Abstract:
Polymer–ceramic composites have been prepared by dispersing Ca4La6(SiO4)4(PO4)2O2
(CLSP) ceramic filler in high density polyethylene (HDPE) matrix through melt mixing.
Scanning electron micrographs reveal the extent of filler dispersion. The dielectric properties
at 1 MHz and 5 GHz have been investigated as a function of filler content. The relative
permittivity increases with filler loading, maintaining a low dielectric loss. The
composite with highest filler loading of 0.4 volume fraction shows a relative permittivity
of 5.1 and dielectric loss of 2.3 10 3 at 5 GHz. Experimentally observed values of relative
permittivity at 5 GHz have been compared with the values calculated using various
theoretical models. Both the coefficient of linear thermal expansion and tensile strength
have been observed to decrease with filler loading reaching a minimum value of
117 ppm/ C and 20.7 MPa, respectively, at 0.4 volume fraction of filler. The composite
with maximum filler loading of 0.4 volume fraction shows the highest thermal conductivity
(TC) and is 1.2W m1 K1.
