Polymeric gas separation membranes are a viable solution to mitigate greenhouse gas emissions directly linked to global warming due to their environment-friendly synthetic process and low cost. Poly(vinyl alcohol) (PVA) synthesized via non-petroleum routes is an eco-friendly material with several advantages for membrane applications such as good film-forming properties, good compatibility, and water solubility. Despite these benefits, the gas barrier property of PVA prevents its application in gas separation membranes. Therefore, we synthesized a graft copolymer consisting of PVA main chains and poly(oxyethylene methacrylate) (POEM) side chains via one-pot free radical polymerization and applied it to a highly CO₂ permeable thin film composite membrane. Synthesis of the PVA-g-POEM graft copolymer was confirmed by Fourier transform infrared and proton nuclear magnetic resonance spectroscopy. X-ray diffraction and differential scanning calorimetry analyses revealed that the crystallinity of PVA-g-POEM decreased gradually with increasing POEM content, with the PVA-g-POEM graft copolymer becoming amorphous at a POEM content of 64 wt%. The composite membrane prepared with PVA-g-POEM exhibited a high CO₂ permeance (347.3 GPU) and moderate selectivity (21.6 for CO₂/N₂). This performance is superior to other PVA-based membranes reported to date and is close to the target area for commercialization. The improved separation performance is due to the intermingled CO₂-philic POEM side chains and the decrease in crystallinity of PVA.

聚合气体分离膜由于其环保的合成工艺和低成本而成为减轻与全球变暖直接相关的温室气体排放的可行解决方案。通过非石油路线合成的聚乙烯醇（PVA）是一种环保材料，具有良好的成膜性能，良好的相容性和水溶性等多种优势，可用于膜应用。尽管有这些好处，但PVA的阻气性阻止了其在气体分离膜中的应用。因此，我们通过一锅自由基聚合反应合成了由PVA主链和聚甲基丙烯酸氧乙烯酯（POEM）侧链组成的接枝共聚物，并将其应用于高CO ₂渗透性薄膜复合膜。通过傅里叶变换红外和质子核磁共振波谱证实了PVA- g -POEM接枝共聚物的合成。X射线衍射和差示扫描量热分析显示，PVA-的结晶克-POEM随着POEM含量逐渐降低，与PVA-克-POEM接枝共聚物转变为非晶质为64重量％的含量POEM。用PVA- g -POEM制备的复合膜表现出高的CO ₂渗透率（347.3 GPU）和中等的选择性（CO ₂ / N ₂为21.6））。该性能优于迄今报道的其他基于PVA的膜，并且接近商业化的目标区域。分离性能的提高归因于亲CO _2的POEM侧链的混合以及PVA结晶度的降低。