The present invention provides multiple polymeric additive systems and processes for preparing multiple polymeric additive systems which contain a liquid component and a solid component, wherein the solid component contains two or more polymeric additive particles having different compositions. The present invention also provides polymeric compositions and processes for preparing polymeric compositions that include a polymeric component and a multiple polymeric additive system which contains a liquid component and a solid component, wherein the solid component contains two or more polymeric additive particles having different compositions. The disclosed compositions and processes are useful in the preparation of polymeric materials and articles produced therefrom.