Poly (lactic acid)/Poly (butylene adipate-co-terephthalate) films with simultaneous high oxygen barrier and fast degradation properties

Although poly (lactic acid) (PLA) is a good environmentally-friendly bio-degradable polymer which is used to substitute traditional petrochemical-based polymer packaging films, the barrier properties of PLA films are still insufficient for high-barrier packaging applications. In this study, oxygen scavenger hydroxyl-terminated polybutadiene (HTPB) and cobalt salt catalyst were incorporated into the PLA/poly (butylene adipate-co-terephthalate) (PLA/PBAT), followed by melting extrusion and three-layer co-extrusion blown film process to prepare the composite films. The oxygen permeability coefficient of the composite film combined with 6 wt% oxygen scavenger and 0.4 wt% catalyst was decreased significantly from 377.00 cc·mil·m −2 ·day −1 ·0.1 MPa −1 to 0.98 cc·mil·m −2 ·day −1 ·0.1 MPa −1 , showing a remarkable enhancement of 384.69 times compared with the PLA/PBAT composite film. Meanwhile, the degradation behavior of the composite film was also accelerated, exhibiting a mass loss of nearly 60% of the original mass after seven days of degradation in an alkaline environment, whereas PLA/PBAT composite film only showed a mass loss of 32%. This work has successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior, which has great potential for high-demanding green chemistry packaging industries, including food, agricultural, and military packaging. A PLA/PBAT composite film containing oxygen scavenger HTPB and cobalt salt catalyst achieved simultaneous high oxygen barrier (a remarkable enhancement of 384.69 times) and fast degradation (a mass loss of nearly 60% after seven days in an alkaline environment) properties, which has great potential for high-demanding green chemistry packaging industries. • We have successfully prepared PLA/PBAT composite films with simultaneously improved oxygen barrier property and degradation behavior by introducing oxygen scavenger and catalyst. • The oxygen permeability coefficient was decreased significantly from 377.00 cc·mil·m −2 ·day −1 ·0.1MPa −1 to 0.98 cc·mil·m −2 ·day −1 ·0.1MPa −1 , showing a remarkable enhancement of 384.69 times. • The PLA/PBAT composite film exhibits a mass loss of nearly 60% of the original mass after seven days of degradation in an alkaline environment. • This work provides a feasible strategy to prepare a fast-degrading and high oxygen barrier PLA/PBAT composite film.