氫鍵彎曲狀液晶分子(含單一彎曲吡啶基受體及數種矽氧烷酸基予體)之合成與研究

Abstract

為了完整且系統性地探討氫鍵彎曲狀液晶分子末端加入矽氧烷結構對其液晶相行為的影響，本論文實驗合成出具單一彎吡啶基及四種矽氧烷酸基的受體-予體型氫鍵彎曲狀液晶分子，實驗結果藉由1H-NMR、紅外線光譜儀、質譜以及元素分析鑑定其結構與純度，並透過DSC、POM、電性量測以及GISAXS來探討其液晶行為以及結構排列。研究結果顯示除了POSS8-NBF14分子不具有液晶相之外，其他三組氫鍵彎曲狀液晶分子皆有液晶相，S1-NBF14分子為具有氫鍵及直鏈矽氧基團之彎曲狀液晶，存在一系列的具雙傾斜性質及高規則層列結構；POSS1-NBF14分子為具有氫鍵及巨大的矽氧基團之彎曲狀液晶，存在具雙傾斜性質及高規則層列結構；C4-NBF14分子為具有氫鍵及環狀矽氧基團之彎曲狀液晶，存在高規則之層列結構。

In order to study the influence of the structure of siloxane terminal group on the mesogenic behavior of hydrogen-bonded bent core liquid crystal, a series of hydrogen-bonded bent core liquid crystal containing a bent-core pyridyl acceptor and four siloxane acid donors liquid crystal compounds were synthesized. The chemical structures of these compounds were characterized by 1H-NMR, IR spectra, MS as well as elemental analyses, and the liquid crystalline phases and mesomorphic behavior of all the compounds were identified from the results of DSC, POM, electro-optical measurement and GISAXS. Only the compound of POSS8-NBF14 can’t exhibit any mesophases, the other all exhibit, S1-NBF14 is a hydrogen-bonded complex with a linear siloxane units exhibited a series of general tilt smectic (SmCG) phases with highly ordered layer structures. POSS1-NBF14 is a hydrogen-bonded complex with a huge siloxane units exhibited a general tilt smectic (SmCG) phases with highly ordered layer structures. C4-NBF14 is a hydrogen-bonded complex with a cyclic siloxane units exhibited a highly ordered layer structures.