AbstractThe gas transport properties of polybenzoxazole (PBO)–silica hybrid membranes were investigated. The PBO–silica hybrid membranes were prepared with poly(o-hydroxy amide) (PHA) as a precursor and various alkoxysilanes via thermal oxazolization and sol–gel processes. The thermal decomposition temperature of the hybrid membranes increased with increasing silica content, indicating that the thermal stability was improved by hybridization with silica. The gas permeabilities of the PBO–silica hybrid membranes also increased with increasing silica content and thermal treatment temperature. It is worth noting that the hybrid membranes prepared with tetraethoxysilane (TEOS) as the selected alkoxysilane showed simultaneous enhancements in CO2 permeability and CO2/CH4 selectivity with increasing silica content and thermal treatment temperature. The prominent CO2/CH4 separation ability of the PBO–silica hybrid membranes prepared with TEOS might be attributable to free volume holes created around the polymer/silica interfacial area and increased intermolecular chain distance, which improved size-selective CO2/CH4 separation.The gas transport properties of polybenzoxazole (PBO)–silica hybrid membranes were investigated. The gas permeability of the PBO–silica hybrid membranes increased withincreasing silica content and thermal treatment temperature. The hybrid membranes prepared with tetraethoxysilane (TEOS) showed simultaneous enhancements in CO2 permeability and CO2/CH4 selectivity with increasing silica content and thermal treatment temperature. The prominent CO2/CH4 separation ability might be attributable to free volume holes created around the polymer/silica interfacial area and increased intermolecular chain distance.

中文翻译：

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不同烷氧基硅烷制备的聚苯并恶唑-二氧化硅杂化膜的气体传输性能

摘要 研究了聚苯并恶唑（PBO）-二氧化硅杂化膜的气体传输性能。PBO-二氧化硅杂化膜是用聚（邻羟基酰胺）（PHA）作为前体和各种烷氧基硅烷通过热恶唑化和溶胶-凝胶工艺制备的。杂化膜的热分解温度随着二氧化硅含量的增加而增加，表明通过与二氧化硅的杂化提高了热稳定性。PBO-二氧化硅混合膜的透气性也随着二氧化硅含量和热处理温度的增加而增加。值得注意的是，用四乙氧基硅烷 (TEOS) 作为选定的烷氧基硅烷制备的混合膜随着二氧化硅含量和热处理温度的增加，显示出 CO2 渗透性和 CO2/CH4 选择性同时增强。用 TEOS 制备的 PBO-二氧化硅杂化膜的显着 CO2/CH4 分离能力可能归因于在聚合物/二氧化硅界面区域周围产生的自由体积孔和增加的分子间链距离，从而改善了尺寸选择性 CO2/CH4 分离。研究了聚苯并恶唑（PBO）-二氧化硅杂化膜的传输特性。PBO-二氧化硅杂化膜的透气性随着二氧化硅含量和热处理温度的增加而增加。用四乙氧基硅烷 (TEOS) 制备的混合膜显示出随着二氧化硅含量和热处理温度的增加，CO2 渗透性和 CO2/CH4 选择性同时增强。