Kang Sang Wook
Department of Chemistry, Sangmyung University, Seoul 03016, Korea.
Department of Chemistry and Energy Engineering, Sangmyung University, Seoul 03016, Korea.
Polymers (Basel). 2020 Oct 10;12(10):2316. doi: 10.3390/polym12102316.
We showed the potential of poly(ethylene--propylene) (EPR)/silver metal/-benzoquinone composite membranes for propylene/propane mixtures, i.e., a selectivity of 10 and a mixed gas permeance of 0.5 GPU (1 GPU = 1 × 10 cm (STP)/(cm s cmHg) in a previous study. In this study, we additionally found that the incorporation of fumed silica nanoparticles into EPR/silver metal/-benzoquinone (-BQ) composite membranes exhibited much higher permeance and selectivity for propylene/propane mixtures. The positive polarity of silver metal continuously increased with the increasing silica content up to the 0.1 weight ratio, as revealed by x-ray photoelectron spectroscopy (XPS). This increase in the polarity of silver metal was attributed to the enhanced interaction of -BQ with the surface of Ag nanoparticles by the increased dispersion of -BQ by fumed silica nanoparticles. Differential scanning calorimetry (DSC) also presented that the glass transition temperature (T) of the membranes was almost invariant. Therefore, the improvement of the permeance and selectivity with the silica nanoparticles was attributable to the increased polarity of the silver metal rather than the structural change.
在之前的一项研究中，我们展示了聚（乙烯 - 丙烯）（EPR）/银金属/对苯醌复合膜对丙烯/丙烷混合物的分离潜力，即选择性为10，混合气体渗透率为0.5 GPU（1 GPU = 1×10⁻¹⁰ cm³(STP)/(cm²·s·cmHg)）。在本研究中，我们还发现，将气相二氧化硅纳米颗粒掺入EPR/银金属/对苯醌（-BQ）复合膜中，对丙烯/丙烷混合物表现出更高的渗透率和选择性。如X射线光电子能谱（XPS）所示，直至重量比达到0.1，随着二氧化硅含量的增加，银金属的正极性持续增强。银金属极性的这种增加归因于气相二氧化硅纳米颗粒增加了对苯醌的分散性，从而增强了对苯醌与银纳米颗粒表面的相互作用。差示扫描量热法（DSC）也表明，膜的玻璃化转变温度（Tg）几乎不变。因此，二氧化硅纳米颗粒对渗透率和选择性的改善归因于银金属极性的增加，而非结构变化。
