Preparation and characterization of nano‐filled polypropylene dielectric films

Abstract Modified copper calcium titanate (MCCTO) or functional activated carbon (FANC) particles were added to functional polypropylene (FPP) or heat‐treated polypropylene (HTFPP) matrix to improve the performance of FPP as dielectric films. By testing and characterizing the prepared FPP w x MCCTO y , FPP w x FANC z , FPP w x MCCTO y FANC z and HTFPP w x MCCTO y , HTFPP w x FANC y and HTFPP w x MCCTO y FANC z films, It is found that the dielectric constant and discharge energy density of each FPP w x MCCTO y , FPP w x FANC z , HTFPP w x FANC z and HTFPP w x FANC z films reach the maximum when the MCCTO and FANC loads are close to 8 and 6 wt% respectively. FPP w x MCCTO 8 FANC z and HTFPP w x MCCTO 8 FANC z series films also obtain the maximum dielectric constant and discharge energy density at FANC load approaching 6 wt%. The discharge energy density of HTFPP w 86 MCCTO 8 FANC 6 film prepared properly is 3.2 J/cm 3 , which is more than 3 times higher than that of FPP. When MCCTO and FANC loads are ≦8 and 6 wt% respectively, with the increase of additive content, More dense distribution of MCCTO and FANC was observed in FPP w x MCCTO y (or HTFPP w x MCCTO y ), FPP w x FANC z (or HTFPP w x FANC z ) and FPP w x MCCTO 8 FANC z (or HTFPP w x MCCTO 8 FANC z ) series film sections. In this paper, we propose possible explanations for the apparent improvement in dielectric constant, discharge energy density and heat resistance of capacitive films after appropriate heat treatment or addition of appropriate MCCTO and/or FANC loads.