臺灣博碩士論文加值系統

本研究主要在研究具有液晶相之離子性咪唑基鹽化合物衍生物，多碳鏈取代基咪唑鹽，以及寡聚乙二醇取代基咪唑鹽的液晶相變化熱行為。因為多碳鏈取代基咪唑鹽分子結構上在環上接有羥基，所以可與之前實驗室所作的系列做比較。液晶相是經由偏光顯微鏡、微差掃描卡計鑑定。其分析結果發現有第三側鏈取代的咪唑基鹽化合物比只有雙碳鏈取代咪唑基鹽化合物，在熔點上溫度較高，但是液晶相範圍卻較窄，這可能是因為有醚連結基所導致的結果，並且兩個系列的液晶範圍變化十分有趣，因為氫鍵與側鏈取代基的效應，使得雙取代衍生物 IM(OH)R2Br的液晶範圍是隨碳鏈增加而變寬，而三取代衍生物IMOR3Br則恰巧相反，兩者液晶相都是 SmA。另外依文獻報導的方式，整理出寡聚乙二醇取代基咪唑鹽化合物的合成方法，並且嘗試接上Pd金屬，但是這些產物並不具有我們所預期的液晶相。

The aim of our work is to synthesize and investigate liquid crystalline properties of N,N-dialkyl imidazolium derivatives (IM(OH)R2Br, n=10, 12, 14, 16, 18), N,N,O-trialkyl imidazolium (IMOR3Br, n=12, 14, 16, 18) and oligoethylene glycol substituted imidazolium salt. Because N,N,O-trialkyl imidazolium salts have hydroxyl group near the rigid part, we can compare these results with our previously reported simple N,N-dialkylimidazolium salts. Liquid crystalline behaviors of these compounds were investigated by differential scanning calorimetry and polarized optical microscopy. N,N,O-trialkyl imidazolium has higher melting point but smaller temperature range of liquid crystal phase. These may be due to the ether linkage near the rigid part. Both series exhibit smectic A mesophase. Attempts to synthesize oligoethylene glycol substituted imidazolium salts and the corresponding Pd-carbene complexes were unsuccessful.

一、 摘要……………………………………………………………. 1
二、 前言……………………………………………………………. 3
三、 研究動機………………………………………………………. 9
四、 實驗部份……………………………………………………….12
A. 儀器………………………………………………………12
B. 藥品………………………………………………………12
C. 實驗步驟…………………………………………………14
五、 結果與討論…………………………………………………….32
合成與特性…………………………………………………..32
液晶相的探討………………………………………………..37
六、 結論……………………………………………………………46
七、 參考文獻………………………………………………………48

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