Title :
High frequency dielectric investigation of ferroelectric and melting transitions of vinylidene fluoride copolymers
Author :
Johnson, G.E. ; Anderson, E.W. ; Furukawa, T. ; Tajitsu, Y.
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
Abstract :
The ferroelectric, paraelectric, and melt regime relaxation behaviors of copolymers of vinylidene fluoride with both trifluoroethylene and tetrafluoroethylene have been studied in the 1 to 1000 MHz range from 25 to 160 °C. The data were fitted to obtain both the transition strength and characteristic relaxation time as a function of temperature. The observed temperature-dependent properties are consistent with a cooperative two-site model. The remnant polarization of the ferroelectric is lost in the paraelectric regime and then cooperatively is lost in the melt with the loss of crystalline order
Keywords :
dielectric relaxation; ferroelectric transitions; melting; polymer blends; 1 to 1000 MHz; 25 to 160 degC; characteristic relaxation time; cooperative two-site model; ferroelectric transitions; melting transitions; paraelectric regime; relaxation behaviors; remnant polarization; temperature-dependent properties; tetrafluoroethylene; transition strength; trifluoroethylene; vinylidene fluoride copolymers; Automatic control; Crystallization; Dielectrics; Ferroelectric materials; Frequency; Impedance; Influenza; Liquid crystal displays; Liquid crystal polymers; Switches;
Conference_Titel :
Properties and Applications of Dielectric Materials, 1991., Proceedings of the 3rd International Conference on
Conference_Location :
Tokyo
Print_ISBN :
0-87942-568-7
DOI :
10.1109/ICPADM.1991.172183
