The phenomena of chipping and chipping wear are complex and completely different from normal road wear. The current challenge is to understand and optimize those influential parameters. From a carbon black perspective, there are generally three aspects to improving the cut and chip resistance of a rubber compound: surface area, structure and surface activity.
Surface Area: High fineness grades create a larger surface area to which rubber molecules can bond. This results in high energy dissipation, creating an obstacle for the crack tip or tear to continue to propagate.
Surface activity: This refers to the level of volatile oxygen groups on the surface of carbon black. The less surface active the carbon black is, or the more "dead" the surface is, the more freely the rubber molecules can move and slide on the carbon black surface, creating friction. This friction is also a source of energy dissipation, slowing the growth of cracks or tears.
Construction: A lower structural grade will greatly increase the inherent tear strength. Compared to surface area and surface activity, the exact mechanism behind this phenomenon is less clear. One explanation is that the lower the structural grade, there is less rubber trapped in the filler aggregates, which allows the compound to stretch longer before breaking. This is one way to optimize "resilience".