Effects of Nanoparticle Surface Treatment on the Crystalline Morphology and Dielectric Property of Polypropylene/Calcium Carbonate Nanocomposites

It is well known that the morphology is one of the most important factors to affect the dielectric properties of polymeric nanocomposites. In this work, it is thought that the interfacial interaction between nanoparticles and polymer matrix is one of the most important factors affecting the crystalline morphology of the nanocomposites. So the effects of the surface-treatment of CaCO₃ nanoparticle on the crystalline morphology of polypropylene (PP)/CaCO₃ nanocomposites were investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), polarized optical microscope (POM) facilities. The dielectric properties of the nanocomposites were tested using the dielectric analyzer (DEA) at room temperature. The results showed that the nanoparticles treated with a compound surface-treating agent (CA-2) induced much more beta-phase crystal in the nanocomposites than that with a single surface-treating agent (CA-1). The relations between the dielectric properties and morphology of the nanocomposites were discussed

Introduction

Polymeric nanocomposites have attracted considerable interest and may have a powerful impact on development of dielectrics and electrical insulation [1]–[5]. Previous researches indicated that the well dispersion of nanofillers in polymer matrix and the favorable compatibility between the filler and matrix are the key factors to achieve advanced properties of the nanocomposites. Meanwhile, it is realized that the interfacial interaction between fillers and polymer matrix is very important to control the properties of nanocomposites, especially the dielectric properties [6]–[9].