A new dispersion method for the preparation of polymer/organoclay nanocomposite in the electric fields

A new electric application method was developed to prepare epoxy/organoclay nanocomposite for the electrical insulation in the ac electric fields and it could be also used in the field of various viscous polymer/organoclay systems. The applied ac electric field condition was as follows; (1) inter-electrode distance: 40 mm, (2) application voltage: 3-11 kV, (3) frequency: 60-1,000 Hz, and (4) application time: 0-60 min. To characterize the epoxy/clay nanocomposite, WAXS and TEM analyses were performed. In order to explain how the organic modifier affects the exfoliation phenomena, a mechanism of the oscillating collision of the quaternary ammonium head was proposed and the effects of the ac voltage and frequency and the organoclay content were studied.

I. Introduction

Many kinds of aluminosilicate minerals such as zeolite, bentonite, kaoline, mica, etc have been used as inorganic fillers for conventional polymer composites, in which they not only reduce the cost but also give some special properties such as electrical insulation, modulus, hardness, thermal stability, thickening, etc. [1]–[4]. However, the wide difference of the elastic modulus or the thermal expansion coefficients between the inorganic fillers and the polymer matrices weaken the interfacial characteristics inducing the decrement of mechanical, electrical, and thermal properties. Therefore, many researchers have investigated to modify the interfacial strength by reducing the internal stress on the interface through the surface treatment of aluminosilicate minerals with coupling agents or by minimizing the filler size as possible as its size can be expressed in nano unit [5]–[7].