The present invention relates to a composition comprising at least two grafted copolymers having a polyolefin basic polymer chain and polyamide grafts, the polyamide grafts being 5 wt % and 35 wt % of the composition bonded to the first and second copolymer as well as a third component selected among certain polyamides, polyethylenes or polypropylenes or a mixture thereof. The invention also relates to a multilayer structure comprising a plurality of adjacent layers, at least one of which consists of the aforementioned composition.