화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals, Vol.496, 253-268, 2008
Processes of Molecular Transformations and Self-Organization of Chromenoacridines in Liquid Crystal Matrices
The thermochromism and the crystallization of bistable chromeno[2,3-q]acridines in liquid crystals are investigated. The dependence of thermochromic properties of the dye and characteristics of the liquid crystal on the dye concentration is revealed. At small concentrations of the dye, the ordering of the LC matrix stimulates the thermotransformations of the dye and reflects in the increase of the transition temperature from the chromene form to the merocyanine form. At large concentrations of the dye the LC matrix ordering hampers the reversal transition form the merocyanine form to the chromene form, and the transition temperature reduces (Delta T = 80 degrees C). The ordering of the LC matrix impedes the crystallization of the dye and causes both a modification of the form and a decrease of the size of crystals. The influence of the dye on the LC properties is exposed in the modification of physical characteristics of the LC (reduction of the crystallization temperature) and in the oriented influence of the dye on the LC (appearance of the texture).