Abstract: This
investigation focuses on the effect of ferroelectric barium titantate (BT) on
the optical and dielectric properties of polystyrene (PS) host at different BT
concentration by weight. The absorption coefficient (a) is measured in the wavelength range from 270nm
to 800nm at room temperature for all
BT-PS composite films. The variation of the absorption coefficient (a),
absorption enhancement ratio (AER) and optical gap are reported. AER results revel that
BT ceramic highly enhances the UV absorption of PS host at UV region especially
at 300nm. Dielectric parameters
(dielectric constant dielectric loss and AC conductivity are determined at frequency range
from 100Hz to 100kHz
and temperature range from room temperature up to 140°C.
It is found that addition of BT ceramic to PS host will increase dielectric
constant, dielectric loss and AC conductivity of PS host. Besides, dielectric
loss shows a relaxation peak at 2.61kHz
for all BT-PS composites. It is shown that this relaxation is due to the
segmental motion of polymer chain with single value of relaxation time.
Increasing the temperature above will increase the dielectric
parameters (dielectric constant, dielectric loss and AC conductivity) of PS
host. Also, it is noticed that above the phase transition temperature of BT ceramic, all dielectric
parameters of BT-PS composites are highly increased.
