Glass transition and crystallization of ODIC phase in nematic liquid crystal

Abstract

Molecular dynamics of 4-(2,3-difluoro)-pentylphenyl-trans-4-(2,3-difluoro)- pentylcyclohexyl benzoate liquid crystalline material was investigated by using broadband dielectric spectroscopy (BDS) at temperature range 173 – 410 K and frequency range 10-1-107 Hz. In the same temperature region, calorimetric measurements using by differential scanning calorimetry (DSC) and polarized optical microscopy (POM) observations were carried out. The investigated substance shows isotropic and nematic liquid phases. Melt and cold crystallization of two disordered crystals (ODIC) were observed. Additionally, glass transition of ODIC crystalline phase was found. Solidification processes were described at various cooling and heating rates in both thermodynamic and dynamic ways.