COEXTRUDED FILM COMPRISING TWO OUTER POLYAMIDE OR POLYAMIDE/POLYOLEFIN ALLOY LAYERS AND A CENTRAL POLYOLEFIN OR POLYAMIDE OR POLYAMIDE/POLYOLEFIN ALLOY LAYER

摘要

The invention relates to a film comprising: (i) at least one central polyolefin or polyamide or polyamide/polyolefin alloy layer and (ii) at least two outer polyamide or polyamide/polyolefin alloy layers having a surface tension of less than 34 mJ/m<2> for one of the faces, advantageously between 10 and 31 mJ/m<2>, and a surface tension of greater than 36 mJ/m<2> for the other face, advantageously from 40 to 65 mJ/m<2>. The invention also relates to covers consisting of the above film, the low surface tension face being disposed on the inside. The invention also relates to SMC sandwich structures consisting of a crosslinkable unsaturated polyester disposed between two films as above, the low surface tension face of these films being disposed on the polyester side. The present invention also relates to the use of the above films for refinishing the protective system of autoclaves. The present invention also relates to the use of the above films for extruding PMMA sheets.