Synthesis And Mesomorphism Of Schiff-Base Calamitic Liquid Crystals And Triphenylene Discotic Liquid Crystals

Liquid crystals with good electro-optical properties play an important role in flat display industry, and bring the society into mobile information times. Discotic liquid crystals possess high charge carrier mobility and show huge potential application as organic electronic materials. This thesis reported the molecular designing, synthesis and mesomorphism of a series of new Schiff-base rod-like liquid crystals and two series of triphenylene discotic liquid crystals. The purity and structure characterization of these compounds were carried out with 1H NMR, IR, EA, and Mass. Thermal gravimetry analysis (TGA) showed these compounds have good thermal stability up to 300oC. The thermotropic liquid crystal properties were studied through polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The structure-property relationship of these molecules was proposed, and it is hopefully to contribute to the molecular designing and practical application of these liquid crystals as new materials.The thesis consists of four chapters:1. Chapter one briefly introduced the elementary knowledge about liquid crystal materials, and further discussed the important role played by liquid crystalline materials as environmental friendly materials.2. Chapter two reported the synthesis of Schiff-base rod-like liquid crystals with CH2O bridge, with structure of X-C6H4-N=CH-C6H3(Y)-OCH2-C6H4-COOC16H33,...