This invention provides activator precursor compositions and activator compositions. The activator precursor compositions are formed from a support material, a linking compound, and polyfunctional compounds having at least two aromatic groups in which at least two of said aromatic groups each has at least one polar moiety thereon. The activator compositions are formed from a support material, a linking compound, an aluminoxane, and a polyfunctional compound having at least two aromatic groups in which at least two of said aromatic groups each has at least one polar moiety thereon. Also provided are catalyst compositions, processes for forming catalyst compositions, and polymerization processes utilizing the catalyst compositions of this invention.