The effect of carbon black morphology to the thermal conductivity of natural rubber composites

Different varieties of carbon black (CB) filled rubber materials were prepared. Transmission electron microscopy was used to explore the morphology of the fillers. It shows that the connective structure of carbon black is the main factor resulting in the thermal conductivity enhancement of rubber composites with CB fillers. The enhancement is more obvious as the filling amount increases due to the increased connectivity of the CB in rubber. Furthermore, the CB aggregates with larger number of branch chains gives higher connectivity and thermal conductivity. Accordingly, the Agari model was chosen and modified to predict the thermal conductivity of the composites. Compared with all the data, the average deviation of the predicted thermal conductivities by the modified Agari model is about 4%, which is better than other classical models. (C) 2019 Elsevier Ltd. All rights reserved.