Multilayer structure comprising at least one couple (L1-L2) of adjacent layers (L1) and (L2), wherein: the layer (L1) comprises at least one polymer composition (C1) comprising: (i) at least one semi-aromatic polyamide, and (ii) at least one impact modifier (I1); the layer (L2) comprises at least one polymer composition (C2) comprising: (i) at least one un-functionalized polyolefin (PO2); (ii) at least one functionalized polyolefin (FPO2), the functionalized polyolefin comprising functional groups chosen from carboxylic groups, their esters, their anhydrides and their salts. Process for manufacturing such multilayer structure, which comprises co-extruding or co-blowmolding polymer compositions (C1) and (C2) so as to obtain one couple (L1-L2) of adjacent layers (L1) and (L2).Shaped article comprising such multilayer structure and process for manufacturing the shaped article.