Layered double hydroxide/PBAT hybrid films with simultaneously high-barrier and degradable properties

Abstract

Inorganic-organic hybrid film with intriguing properties has attracted great attention. Herein, a hybrid film that sodium dodecyl sulfate (SDS) modified layered double hydroxides (LDH) integrated with poly (butylene adipate-co-terephthalate) (PBAT) matrix was rationally fabricated. The hydroxyl groups of LDH exhibit the “one-stone-two-birds” function that has good barrier and degradable properties on composite film. The trapped water by the hydroxyl group of LDH and 2D tortuous pathway efficiently inhibits the diffusion of water, thus contributing to largely decreased water vapor transmission rates (WVTR) and oxygen transmission rates (OTR) of SDS@LDH/PBAT film. The optimized SDS@LDH (5%)/PBAT composite film with 80 μm showed WVTR and OTR of 57.67 g/(m2·24 h·0.1 MPa) and 50.25 cm3/(m2·24 h·0.1 MPa), which improved ∼ 72% and ∼ 52%, compared with that of pure PBAT film. More significantly, the hydroxyl group served as scissors that can cleave the ester bond of PBAT, endowing the highly degradable property of the used hybrid film. And the plastic decomposed valuable chemicals and assembled LDH after decomposition can be feasibly recycled. This work, therefore, provides a new cognition of 2D material-based functional film, and offers a blueprint for green upcycling of plastic barrier films.