High performance sealable co-extruded oriented film, methods of manufacture thereof and articles comprising the same

A method of manufacturing a multilayer film comprising:

• coextruding a multilayer film comprising:
• a first layer comprising polyethylene and a second layer comprising polypropylene;
• where the second layer has a thickness of 10 to 70 μm;
• and
• a tie layer;
• where the tie layer comprises a crystalline block composite or a block composite;
• wherein the crystalline block composite comprises:
• a crystalline ethylene based polymer, a crystalline α-olefin based polymer, and a block copolymer comprising a crystalline ethylene block and a crystalline α-olefin block, wherein the crystalline ethylene block of the block copolymer is the same composition as the crystalline ethylene based polymer in the block composite and the crystalline α-olefin block of the block copolymer is the same composition as the crystalline α-olefin based polymer of the block composite, and wherein a compositional split between the amount of crystalline ethylene based polymer and crystalline α-olefin based polymer is the same as that between the corresponding blocks in the block copolymer;
• and
• wherein the block composite comprises:
• (i) a soft ethylene copolymer having polymerized units in which the comonomer content is greater than 10 mol % and having less than 90 mol % polymerized ethylene,
• (ii) a hard or crystalline α-olefin polymer, in which the α-olefin monomer is present in an amount of from greater than 90 up to 100 mol %, and
• (iii) a diblock block copolymer, having a soft segment and a hard segment, wherein the hard segment of the block copolymer is the same composition as the hard α-olefin polymer in the block composite and the soft segment of the block copolymer is essentially the same composition as the soft ethylene copolymer of the block composite, and where the tie layer is disposed between the first layer and the second layer;
• the first layer being disposed on a first surface of the tie layer;
• the second layer being disposed on a second surface of the tie layer;
• where the second surface is opposedly disposed to the first surface;
• blowing or casting the multilayered film;
• and
• biaxially orienting the film.