High barrier recyclable laminated film and preparation method thereof

A polyolefin composite film, comprising, from outside to inside, an outer film, a water-barrier layer, a polyvinyl alcohol coating layer, an adhesive layer, and an inner film, wherein the outer film is an outer polyethylene film, and the inner film is a modified inner polyethylene film;

• the modified inner polyethylene film comprises the following raw materials in percentage by weight:
• 10-20% of high-density polyethylene, 30-50% of medium-density polyethylene, 20-26% of linear low-density polyethylene, 10-20% of low-density polyethylene, 8-12% of a water- and oxygen-barrier masterbatch, and 1-3% of an auxiliary agent;
• and
• the water- and oxygen-barrier masterbatch comprises the following raw materials in parts by weight:
• 10-20 parts of polycarbonate, 0.1-0.3 parts of a compatibilizer, 10-20 parts of an ethylene-vinyl acetate copolymer, 1-2 parts of single-layer graphene, and 1-2 parts of polyhedral oligomeric silsesquioxane.