在科技迅速發展的工業化時代，人類活動所造成的環境危害變得日趨嚴重，因此發展解決此問題的新技術越來越受到重視。絲素蛋白為一種無毒且具生物相容性的純天然高分子，利用其製作薄膜可解決環境污染問題，並達成永續發展的目的，絲素蛋白 (Silk fibroin, SF) 薄膜因其機械性能差、易溶於水，難以應用於薄膜分離程序，本研究提出一種新的方法，利用聚乙二醇 (Polyethylene glycol, PEG) 混摻以調控絲素蛋白的結晶型態並提高薄膜的穩定性，此外由於CO2與 PEG 分子鏈中醚基之間的強相互作用力，聚乙二醇/絲素蛋白混合基質薄膜呈現很高的CO2溶解係數，使PEG2.0/SF 之薄膜有最高氣體透過係數，CO2透過係數達124.08 Barrer，O2透過係數達7.07 Barrer，N2透過係數達2.89 Barrer，且CO2/N2及O2/N2選擇係數分別為43.0及2.5。
為了解決在分離過程中氣體透過係數和選擇係數之間存在trade-off問題，並進一步提升薄膜的氣體分離效能，本研究將氧化石墨烯 (Graphene oxide, GO) 添加於聚乙二醇/絲素蛋白混合基質薄膜中，利用聚合物和奈米填充材各自的優點來調控氣體分離薄膜的氣體透過係數和選擇係數，使GO0.1/PEG2.0/SF薄膜有最佳的氣體分離性能，CO2透過係數達136.46 Barrer，O2透過係數為5.85 Barrer，N2透過係數則為2.44 Barrer，CO2/N2選擇係數顯著提升至56.0，以上表明在氣體分離過程中，使用GO奈米片摻合聚乙二醇與絲素蛋白薄膜具有發展潛力。

In the rapidly developing period of technology and industrialization, the environmental impacts caused by human activities have become increasingly severe. Therefore, the development of new technologies to solve these issues is becoming more and more important. Silk fibroin (SF) is a biocompatible natural polymer and using it to make a membrane can achieve the goal of environmental protection and sustainable development. However, silk fibroin membranes are difficult to be applied in membrane separation technology due to their poor mechanical properties and high solubility in water. In this study, polyethylene glycol (PEG) was blended into silk fibroin to improve the stability of the membrane by controlling the crystalline state of silk fibroin, which was successfully used in gas separation procedures. Due to the strong interaction between CO2 and the ether groups in PEG molecules, PEG/silk fibroin mixed matrix membranes have high CO2 solubility. The PEG2.0/SF membrane exhibited the highest gas separation performance with CO2 permeability of 124.08 Barrer, O2 permeability of 7.07 Barrer, and N2 permeability of 2.89 Barrer. The CO2/N2 and O2/N2 ideal selectivity were 43.0 and 2.5, respectively.
In order to solve the trade-off effect between permeability and selectivity, graphene oxide (GO) was added into the mixed matrix membrane to improve the permeability and selectivity of the PEG/silk fibroin membrane by taking the advantages of combining polymers and fillers. The GO0.1/PEG2.0/SF membrane exhibited improved gas separation performance with CO2 permeability of 136.46 Barrer, O2 permeability of 5.85 Barrer, N2 permeability of 2.44 Barrer, and CO2/N2 ideal selectivity was significantly enhanced to 56.0. The potential application of GO/PEG/silk fibroin membranes for gas separation process was confirmed in this study.

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