High-barrier polyester film and preparation method thereof

The invention discloses a high-barrier polyester film. The high-barrier polyester film is characterized by comprising a base film and a high-barrier resin coating applied and cured on a single surface or double surfaces of the base film, wherein the thickness of the high-barrier polyester film is 15-80 mu m; the base film is a biaxially stretched polyester film prepared from polyethylene terephthalate. The preparation method of the high-barrier resin coating comprises steps as follows: the polyethylene terephthalate chips are subjected to fusion and chip casting through an extruder and longitudinal stretching to form a thin stock chip, a single surface or double surfaces of the thin stock chip is or are coated with a high-barrier resin coating solution in an on-line coating manner, and the base film with the coating of the high-barrier resin coating solution is obtained after drying, horizontal stretching and heat setting, and the high-barrier polyester film is obtained. The oxygen transmissibility of the high-barrier polyester film is 6.0-12.3 cm /m *d*atm, the moisture transmissibility is 6.1-10.5 g/m *d, and the high-barrier polyester film is particularly applicable to the field of package.