The toughening effect of ethylene-vinyl acetate rubbers (EVM) with maleated ethylene-vinyl acetate copolymers (EVA-g-MAH) on the nylon 1010 was investigated. The addition of 5 phr (per hundred nylon 1010) EVM increased the elongation at break of nylon 1010 to a great extent. The notched Izod impact strength of nylon/EVM blends increased with increasing EVM content. Scanning electron microscope showed that the EVM particle size was around 0.5 mu m when the EVM content was 5 phr and increased with increasing EVM content. After the addition of EVA-g-MAH to nylon/EVM (100/20) blend, the average diameter of EVM particles decreased from more than 1 mu m to 0.5-0.6 mu m. EVA g-MAH could improve the adhesion between nylon 1010 and EVM. A sharp brittle-ductile transition (BDT) was observed when the interparticle distance was about 0.2 mu m, independent of the addition of EVA-g-MAH. The notched Izod impact strength of nylon/EVM blends at low temperatures was measured and the BDT shifted toward low temperatures with increasing EVM or EVA-g-MAH content. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 434-444, 2009