In this work, poly(lactic acid) (PLA) and nano-silver-coated
porous
clay heterostructure (PCH) hybrid films were successfully fabricated
by a twin-screw extruder. Because of the low dielectric constant of
PLA, nano-silver and PCH were employed to enhance the dielectric properties
of PLA, and nano-silver-coated porous clay heterostructures (Ag/PCH)
with different concentrations of Ag were synthesized by the green
process using ascorbic acid as a reducing agent. The results revealed
that 1 wt % of Ag-coated PCH (Ag/PCH1) exhibited the highest dielectric
constant of up to 40. The physical, chemical, thermal, mechanical,
and dielectric properties of pristine PLA and hybrid films were studied.
The results indicated that adding Ag/PCH fillers could enhance the
dielectric properties of hybrid films, increasing the dielectric constant
almost 10 times higher than that of PLA. In addition, Ag/PCH could
reinforce the mechanical properties of PLA. Furthermore, we prepared
biaxially oriented poly(lactic acid) (BOPLA) films with 4 μm
of thickness. The dissipation factor of BOPLA-Ag/PCH was improved,
while the dielectric constant was only slightly decreased. However,
the BOPLA-Ag/PCH showed better dielectric properties than those of
traditional BOPP films. As a result, PLA-Ag/PCH and BOPLA-Ag/PCH hybrid
films derived from poly(lactic acid) as biodegradable polymers with
superior properties can be applied as dielectric films in capacitors.