分子動力模擬被用來dimethylformamide(DMF)/water混和溶液在poly(vinyl alcohol)(PVA)/poly(acrylic acid)(PAA)交聯薄膜中滲透汽化分離的研究。利用多種模擬技巧建構出50%PVA+50%PAA交聯薄膜。模擬指出純水溶液系統中，水分子很容易滲透過薄膜。在DMF/water混和溶液系統時，水分子滲透過薄膜的數量隨著DMF濃度上升而減少。這是因為DMF佔據薄膜孔洞，阻擋水分子的滲透。水分子滲透過PVA/PAA薄膜的能障約為20至25Kcal/mol。薄膜中水分子的擴散係數大於水在溶液中，這是因為水在薄膜孔洞中具有較高的機動性。DMF/water混和溶液在PVA/PAA交聯薄膜中的分離效率會隨著DMF濃度的變化而改變。

Molecular dynamics simulations were carried out to investigate the pervaporation of dimethylformamide(DMF)/water mixtures through poly(vinyl alcohol)(PVA)/poly (acrylic acid)(PAA) blend membranes. The blend membranes were constructed by various simulation techniques, which were composed 50% PAA and 50% PVA. The simulation showed that water molecules were easy to penetrate through the membrane in pure water system. In DMF/water mixture, the number of water molecules which penetrated through the membrane was significantly reduced with the increase of DMF content. Because DMF occupied the polymer pores, hence, blocked the water penetration. The energy barrier of the water molecules which penetrated through the PVA/PAA membranes was about 20 to 25 Kcal/mol. The diffusion coefficient of water in polymer membrane was found larger than that in water liquid because of the relatively high mobility of water in polymer pores. The separation efficiency of DMF/water mixture by PVA/PAA blend membrane is varied with the content of DMF.

論文審定書.....................................................................................................................i
謝誌................................................................................................................................ii
中文摘要...................................................................................................................... iii
Abstract .........................................................................................................................iv
目錄................................................................................................................................v
圖次..............................................................................................................................vii
表次...............................................................................................................................ix
第壹章 緒論................................................................................................................1
第貳章 原理及方法....................................................................................................3
2-1 簡介................................................................................................................3
2-2 分子動力模擬................................................................................................4
2-3 Verlet Leapfrog演算法.................................................................................5
2-4 分子動力模擬計算流程................................................................................6
2-5 力場................................................................................................................7
第參章 建模與參數設定............................................................................................9
3-1 建構PVA-PAA聚合薄膜方法....................................................................9
3-2 建構模擬系統..............................................................................................11
3-3 模擬參數設定..............................................................................................12
第肆章 結果與討論..................................................................................................13
4-1 水分子在PVA-PAA薄膜滲透過程..........................................................13
4-2 各濃度下水分子滲透數量比較..................................................................16
4-3 純水系統下水分子滲透情形......................................................................17
4-4 不同濃度下水分子滲透情形......................................................................19
4-5 徑向分佈函數(Radial Distribution Function, RDF) ...................................22
4-6 水分子的擴散係數(Diffusion Coefficient).................................................25
4-7 水與DMF在薄膜中的軌跡圖...................................................................26
4-8 水分子滲透薄膜的能障..............................................................................29
4-9 水與DMF的分離率...................................................................................34
第伍章 結論..............................................................................................................35
第陸章 參考文獻......................................................................................................37

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