本研究建立一套液滴式微流體平台，用於高濃度聚醯胺酸（PAA）溶液的合成，並探討液滴穩定化策略，目標為製備高性能、低介電聚醯亞胺（PI）材料。在液滴生成方面，採用 T-junction 與共軸流道設計。共軸流道搭配 PDMS 疏水塗層可有效改善 DMAc 液滴下沉與黏壁問題，提升液滴對稱性與穩定性。
　　為防止液滴收集後融合，測試多種界面活性劑皆無法穩定 DMAc 液滴，後續引入雙重乳液與皮克林乳液策略。結果顯示，添加表面改質碳酸鈣奈米粒子的皮克林乳液能有效包覆液滴界面，抑制融合現象，並成功應用於後續 PAA 聚合反應。濃度提升實驗顯示，15 wt% 與 20 wt% PAA 溶液皆可穩定形成液滴，微流體製程具有較佳黏度穩定性與鏈段控制能力。GPC 分析指出，20 wt% 微流體樣品的多分散性指數（PDI）為 1.73，優於批次製程之 1.80，顯示微流體反應均勻性更佳。25 wt% 高濃度條件下，批次反應攪拌失效，微流體系統亦發生堵塞，改以重力滴落方式成功產生大型液滴（約 3000 μm）。
　　此外，PI 性質分析顯示微流體製程所得聚醯亞胺薄膜在熱穩定性與介電性質方面與批次製程相當，但在光學性質上展現較高透光度，顯示其具備更佳的光學性質與潛在應用價值。
　　本研究證實微流體系統於中高濃度條件下具備良好反應穩定性與聚合控制能力，皮克林乳液可有效提升液滴穩定性，而重力滴落技術則提供高黏度條件下的可行替代方案。

This study developed a microfluidic droplet platform for synthesizing high-concentration poly(amic acid) (PAA) toward low-k polyimide (PI) applications. T-junction and co-flow channels were tested for droplet generation, with the latter combined with PDMS surface modification to overcome DMAc adhesion. Surfactant-based stabilization (Tween, Span, SDS, C12TAB) proved ineffective due to poor compatibility with polar solvents. Pickering emulsions using CaCO₃ nanoparticles (2.5 wt%) in n-hexadecane successfully stabilized DMAc and PAA droplets. Polymerized PAA droplets were purified via acid wash and vacuum drying. At 15–20 wt% PAA, microfluidic synthesis showed superior viscosity stability and narrower molecular weight distribution (PDI = 1.73–1.80) compared to batch synthesis. For 25 wt% PAA, injection failed due to high viscosity, so a gravity dripping method was applied to form large (~3000 μm) but stable droplets. This work demonstrates an effective strategy for stable droplet formation and polymerization in high-viscosity systems via Pickering stabilization.

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