Core-shell structured CaCO3@CNF for enhanced dielectric properties of polymer nanocomposites

• Published in: Applied surface science 2019-09, Vol.487, p.77-81
• Main Authors: Zhang, Quan-Ping, Zhu, Wen-Fan, Liang, Dong-Ming, Wu, Xiao-Li, Chen, Rui-Chao, Sun, Nan, Li, Yin-Tao, Zhou, Yuan-Lin
• Format: Article
• Language: English
• Subjects: Conductive fillers; Core-shell structure; Dielectric constant
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.05.060

Polymer composites filled with conductive particles for high dielectric constant (high-κ) have been extensively studied due to their distinct advantages such as good processability, flexibility and lightweight. However, to achieve high dielectric constant usually requires high loadings of filler, which may bring conductivity leading to large dielectric loss. Here, insulative CaCO3 is uniformly coated on the surfaces of carbon nanofibers (CNFs) via a facile self-assembly route, resulting in a core-shell structured CaCO3@CNF. Blending it with epoxy resin shows an obvious enhancement in dielectric constant to neat epoxy resin due to the presence of 2.1 wt% CNFs in composite. Importantly, uniform dispersion of the core-shell structure with about 80 nm insulating shell can effectively block electron current. Then reduced dielectric loss and enhanced dielectric constant could occur simultaneously, which is significantly positive to the composites for further electric energy storage. [Display omitted] •A facile self-assembly of a core-shell structure is provided.•Conductive CNFs is uniformly covered with insulating CaCO3 shell.•The CaCO3@CNF is greatly potential use for polymer dielectrics.