Pyroelectric behavior and dielectric properties of linear copolysiloxane/eicosylamine superlattice |
| |
Authors: | Email author" target="_blank">A RM?YusoffEmail author WH Abd?Majid |
| |
Institution: | (1) Physics Department, University of Malaya, Material Science Laboratory, 50603 Kuala Lumpur, Malaysia |
| |
Abstract: | The pyroelectric behavior and dielectric properties of a superlattice
containing a Langmuir-Blodgett (LB) film of alternately monomeric
eicosylamine and linear copolysiloxane substituted with aromatic acid side
chains have been investigated in the temperature range of
C.
The pyroelectric coefficient of the superlattice increases with temperature,
exhibiting the highest coefficient of 6.2 ± 0.2
cm
K-1
at 29 °C. The dielectric behavior of the superlattice is investigated by
examining the dielectric loss and capacitance in the frequency range of
102 to 105 Hz. The maximum loss values for all temperatures in the
range occur at a frequency ∼5000 Hz which correspond to a relaxation
time of 3.18 × 10-5 s. The Cole-Cole plots obtained
experimentally are found to be broad and fall inside the semicircle derived
from the Debye relaxation theory. However, they agree fit with the
semi-empirical Cole-Cole relaxation model. The parameter α obtained
from the Cole-Cole relaxation model decreases with temperature indicating
the rise in the internal degrees of freedom of the dipole in the
superlattice. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|