傳統的聚醯亞胺（PI）合成需要高度依賴具危險性的雙極性非質子溶劑，這對人體健康與環境構成了顯著風險。為了應對此挑戰並擴充 PI 合成的綠色溶劑資料庫，本研究探討了一系列由乙酸與四級銨鹽（四烷基氯化銨）組成之深共晶溶劑（DESs），將其作為永續的反應溶劑，並首次成功開發以該系統合成聚醯胺酸（PAA）前驅物之製程，進而將其應用於高性能聚醯亞胺之合成。
首先，以含氟聚醯胺酸（PAA）類型之系統為例，經優化的 DES 配方展現出優異的化學選擇性與溶解度，其所製得的 PAA 前驅物在固有黏度與分子量表現上，均與傳統極性非質子溶劑二甲基乙醯胺（DMAc）合成之對照組相當。隨後，將 PAA 前驅物經由熱醯亞胺化製成 PI 薄膜，其熱機械性能與介電特性皆與 DMAc 製得者相仿，證實了該 DES 溶劑的可替代性；另外本研究也進行了DES溶劑應用於化學醯亞胺化法合成的相關實驗，結果表明，DES作為一步法合成PI之介質同樣也有巨大的潛力。
為了進一步驗證此溶劑的通用性，本研究擴大合成了一系列具不同結構特徵的含氟聚醯亞胺，有效減少了 PAA 前驅物中的水分與溶劑殘留；此項改良使得熱亞胺化後的 PI 薄膜具有更高的透明度。而在進行化學醯亞胺化的結果也顯示出DES合成出的PI具有更高的聚合度，這些研究結果都顯示，本研究所提出的 DES 平台不僅是可行的綠色替代方案，亦是生產高性能聚合物的多功能加工工具。

Traditional polyimide (PI) synthesis relies extensively on hazardous dipolar aprotic solvents, posing significant health and environmental risks. To address this challenge, this study investigates a series of deep eutectic solvents (DESs) comprising acetic acid and quaternary ammonium salts as sustainable reaction solvents for PI synthesis. Using a fluorinated poly(amic acid) (PAA) model system, an optimized DES formulation (tetraethylammonium chloride/acetic acid, TEAC-AC, molar ratio 1:3) was developed, demonstrating excellent chemoselectivity and solubility. PAA precursors were synthesized at room temperature and subsequently thermally imidized to form PI films. The PAA precursors synthesized in the DES exhibited inherent viscosities and molecular weights comparable to or higher than those of control samples prepared in the conventional solvent, dimethylacetamide (DMAc). The resulting PI films possessed thermomechanical and dielectric properties comparable to those from DMAc, confirming the substitutability of the DES solvent. Furthermore, the DES platform significantly reduced water absorption, thereby lowering the dissipation factor, and improved optical transparency. The system also presented a significant synthetic advantage in promoting chain growth during an alternative one-step chemical imidization. These findings demonstrate that the proposed DES platform serves as both a viable green alternative and a multifunctional processing tool for high-performance polymers.

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