Characterizing Mesophase Transitions of 8CB Liquid Crystal using DSC and Logger Pro

The main focus of this research is to perform a detailed analysis of 4-octyl-4-cyanobiphenyl (8CB) Liquid Crystal (LC). 8CB is a family member of the nCB liquid crystal and it is a thermotropic LC that shows a change in phase transition when it is heated or cooled. The phase transitions for 8CB occur in four phases, including a crystalline (K), Smectic A (SmA), Nematic (N), and Isotropic (I) state. As 8CB goes through these states, it shows mesophases and mesophase transitions. 8CB has a tail made of eight C-H bonds and a body made of two benzene and CN groups. Further, this paper presents findings derived from the utilization of Differential Scanning Calorimetry (DSC) and explores the thermal characteristics of 8CB when subjected to heating from 0°C to 100°C and subsequent cooling from 100°C to -40°C, using ramp rates of 5, 10, and 20 °C/min respectively. This paper also includes results that can be found in this study when thermal Speed, thermal acceleration, and thermal Jerk are calculated using Logger Pro for 8CB against the time taken for these mesophase transitions. It can be seen how the peaks of these mesophases change as a function of thermal speed, thermal acceleration, and thermal jerk. These results can be explained in terms of molecular alignment and effect of temperature on their mesophases and the flexibility of 8CB’s tail.