High Permittivity Nanocomposites Embedded with Ag/TiO₂ Core⁻Shell Nanoparticles Modified by Phosphonic Acid.

Xizi Chen,Yifei Zhao,Zheng Jin,Ming Fu,Wenzhong Lu,Fei Liang

doi:10.3390/polym10060586

Abstract

In this paper, nanocomposites that contain core-shell Ag/TiO2 particles as the filler and polytetrafluoroethylene (PTFE) as the matrix were investigated. Two surfactants, namely octyl phosphonic acid (OPA) and pentafluorobenzyl phosphonic acid (PFBPA), were applied to modify Ag/TiO2 fillers for uniform dispersion in the matrix. Fourier transform infrared spectroscopy analysis of bonds between the TiO2 shells and the phosphonic modifiers shows Ti–O–P chemical bonding between the Ag/TiO2 fillers and the modifiers. Thermogravimetric analysis results show a superior adsorption effect of PFBPA over OPA on the Ag/TiO2 filler surface at the same weight percentage. For nanocomposites that contain modified Ag/TiO2 nanoparticles, the loss was reduced despite the high permittivity at the same loading. The permittivity of the nanocomposites by PFBPA is larger than that of OPA, because the more uniform dispersion of inorganic particles in the PTFE matrix enhances the interfacial polarization effect. The mechanism of enhanced dielectric performance was studied and discussed.

Highlights

Polymer-based composites have been intensively studied for their applications in electronic and microwave devices [1,2,3,4]
1. wetting between hydrophilic fillers groups at one end and lipophilic groups at theisother, In this paper, we develop a facile and general method for the synthesis of a PTFE-based and lipophilic polymer by producing chemical bonds [16,17,18]
The use of phosphonic acids leads to a more homogeneous particle and to improve the lipophilicity of Ag/TiO2 core–shell NPs, we investigated the dielectric property of distribution, and improves the dielectric properties of the whole composite

Summary

Introduction

Polymer-based composites have been intensively studied for their applications in electronic and microwave devices [1,2,3,4]. Polymers have a number of attractive properties, such as low processing temperature, low leakage current, and low Young’s modulus at relatively low permittivity and thermal conductivity. To meet the developing trends of miniaturization and integration of electronic systems, various different fillers have been embedded in polymers [5]. Silver nanoparticles (NPs) were chosen as the core in our study because of their excellent thermal, electric, and optical performance. Much research has focused on finding a suitable insulator/semiconductor shell for silver NPs, to reduce the loss of silver-polymer composites [9,10]

Methods

Results

Conclusion