▎ 摘　　要

NOVELTY - Heat-sealing composite film, comprises modified polyethylene film, polyethylene terephthalate (PET) film, and aluminum foil pressing film composite. The modified polyethylene film is prepared by e.g. adding modified graphene, after ultrasonic treatment, filtering to remove the filtrate, drying the substrate to obtain the composite particle; (A4) dissolving the modified particles in the paraxylene, adding poly(tetramethylene ether)glycol (PTMG) 1000 and composite particles, stirring and dropping toluene-2,3-diisocyanate, after reacting, heating and continuously reacting, cooling and adding triethylamine, continuously stirring, and then mixing the reaction liquid with the deionized water uniformly, filtering to remove the filtrate, drying the substrate, then adding into the blow molding machine, blow molding to form film, preparing the modified polyethylene film. USE - Heat-sealing composite film used in packaging industry and protective film field. Can also be used for packaging of food products, medicinal products, and medical products. ADVANTAGE - The film solves the problem that the existing PE heat-sealing film is bad, barrier effect is generally, and it is not easy to be adhered. It can be repeatedly heat sealed, at the same time, the heat sealing film can effectively isolate water vapor, separating oxygen to make the film has good barrier effect, and the modified polyethylene film can be well bonded with the adhesive, under the long time use or in special environment, and there is no hot sealing composite film opening phenomenon, it improves the film's heat sealing effect. DETAILED DESCRIPTION - Heat-sealing composite film, comprises modified polyethylene film, polyethylene terephthalate (PET) film, and aluminum foil pressing film composite. The modified polyethylene film is prepared by: (A1) dissolving maleic anhydride in acetone, stirring and adding 2-amino-1,3-propylene glycol acetone solution, stirring, heating reflux processing, adding triethylamine, acetic anhydride, nickel acetate, continuously refluxing, adding the reactant into ice water, filtering to remove the filtrate, drying the filter cake, preparing intermediate 1, adding the linear low density polyethylene particles, intermediate 1, benzoyl peroxide into a double-screw extruder, extruding and granulating, preparing the modified particles; (A2) dispersing the oxidized graphene in the deionized water, adding thionyl chloride, stirring and refluxing, vacuum distilling to remove thionyl chloride and deionized water, dispersing the substrate again in the deionized water, adding diethanolamine and triethylamine, stirring, and then centrifuging to remove the supernatant, drying the substrate, preparing modified graphene; (A3) mixing the aluminum nitrate, magnesium nitrate, methanol, ethylene glycol uniformly to obtain the dropping liquid, adding sodium dodecyl sulfate, methanol, glycol, and adding dropping liquid, maintaining the pH value of the reaction liquid, heating reflux processing, then filtering to remove the filtrate, washing the substrate to neutral and drying, then dispersing in the n-butanol, refluxing treatment, adding modified graphene, after ultrasonic treatment, filtering to remove the filtrate, drying the substrate to obtain the composite particle; (A4) dissolving the modified particles in the paraxylene, adding poly(tetramethylene ether)glycol (PTMG) 1000 and composite particles, stirring and dropping toluene-2,3-diisocyanate, after reacting, heating and continuously reacting, cooling and adding triethylamine, continuously stirring, and then mixing the reaction liquid with the deionized water uniformly, filtering to remove the filtrate, drying the substrate, then adding into the blow molding machine, blow molding to form film, preparing the modified polyethylene film. An INDEPENDENT CLAIM is also included for the preparation method of repeatedly heat-sealing composite film comprising: (S1) providing PET film and aluminum foil, at 250-300℃, pressure 10-12 MPa, carrying out hot pressing treatment for 10-15 minutes to obtain the modified film; (S2) coating modified film PET surface and modified polyethylene film under the coating speed of 20-33 m/minute, coating adhesive, the modified film and modified polyethylene film in coating surface box, at 75-85°C, pressure 0.5-0.8 MPa and hot pressing film to obtain the composite film.