Investigation on breakdown properties of low-density polyethylene / nano-ZnO composites

The dielectric properties of Nano-composites has attract tremendous attention during the past decade. In present paper, the silane coupling agent (KH-570) and titanate coupling agent (105, 101, TC-F) is used as modifiers. The nanometer zinc oxide which has been modified by KH-570 or TC-F etc is added to the low density polyethylene. In the end, the electrical breakdown properties of the composites are investigated. The test results show that when the content of nano-ZnO was 3%, breakdown field strength of the composites is higher than origin LDPE 11%. The smaller ZnO particles in size, the higher breakdown strength of the nano-composite with the same content of nano-ZnO is. The breakdown strength of nano-composites with nano-ZnO which is treated by silane coupling agent (KH-570) is higher than those with nano-ZnO treated by titanate coupling agent. It can be found that combination of nanometer zinc oxide and polyethylene macromolecular chain is effectively improved by infrared spectrum.

I. Introduction

Polyethylene is a thermoplastic resin which has the good comprehensive performance [1], but LDPE itself has some defects and insufficiency. Under high voltage for a long time, the insulation performance of PE will decline. In order to improve LDPE insulation performance, many scholars begin to pay attention to nano additives which can influence electrical properties of LDPE. As nanoparticles have many unique properties than the conventional materials, the polymer/nanocomposite has become an important research focus of attention [2]–[4]. The related studies in the field of dielectric show that the interface structure of the large grain size is different from that of nanometer grain, the experiment results have confirmed that [5] different structures can also cause the difference of performance [6].