Two Percolation Behaviors in Binary Heterogeneous Composites for High Permittivity and Negative Permittivity

Xinshuai Li1

Shuwei Meng2

Peitao Xie2,3,Email

Yulei Wei4

Wenfeng Xu1

Guixian Li5

Gemeng Liang6

Ai Du7,Email

Kai Sun8

Zhicheng Shi1,Email

Runhua Fan8

1School of Materials Science and Engineering, Ocean University of China, Qingdao 266100, P. R. China
2State Key Laboratory of Bio-fbers and Eco-textiles Institute of Biochemical Engineering, Institute of Biochemical Engineering, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, P. R. China 
3Foshan (Southern China) Institute for New Materials, Foshan, 528200, P. R. China
4Shandong Sinocera Functional Material Co., LTD., Dongying, 257100, P. R. China
5The 8511 research Institute of China Aerospace Science and Industry Corporation Limited (CASIC), Nanjing, 210007, P. R. China 
6School of Chemical Engineering & Advanced Materials, The University of Adelaide, Adelaide, Australia
7Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
8College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai

Abstract

Percolative composite is usually studied to achieve high permittivity when the fraction of fillers reaches the percolation threshold; besides, negative permittivity has also been a research hotspot and can be obtained above the percolation threshold. However, no studies have clarified whether the two percolation behaviors are the same one. Herein, the binary heterogeneous composites consisting of titanium nitride (TiN) particles and epoxy were prepared by compression molding, dielectric performance and percolation behavior were studied. Two percolation behaviors were demonstrated with increasing the TiN content. The first percolation behavior is to describe the high permittivity while the second one is to describe negative permittivity. It is interesting to find that the two percolation behaviors are actually associated with the competitive effect between inductance and capacitance. As a consequence, a high permittivity of 419 and a negative permittivity of -18 are obtained near the two percolation thresholds (42 % and 50 %), respectively. This work presents a clear physical description for the percolation phenomenon in the view of dielectric performance. 

Two Percolation Behaviors in Binary Heterogeneous Composites for High Permittivity and Negative Permittivity