This invention relates to a core/shell impact modifier having as a core a copolymer or terpolymer having from 25 to 75 percent by weight of 2-ethylhexyl acrylate (2-EHA) monomer units with from 25 and 75 percent by weight of n-octyl acrylate (n-OA) monomer units. This core-shell impact modifier is used in performance polymers to improve low temperature impact performance.