MICROSCOPIC TRANSPORT-PROPERTIES IN LIQUID-CRYSTALLINE POLYMERIC MATRICES - DEPENDENCE ON THE THERMAL HISTORY

The dependence on the thermal history of the dynamical and structural properties of a polymer liquid crystal has been evidenced by different ial scanning calorimetry, infrared dichroism and non-linear electron s pin resonance (ESR) spectroscopy in a wide range of temperatures. The behaviour of the microscopic viscosity as a function of both the isoth ermal annealing and the temperature is studied and its salient feature s are interpreted in terms of cooperativity. The multiexponential deca y of the orientation correlation functions, relevant in the relaxation processes of linear and non-linear ESR spectroscopies, occurs in the supercooled and glassy phases, whereas the single exponential decay re covers above the isotropization temperature.