Disclosed herein is a silicone-acrylate impact modifier composition, where the impact modifier composition comprises structural units derived from: at least one silicone rubber monomer, a branched acrylate rubber monomer having the formula: ##STR00001## wherein R.sup.1 is selected from hydrogen and C.sub.1-C.sub.8 linear and branched hydrocarbyl groups, R.sup.2 comprises a branched C.sub.3-C.sub.16 hydrocarbyl group; and "z" is greater than or equal to 3; a first graft link monomer; a polymerizable alkenyl-comprising organic material; and a second graft link monomer The silicone-acrylate impact modifier compositions disclosed herein are useful for making molding compositions, which are useful for producing various articles, especially for outdoor applications.