PIM-1的一个不寻常的性质是透气性和自由体积对膜流延方案的非常强的敏感性。在膜制备过程中与水接触导致相对低的气体渗透性（P（O-2）= 120 Barrer），而用甲醇浸泡导致气体渗透性的强烈增加（P（O-2）= 1600 Barrer），几乎没有快速老化（渗透性降低）的证据，这对于高渗透性聚合物是典型的。对于各种气体对（O-2/N-2、CO2/CH 4、CO2/N-2），罗伯逊图上的数据点位于上限线上方。因此，观察到渗透性和选择性的非常有吸引力的组合。IGC表明，这种聚合物是区别于迄今为止研究的所有聚合物中的最大溶解度系数。PIM-1的自由体积包括相对大的微腔（R = 5埃），并且帕尔斯和IGC方法的结果是合理一致的。(C)2008 Elsevier B. V.保留所有权利。
A detailed study of gas permeation, thermodynamic properties and free volume was performed for a novel polymer of intrinsic microporosity (PIM-1). Gas permeability was measured using both gas chromatographic and barometric methods. Sorption of vapors was studied by means of inverse gas chromatography (IGC). In addition, positron annihilation lifetime spectroscopy (PALS) was employed for investigation of free volume in this polymer. An unusual property of PIM-1 is a very strong sensitivity of gas permeability and free volume to the film casting protocol. Contact with water in the process of film preparation resulted in relatively low gas permeability (P(O-2) = 120 Barrer), while soaking with methanol led to a strong increase in gas permeability (P(O-2) = 1600 Barrer) with virtually no evidence of fast aging (decrease in permeability) that is typical for highly permeable polymers. For various gas pairs (O-2/N-2, CO2/CH4, CO2/N-2) the data points on the Robeson diagrams are located above the upper bound lines. Hence, a very attractive combination of permeability and selectivity is observed. IGC indicated that this polymer is distinguished by the largest solubility coefficients among all the polymers so far studied. Free volume of PIM-1 includes relatively large microcavities (R = 5 angstrom), and the results of the PALS and IGC methods are in reasonable agreement. (C) 2008 Elsevier B.V. All rights reserved.