本篇文章主要是探討含 triketone 有機液晶材料設計與物性，分子設計中藉由改變側鏈基碳數及支數，進而探討其對液晶形成所產生之影響。實驗藉由1H及13C-NMR鑑定合成化合物之結構及純度，並由元素分析確定化合物之純度。液晶相物性部分之探討則藉由偏光顯微鏡下對不同相溫度變化範圍及液晶相結構種類作一初步觀察，再以熱差掃描卡計(different scanning calorimetry)及變溫粉末繞射儀(temperature-dependent X-ray diffraction)對相變化溫度及熱焓量變化作判定及液晶相結構種類作確認 。 系列一：合成出具有triketone結構的液晶分子，探討不同側鏈基碳數(n = 6、8、10、12、14、16) 對液晶相的影響，此系列皆具有SmA相；系列二：探討不同側鏈基支數(n = 8、10、12、14、16) 對液晶相的影響，此系列中(n = 12)為室溫型液晶，具有Colr相；系列三：改變分子結構中軟硬端的比例，延伸側鏈基長度並且改變碳數(n = 8、12、16) 此系列皆具有SmA及SmC相。 In this work, we report the synthesis, characterization and mesomorphic properties of new mesogenic derivatives based on (1Z,3Z,5E)-1-(4-alkoxy)phenyl)-5-(3-hydroxypropylimino) hexa-1,3-diene-1,3-diols. The compounds were obtained by condensation reactions of triketones and 1-amino-3-proponal in absolute ethanol. All compounds were characterized by 1H-NMR and 13C-NMR spectroscope. The phase behavior of these mesogenic compounds were characterized and studied by differential scanning calorimeter (DSC), polarization optical microscope (POM) and temperature dependent powder X-ray diffraction. These compounds Uts-Cn exhibited smectic A phases (SmA) and compounds Uts-3Cn exhibited rectangular columnar phase (Colr) and compounds Utso-Cn exhibited smectic A phases (SmA) and smectic C phases (SmC). All compounds Uts-Cn with one flexible terminal alkoxy chains were rod-like liquid crystals, however, compound Uts-3Cn with three alkoxy chains exhibited discotic-like liquid crystals. Each series involves a couple of compounds which have liquid crystals at room temperature.
