ABSTRACT

In recent years the interest in thermotropic materials has grown extraordinarily. These compounds usually exhibit a mesophase at temperatures above the region of the crystalline solid and before the formation of an isotropic melt. This liquid crystalline phase represents a state of order between long-range, three-dimensionally ordered crystals and the disordered amorphous or isotropic state. Thus, mesophases are characterized by the absence of positional long-range order in at least one dimension [1], but a long-range orientational order is preserved.