Several attempts have been made to compatibilize immiscible blends by introducing suitably- chosen polymer additives. This work studies the EPDM elastomer, chemically modified with maleic anhydride (MA), through reaction in solution of EPDM and MA, using dibenzoyl peroxide as an initiator. The best conditions for obtaining the maximum grafting were studied at different times and percentage weights of maleic anhydride. The evaluation of MA grafting onto EPDM was determined with multiple internal reflectance infrared spectroscopy as discussed in detail.