In this study, the effect of ionic liquid cation on the long-term stability of membranes was investigated using 1-methyl-3-octylimidazolium tetrafluoroborate (MOIM⁺BF₄^-). The initial permeance of the poly(ethylene oxide) (PEO)/AgBF₄/MOIM⁺BF₄^-membrane was 17 gas permeation unit (GPU), but after 100 hours of gas permeation experiment, it showed a low permeance of 5.3 GPU. Uv-vis spectra also showed that MOIM⁺BF₄^- could not prevent aggregation of silver nanoparticles. This indicated that the MOIM⁺BF₄^- in the membrane could not stabilize the silver nanoparticles and thus the silver nanoparticles were aggregated and acted as a gas permeation barrier. MOIM⁺BF₄^- could not stabilize the surface of silver nanoparticles because of the long chain length of the cation. This indicated that the cation of the ionic liquid, especially carbon length, was main factor affecting the stability of separation performance with time for polymer/silver salt/ionic liquid complex membranes.

中文翻译：

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离子液体对聚（环氧乙烷）/ Ag离子/ Ag纳米颗粒复合材料烯烃分离中长期稳定性的影响

在这项研究中，离子液体的阳离子的上膜的长期稳定性的影响用1-甲基-3-辛基咪唑鎓四氟硼酸盐（MOIM进行了调查⁺ BF ₄ ^- ）。的聚（环氧乙烷）的初始磁导（PEO）/的AgBF ₄ / MOIM ⁺ BF ₄ ^-膜为17的气体渗透单元（GPU），但100小时气体渗透实验后，显示出5.3 GPU的低渗透性。紫外光谱也显示，MOIM ⁺ BF ₄ ^-不能阻止银纳米粒子的聚集。这表明MOIM ⁺ BF ₄ ^-膜中的纳米粒子不能稳定银纳米粒子，因此银纳米粒子聚集并充当气体渗透屏障。MOIM ⁺ BF ₄ ^-不能稳定，因为阳离子的长链长的银纳米颗粒的表面上。这表明离子液体的阳离子，特别是碳的长度，是影响聚合物/银盐/离子液体复合膜随时间的分离性能稳定性的主要因素。