Title :
Dielectric relaxation studies in liquid crystal polymers by thermally stimulated depolarization current method
Author :
Neagu, Eugen ; Neagu, Rodica ; Daly, William H. ; Negulescu, Ion
Author_Institution :
Polytech. Inst. of Jassy, Romania
Abstract :
The thermally stimulated depolarization current method and the thermally stimulated polarization current method have been used for the study of the star poly (γ-stearyl-α, L-glutamate) polymer. The β peak appears around -88°C and is determined by side-dipole moments. Three other peaks appear: α1, α1´, and α2. The activation energy was determined for β and α2 peaks for different heating rates. A good correlation between heating rate and T m2 was found. The position of the α2 peak is very close to that determined by DSC thermograms. The α1 and α1´ peaks are strongly influenced by the thermal treatment
Keywords :
dielectric properties of liquids and solutions; dielectric relaxation; liquid crystal polymers; thermally stimulated currents; -88 degC; DSC thermograms; activation energy; alpha 1´ peaks; alpha 2 peak; alpha1 peak; beta peak; dielectric relaxation; heating rates; liquid crystal polymers; side-dipole moments; star poly ( gamma -stearyl- alpha , L-glutamate) polymer; thermal treatment; thermally stimulated depolarization current method; thermally stimulated polarization current; Crystallization; Dielectric liquids; Electrets; Heating; Liquid crystal displays; Liquid crystal polymers; Polarization; Solvents; Spine; Temperature;
Conference_Titel :
Electrets, 1991. (ISE 7) Proceedings., 7th International Symposium on (Cat. No.91CH3029-6)
Conference_Location :
Berlin
Print_ISBN :
0-7803-0112-9
DOI :
10.1109/ISE.1991.167290
