The commercial polyetherimide sulfone polymer Extem was blended with polyethersulfone (PES) to achieve a new, highly selective membrane for CO₂/N₂ separation in order to allow for a breakthrough in carbon capture applications. The miscibility and molecular interaction between PES and Extem for blend compositions 80/20, 50/50 and 20/80 w/w were evaluated. Differential Scanning Calorimetry showed that of all the blend compositions, only the 20/80 blend is miscible as a single glass transition temperature was observed, lying between the glass transition temperatures of PES and Extem. FTIR spectra revealed shifts in functional group frequencies of the polymer blends, suggesting inter-molecular interactions between the polymer chains of Extem and PES. XRD patterns of the 20/80 blend showed a much lower characteristic peak intensity compared to other blend compositions, which indicates strong inter-molecular interactions. The density of the polymer blends was lower than that of the pure polymers, which is related to a decrease in fractional free volume. The separation performance of membranes synthesized with these blends was investigated for a gas mixture containing 15% vol. CO₂. Blend membranes were limited by the tradeoff between permeability and selectivity, except for the 20/80 blend, which interstingly had a permeability and selectivity more than threefold that of other membranes, as the values hovered around the Robeson’s upper bound. The miscibility of Extem/PES therefore resulted in a new polymer material, which is a potential candidate for carbon capture applications.

将商业化的聚醚酰亚胺砜聚合物Extem与聚醚砜（PES）共混，以获得一种新型的高选择性CO ₂ / N ₂膜分离，以便在碳捕集应用中取得突破。评价了PES和Extem之间的共混组合物80 / 20、50 / 50和20/80 w / w的混溶性和分子相互作用。差示扫描量热法显示，在所有共混物组合物中，仅20/80共混物是可混溶的，因为观察到单个玻璃化转变温度位于PES和Extem的玻璃化转变温度之间。FTIR光谱揭示了聚合物共混物官能团频率的变化，表明Extem和PES的聚合物链之间存在分子间相互作用。与其他共混物组合物相比，20/80共混物的XRD图谱显示出低得多的特征峰强度，这表明强烈的分子间相互作用。聚合物共混物的密度低于纯聚合物，这与自由体积分数的减少有关。研究了用这些共混物合成的膜对含15％（体积）的气体混合物的分离性能。一氧化碳₂。共混膜受到渗透率和选择性之间的权衡的限制，除了20/80共混物外，其渗透率和选择性是其他膜的三倍以上，因为其值徘徊在Robeson的上限附近。因此，Extem / PES的可混溶性导致了一种新的聚合物材料，这是碳捕获应用的潜在候选者。