Filler-elastomer interactions: Effect of ozone treatment on adhesion characteristics of carbon black/rubber composites

In this work, the changes in surface and adhesion characteristics of carbon black/rubber compoundings treated by ozone technique are investigated in different treatment times. The surface properties of carbon blacks are studied by contact angle measurement and their adhesion characteristics are determined by crosslinking density and tearing energy (G_IIIC) of the composites. As a result, it is found that the increasing of the ozone treatment time leads to an increase of the introduction of oxygen-containing functional groups onto carbon black surfaces and to an increase of the polar component (γS^SP) of surface free energy (γs), resulting in improving the crosslink density and tearing energy (G_IIIC) of the composites. The results can be explained by the fact that the polar functional groups of carbon black surfaces by the treatment lead to an increase of the adhesion at interfaces between carbon blacks and polar rubber matrix.