This invention relates to a carbon black modified by a two step process in which carbon black is initially treated with functional monomers by an electropolymerization process to form a functionalized carbon black having an initial polymer attached to, of grafted to, the carbon black following which (A) at least one diene monomer, or (B) living anionic catalysis prepared polymer, is introduced to the functionalized carbon black to continue the polymerization, starting from a living end of the initially formed polymer, and thereby form an extended diene-based polymer. By the addition of the diene monomer or the live anionic polymer to form the associated extended diene-based polymer, it is contemplated that the modified carbon black is rendered more compatible with diene-based elastomers. Such modified carbon black may be used, for example, as reinforcement for component(s) of various articles of manufacture, including tires. Accordingly, an article of manufacture is provided, such as for example a tire, having at least one component of a rubber composition which contains such modified carbon black.