The invention discloses a double-PHA barrier
system for a paper-based container and a
paperboard as well as a preparation method and application of the double-PHA barrier
system, and belongs to the technical field of paper-based material
surface engineering and green packaging. The
system sequentially comprises a paper base material, a water-based PHA dispersion hole sealing layer and a PHA
extrusion compact layer from inside to outside. According to the invention, the micron-sized PHA dispersoid without
cell debris is utilized, so that an efficient hole sealing effect which is difficult to achieve by a high
coating amount in a traditional process can be achieved by only needing an extremely low
coating amount, and the pinhole defect of an
extrusion layer is eliminated from the source. And in cooperation with the modified PHA
extrusion layer with the specific
crystallinity, the problem of micro-
cracking of a single
coating during edge rolling forming is cooperatively solved. According to the system, excellent barrier performance is achieved through a thinner bio-based structure, and meanwhile the system has a wide heat sealing window and excellent repulp recycling performance. Compared with the prior art, on the premise that high performance is guaranteed, the consumption amount of packaging materials and the environmental burden are remarkably reduced.