Blend membranes based on the poly(ethylene oxide-b-amid 6) (Pebax 1657) block copolymer and carbon dioxide (CO₂)-philic glassy polymers including polyacrylonitrile (PAN), acrylonitrile/ vinylimidazole copolymer (P(AN-co-VIm)) or corresponding amidoximated derivatives, i.e. P(AO-AN) and P(AO-AN-co-VIm), as additive were prepared using solution casting method. To increase CO₂-philic groups, acrylonitrile- based polymers were amidoximated via reacting with hydroxyl ammonium chloride (NH₂OH.HCl) reagent where amidoximation process was evaluated by FTIR and ¹H NMR. Compatibility and morphology of components in the blend membranes and blend density were examined by ATR-IR and DSC, FE-SEM and densitometry tests, respectively. Shifting of the peaks in the ATR-IR spectra showed that the Pebax 1657 chains establish a hydrogen bonding with the homo- or copolymer chains. The crystallinity and melting temperature (T_m) of polyamide (PA) domains in the Pebax 1657 decreased by increasing the amount of acrylonitrile- based polymers and their amidoximated derivatives. Also, the glass transition temperature (T_g) of the polyethylene oxide (PEO) domains increased due to the glassy nature of the additives. FE-SEM results indicated that all membranes are dense and there is a good interaction between the Pebax and the additives. The dense structure and free volume reduction in the membranes were confirmed by increasing membrane density resulting from increase in the amount of acrylonitrile- based polymer and amidoximated derivatives. The permeability of CO₂, nitrogen (N₂) and methane (CH₄) gases from pure and blend membranes was measured by constant pressure/ variable volume method at 3 bar and ambient temperature. By increasing the amount of acrylonitrile- based polymers, i.e. PAN and P(AN-co-VIm), up to 20 wt%, the permeability of CH₄, N₂ and CO₂ increased and then decreased with further increasing of the additive content. In blend membranes containing amidoximated polymers, i.e. (P(AO-AN) and P(AO-AN-co-VIm)), CO₂ permeability and of CO₂/N₂ and CO₂/CH₄ selectivity showed an increased trend up to 60%wt additive due to increased number and type of nitrogen atoms in the membrane structure. Compared to the pure Pebax 1657, CO₂ permeability and CO₂/N₂ and CO₂/CH₄ selectivity in blend membrane containing 40 wt% of P(AO-AN-co-VIm) copolymer increased by 193%, 497% and 495%, respectively.

混合膜基于聚（环氧乙烷-b-酰胺6）（Pebax 1657）嵌段共聚物和二氧化碳 (CO ₂ )-亲玻璃态聚合物，包括聚丙烯腈 (PAN)、丙烯腈/乙烯基咪唑共聚物 (P(AN-co-VIm) )) 或相应的酰胺肟化衍生物，即 P(AO-AN) 和 P(AO-AN-co-VIm)，作为添加剂使用溶液浇铸方法制备。为了增加亲CO ₂基团，丙烯腈基聚合物通过与羟基氯化铵 (NH ₂ OH.HCl) 试剂反应进行酰胺肟化，其中酰胺肟化过程通过 FTIR 和¹核磁共振。共混膜中组分的相容性和形态以及共混密度分别通过 ATR-IR 和 DSC、FE-SEM 和光密度测试进行检查。ATR-IR 光谱中峰的移动表明 Pebax 1657 链与均聚物或共聚物链建立了氢键。Pebax 1657 中聚酰胺 (PA) 域的结晶度和熔融温度 (T _m ) 通过增加丙烯腈基聚合物及其酰胺肟化衍生物的量而降低。此外，玻璃化转变温度 (T _g) 的聚环氧乙烷 (PEO) 域由于添加剂的玻璃性质而增加。FE-SEM 结果表明所有膜都很致密，Pebax 和添加剂之间有良好的相互作用。膜中的致密结构和自由体积减少通过增加基于丙烯腈的聚合物和酰胺肟化衍生物的量导致的膜密度增加来证实。来自纯膜和混合膜的 CO ₂、氮气 (N ₂ ) 和甲烷 (CH ₄ ) 气体的渗透率通过恒压/可变体积法在 3 巴和环境温度下测量。通过增加丙烯腈基聚合物，即 PAN 和 P(AN-co-VIm) 的量，高达 20 wt%，CH ₄的渗透性，N₂和CO ₂随着添加剂含量的进一步增加而先增加后减少。在含有酰胺肟化聚合物（P（AO-AN）和P（AO-AN-co-VIm））的共混膜中，CO ₂渗透率和CO ₂ /N ₂和CO ₂ /CH ₄选择性呈上升趋势由于膜结构中氮原子的数量和类型增加，添加到 60%wt 的添加剂。与纯 Pebax 1657 相比，CO ₂渗透率和 CO ₂ /N ₂和 CO ₂ /CH ₄ 含有 40 wt% P(AO-AN-co-VIm) 共聚物的共混膜的选择性分别提高了 193%、497% 和 495%。