Creation of Molecular Glasses and Elucidation of the Relationship between Structures, and Properties and Functions

为了制造分子玻璃，设计和合成了新型的pi-电子星爆分子和其他pi-电子体系。在相对较高的玻璃化转变温度下，它们很容易形成稳定的非晶玻璃。研究了分子结构与玻璃化性能、稳定性和玻璃化转变温度的关系。对几种形成非晶玻璃的化合物的x射线晶体结构分析，提供了分子结构与玻璃形成性能之间关系的信息。研究了分子玻璃中的电荷输运。测定了几种分子玻璃的空穴迁移率，分析了分子玻璃中空穴迁移率与温度和电场的关系。结果，获得了分子结构与电荷输运性质之间关系的重要信息。此外，首次在分子玻璃中观察到空穴漂移迁移率与负电场的依赖关系。研究了偶氮苯衍生物分散在分子玻璃中的光致变色性，并与分散在聚苯乙烯中的光致变色性进行了比较。测定了分子玻璃中正电子的湮灭寿命。结果表明，分子玻璃的局部自由体积小于聚合物玻璃。利用分子玻璃制备了有机电致发光器件，并对其性能进行了研究。研究了空穴层和电子输运层界面上杂化的形成。结果表明，利用异形发射可以改变器件的发射颜色。

For the purpose of creating molecular glasses, novel pi-electron starburst molecules and other pi-electron systems were designed and synthesized. They were found to readily form stable amorphous glasses with relatively high glass-transition temperatures. The relationship between molecular structures and glass-forming properties, and the stability and glass-transition temperature was investigated. X-Ray crystal structure analyzes of several compounds which form amorphous glasses provided information on the relationship between molecular structure and glass-forming property.Charge transport in the molecular glass was investigated. Hole drift mobilities of several molecular glasses were determined and temperature and electric-field dependences of the hole drift mobility in the molecular glass were analyzed. As a result, valuable information on the relationship between molecular structure and charge transport properties was obtained. In addition, negative-electric field dependence of hole drift mobility was observed for the first time for the molecular glass.Photochromism of an azobenzene derivative dispersed in a molecular glass was investigated in comparison with that dispersed in polystirene. In addition, positron annihilation lifetime in the molecular glass was determined. The results suggested that the local free volume in the molecular glass is smaller than that in polymer glasses.Organic electroluminescent devices using molecular glasses were fabricated and their performances were investigated. Exciplex formation at the interface between hole- and electron-transport layrs was studied. It was shown that the emission color the device can be turned by using the exciplex emission.