Abstract: By means of microscopy, scanning electron microscopy, and infraredanalysis, the course of formation of the ternary mixed blend composed ofPP-g-P(MA-co-VAc) and P(MA-co-VAc) during heterogeneous graft copoly-merization of MA/VAc mixtures onto PP, the morphological structure ofthe grafting products and the effect of the P (MA-co-VAc) content on thecrytallization behavior from melt in the presence of PP-g-P (MA-co-VAc)have been studied. The results show that the polymer blends, similar to metallic alloy,have a special composition under given conditions.