Biodegradable PPC-PBS multilayered barrier film and preparation method thereof

The invention discloses a biodegradable high-performance PPC-PBS (Poly(Propylene Carbonate)-Poly(Butylene Succinate)) multilayered barrier film. The multilayered barrier film is characterized by being prepared from the following constituents: modified light calcium carbonate, PPC, a chain extender and PBS, wherein the mass ratio of modified light calcium carbonate to PPC is (1-20):100; the mass ratio of the chain extender to PPC is (0.1-3):100; the total mass ratio of PBS to PPC, the chain extender and modified nanometer calcium carbonate is (10-100):100. The high-performance PPC-PBS multilayered film is simple in preparation technology and very suitable for industrial production; meanwhile, the raw materials for preparing the film are accessible; according to the high-performance PPC-PBS multilayered film disclosed by the invention, under the condition that the film thickness is invariable, the film layers can be regulated to obtain the multilayered film, the number of layers of which is 2-2048, and the thickness of the single layer of the film is up to nanometer scale; the tensile strength, the tearing strength, the elongation at break and the oxygen barrier property of the multilayered film can be improved, and meanwhile, the multilayered film is completely biodegradable.