Organic Vapor Separation with Super-Glassy Polymer Membranes

本研究将研究渗透性和选择性， 各向同性聚合物膜的气体传输， 聚（三甲基硅基丙炔）（PTMSP;<$C（CH 3）=C（SiCH 3）3）n）。 先前对PTMSP膜的研究表明， 由于它们的自由体积大， 气体分子通过膜是非常大的，这 导致非常高的透气性。 高 渗透性伴随着相对低的选择性 (i.e.一个物种的通量与另一个物种的通量之比 其他）。 这种缺乏选择性的情况可以再次归因于 大的自由体积尺寸，这有利于容易通过 各种大小的分子。 因此，迄今为止， 膜在气体分离中没有实用价值。 然而，研究指出，选择性 通过使纯气体穿过膜来测量， 取相同驱动条件下的流量比。 最近的实验表明，该膜表现出 共渗透的选择性：在特定的实验中， MTR表明在正丁烷中对正丁烷的选择性为27：1。 丁烷/甲烷混合物，24 oC。 研究结果 将通过研究纯天然气和混合天然气的运输， PTMSP与一系列永久性气体如甲烷或空气， 和密切相关的有机溶剂蒸气（CCl 4，CF 4，a 一系列的氟利昂和碳氢化合物蒸汽，如丁烷 如果成功的话，这项研究将导致膜 它可以从甲烷中分离丁烷（在 天然气工业）和来自空气的有机蒸气（ 在许多环境问题上的重要分离）。

This study will examine the permeability and selectivity for gas transport of isotropic polymeric membranes made of poly(trimethyl silylpropyne) (PTMSP; ıC(CH3)=C(SiCH3)3!n). Previous research on PTMSP membranes have shown that because of their large free volume, the solubility and diffusivity of gas molecules through the membrane is very large, and this results in a very high gas permeability. The high permeability is accompanied by relatively low selectivity (i.e. the ration of the flux of one species to that of the other). This lack of selectivity can be attributed again to the large free volume size which facilitates the easy passage of molecules of all sizes. Consequently, to date PTMSP membranes have not been of practical value in gas separations. The research points out, however, that the selectivity has been measured by passing pure gases through the membrane and taking the flux ratio under identical driving conditions. Recent experiments have shown that the membrane exhibits selectivity in co-permeation: In particular experiments at MTR demonstrate a 27:1 selectivity on n-butane in an n- butane/methane mixture at 24oC. The result of this research will be built by studying pure and mixed gas transport in PTMSP with a series of permanent gases such as methane or air, and closely related organic solvent vapors (CCl4, CF4, a series of freons and with hydrocarbon vapors such as butane and pentane if successful, the research will lead to membranes which can separate butane from methane (important in the natural gas industry), and organic vapors from air (an important separation in many environmental concerns).