Phase separated blends of polyaryl ether ketones, polyaryl ketones, polyether ketones, polyether ether ketones and mixtures thereof with at least one polysulfone etherimide, wherein the polysulfone etherimide has greater than or equal to 50 mole % of the polymer linkages contain at least one aryl sulfone group are described. Such blends have improved load bearing capability at high temperature. In another aspect a high crystallization temperature, especially at fast cooling rates, is achieved.