Effect of copper grafted graphite loading on cure characteristics of natural rubber composites

Abstract

Metal-coated graphite-based materials are important to effectively transmit and control heat for different electrical and electronic applications. In this study, copper grafted graphite (Cu-g-graphite) was synthesized according to a chemical process and, six natural rubber (NR) composites were prepared by varying the Cu-g-graphite loading from 2 parts per hundred parts of rubber (phr) to 10 phr at 2 phr intervals. Maximum torque and delta cure results indicated high cross-link density for the composites prepared with Cu-g-graphite. In contrast, the stock viscosity of the composites decreased with the increase of the Cu-g-graphite loading. Further, the composite prepared with 10 phr loading of Cu-g-graphite showed the highest scorch time indicating the highest processing safety. However, cure time slightly increased with the increase of Cu-g-graphite loading and, slower cure rate was indicated at higher Cu–g-graphite loading. Overall, the composite prepared with 10 phr loading of Cu-g-graphite which exhibited higher scorch safety and crosslink density compared to the others would be suitable for particular dry rubber-based applications.