Structure-Dielectric Property Relationship in Polypropylene/Multi-Element Oxide Nanocomposites
Aizat Azmi, Kwan Yiew Lau, Noor Azlinda Ahmad, Zulkurnain Abdul‐Malek, Chee Wei Tan, Kuan Yong Ching, A. S. Vaughan
Abstract
This paper reports on an investigation into the effects of different multi-element oxide nanofillers on the structure and dielectric properties of polypropylene (PP)-based nanocomposites. Magnesium aluminate (MgAl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ), calcium carbonate (CaCO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) and surface-modified calcium carbonate (CaCO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> T) have been added to the PP to determine their effects on thermal properties, structural changes, dielectric response and breakdown strength. The results show that PP nanocomposites containing MgAl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> possess lowered breakdown strength compared to unfilled PP. In contrast, adding CaCO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> to PP results in a higher breakdown strength of the nanocomposites compared to nanocomposites containing MgAl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> . Meanwhile, nanocomposites containing CaCO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> T possess the highest breakdown strength among the systems considered. Possible mechanisms governing these dielectric property changes under alternating current and direct current electric fields are discussed.