Summary: | 碩士 === 淡江大學 === 化學學系碩士班 === 101 === The first part of series one is make use of hexakis(phenylethynyl)benzene derivatives as the central core, and introduced o-fluorophenyl, m-fluorophenyl, p-fluorophenyl as one of side arm, respectively. Expectations by introducing fluorine atoms in different positions can make molecules arrange due to steric effect and differ in dipole orientation to become different types of arrangement. The results of the introduction of a single fluorine atom different locations in hexakis(phenylethynyl)benzene derivatives, neither liquid crystal. The second part replaced the para position of monofluorine atom to chlorine and bromine. Because introducing different halogen atoms, can affect the molecular dipole moment. The properties of the liquid crystal can be adjusted and changed with different moment. And the successful introduction of only one halogen atom, alter nematic liquid crystal molecules to a high order of the columnar liquid crystal molecules.
In series two, a compound which introducd fluorine atom onto 1, 3, 5 position and the benzene jointed terminal pentane onto 2, 4, 6 position of hexabenzocoronene central core as the target product. It’s anticipated that the repulsion of fluorine atoms between molecules twisted the whole molecules. Therefore, the distances between disc-disc arranged closer and increased the contact area of the central core, for the purpose of raising current density in the columns of the photovoltaic devices. In addition, C3 symmetry enhanced solubility and reduced its clearing point. However, only the precursor, hexaphenylbenzene derivatives, was successfully synthesized.
|