A curable rubber composition including a rubber, a plurality of ground particles, and a reactive surfactant represented by the formula: X—Y—Z where X is a reactive group capable of forming covalent links with the rubber during compounding or vulcanization, Y is a hydrophobic linkage, and Z is a polar group capable of forming self-assemblies via intermolecular interactions, and wherein the reactive surfactant is incompatible with the rubber and a method of making the same.