The invention relates to the technical field of packaging films, and particularly discloses a heat-resistant
polyethylene composite packaging film and a preparation method thereof.The
polyethylene composite packaging film comprises an inner layer, a middle layer and an outer layer, the inner layer is prepared from, by
mass, 100 parts of linear low-density
polyethylene, 28-32 parts of
polypropylene and 8-10 parts of
hydrotalcite modified blending materials, the middle layer comprises the following raw materials in parts by weight: 100 parts of low-density polyethylene, 40-60 parts of linear low-density polyethylene, 3-5 parts of a
coupling agent and 0.5-1 part of an
antioxidant, the outer layer comprises the following raw materials in parts by weight: 100 parts of modified PA6, 20-30 parts of
metallocene polyethylene and 5-8 parts of a compatilizer, functional gradient distribution is realized by adopting layered
extrusion of three-layer co-
extrusion, and PA6 and
polypropylene have a synergistic effect, so that the
composite film has excellent
heat resistance, and the service life of the
composite film is prolonged. The
hydrotalcite and the
graphene oxide have a synergistic effect, the
layered structure effectively obstructs
oxygen and
water vapor, and the obtained polyethylene composite packaging film is good in barrier property and has excellent
mechanical property and
heat resistance.