Advancing sustainable agriculture: a novel multi-layer film approach to plastic mulching

Biodegradable plastic mulch films (BMFs) have been used in agriculture as an alternative to conventional polyethylene mulches, offering benefits such as reduced labor costs and in-soil biodegradability. However, BMFs often degrade slowly, and fragments remain in the soil for multiple years. This study introduces a novel multi-layer agricultural mulch film (MLAMF) with poly(butylene adipate-co-terephthalate) (PBAT) outer layers and a thermoplastic starch (TPS) core, designed to enhance biodegradation and reduce plastic accumulation. In laboratory composting (LC), the MLAMF achieved 64% mass loss over 365 days, while pure PBAT films degraded by only 12%. In industrial composting (IC) conditions, the MLAMF and PBAT films showed 58% and 33% mass loss in 14 days, respectively. Respirometry tests indicate that the presence of TPS accelerates mineralization relative to the monolayer film. A small scale field trial revealed no statistically significant differences in onion yield or rot incidence between MLAMF and the commercial films.