Mesophase Identification in Thermotropic Polymers

A major question in the liquid crystal field relates to the identification of the various mesophases. Several methods may be used (26). 

Optical pattern or texture observations with a polarizing microscope. Isotropic liquids have no texture, while both regular crystals and liquid crystals do. However, the texture of each type of phase is different. 

Nematic and smectic phases can be distinguished by DSC on the basis of the magnitude of the enthalpy changes accompanying the transition to the isotropic phase. 

Possibilities of inducing significant molecular orientation by either supporting surface treatments, or external electrical or magnetic fields. 

Small-angle X-ray studies can be used to establish molecular long-range 

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