A composition includes a polymer matrix, a multiple-acid-derived metal soap, wherein the metal has an oxidation state of +3 or +4. An associated method for making a rubber composition includes the steps of: combining a solvent and a multiple carboxylic, phosphonic, phosphoric, sulfuric, or sulfonic acid, or mixtures thereof, and mixing to form solution A; adding a source of metal ions to solution A and mixing to form a product A, the metal being selected from the metals having an oxidation state of +3 or +4, whereby product A includes a multiple-acid-derived metal soap; and combining the multiple-acid-derived metal soap with a diene rubber. A method of making a tire component includes the steps of: combining a solvent and a multiple carboxylic, phosphonic, phosphoric, sulfuric, or sulfonic acid, or mixtures thereof, and mixing to form solution A; adding a source of metal ions to solution A and mixing to form a product A, the metal being selected from the metals having an oxidation state of +3 or +4, whereby product A includes a multiple-acid-derived metal soap; combining the multiple-acid-derived metal soap with a diene rubber; and molding and vulcanizing the rubber composition into a tire component.