KINETICS OF 3-DIMENSIONAL ORDERING IN THE THERMOTROPIC LIQUID-CRYSTAL POLY(DECAMETHYLENE-4,4'-DIPHENOXY TEREPHTHALATE)

Differential scanning calorimetry has been used to study the isothermal kinetics of three-dimensional ordering from the liquid crystalline and isotropic states in poly(decamethylene-4,4'-diphenoxy terephthalate). Different transformation rates were obtained for different conditioning temperatures from both the mesophase and the isotropic state, indicating that the mesophase has a strong influence on the kinetics. The isotherms obtained follow the Avrami relation with an exponent of n = 2 for the kinetic studies from the isotropic melt, and exponents n = 2 and 3 for the studies from the mesophase. A nucleation and growth process was assumed in the determination of the temperature coefficient of the transformation. A break in this coefficient for the transformation from the mesophase has been identified for the first time and has been related to changes in the Avrami exponent.