A defect-free polyether sulfone (PES) asymmetric membrane was prepared by a one-step phase inversion process and applied gas separation process in this article. The morphology of the PES asymmetric membrane formed via phase inversion that was correlated with the solvent composition, evaporation environment, coagulation bath, and so forth. The results reveal two kinds of coagulation phenomena that lead to different membrane structures and separation results. An instantaneous coagulation PES membrane formed a finger-like structure within the membrane, and a delayed coagulation PES membrane resulted in a sponge-like structure membrane. The selectivity of O₂/N₂ for membrane gas separation indicated that the asymmetric membranes prepared via a one-step process in this study were defect-free. Using the phase inversion method to fabricate asymmetric membranes improved the low permeability characteristic of glassy polymers. The maximum permeability of CO₂ for the PES asymmetric membrane in the text can approach 30 Barrer. The results of gas separation for the sponge-like PES membrane showed that the selectivity of O₂/N₂ and CO₂/N₂ was 7.1 and 35.6, respectively. This research showed that a PES asymmetric membrane was fabricated via a one-step process without further defect repair and was applied effectively for CO₂ membrane gas separation.

中文翻译：

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相转化法研究聚醚砜不对称膜的透气性能

本文采用一步相转化法和气体分离法制备了一种无缺陷的聚醚砜（PES）不对称膜。PES非对称膜的形态通过相转化形成，与溶剂组成、蒸发环境、凝固浴等相关。结果揭示了导致不同膜结构和分离结果的两种混凝现象。瞬时凝固PES膜在膜内形成指状结构，延迟凝固PES膜形成海绵状结构膜。_{O 2} /N ₂的选择性用于膜气体分离的研究表明，在本研究中通过一步法制备的不对称膜是无缺陷的。采用相转化法制备不对称膜改善了玻璃态聚合物的低渗透特性。文中PES不对称膜的CO ₂最大渗透率可以接近30 Barrer。海绵状PES膜的气体分离结果表明，O ₂ /N ₂和CO ₂ /N ₂的选择性分别为7.1和35.6。该研究表明，PES非对称膜通过一步工艺制造，无需进一步修复缺陷，可有效应用于CO ₂膜气体分离。