Abstract:
The aim of this project is the development of a method for the production of
conductivity graded polymeric materials through the in-situ reduction of
Graphene Oxide (GO). These types of composites can be used for the
reduction of electrical field concentrations observed in several applications,
such as cables, cable joints, microelectronic components and bushings. The
evolution of electrical conductivity of GO was monitored during thermal
reduction under isothermal and dynamic heating thermal conditions and
compared with the kinetics of the reduction reaction as observed using
calorimetry. These results were replicated in epoxy/GO composite to prove the
feasibility of in-situ reduction and capabilities for controlling this process. In
addition, reduction was achieved in epoxy/GO composites using infrared
continuous and pulsed laser. It was shown that thermal reduction is possible in
the cured epoxy composite at relatively low temperatures up to 26ᴼC. The
kinetics of reduction follows a double mechanism which can be represented
using a double n-th order process. Electrical measurements showed that
conductivity increased significantly up to 0.12 S/m for dry particles and 0.09 S/m
for the composite. Heat transfer by conduction and irradiation on specific areas
resulted in selective reduction, and a conductive graded material.