Slow-Released Pbat/Pla Weeding Mulch Film with Nano-Halloysite-Loaded Glufosinate Ammonium: Fabrication, Enhanced Performance, and Weeding Mechanism

Improving the performance and giving new function of the poly (butylene adipate-co-terephthalate) (PBAT) based biodegradable mulch film have always been the research hotspots. However, the problems of translucent PBAT base film, which decreases in performance over time and is easily damaged by weeds, need to be solved. In this study, 11.17 wt.% of the commercial contact herbicide Glufosinate-ammonium (Glu) was loaded into the lumen of halloysite nanotubes (HNTs). The Glu-loaded HNTs (Glu@HNTs) and other treatment groups were further incorporated into PBAT/PLA composite films by melt blending and blow molding. Results demonstrated Glu, HNTs and Glu@HNTs dispersed uniformly in the composite films. Remarkably, while maintaining the original tensile strength of the film, the nominal strain of transverse fracture was increased by 19.6% to 51.2%, and the least water vapor transmission was reduced by 46.7% to 68.5%. Furthermore, the composite films added with Glu@HNTs can successfully kill the green bristlegrass and show a good slow-release effect, which can avoid the premature release of the herbicide before the weeds grow up. Overall, the combination of inorganic nano-fillers modified PBAT/PLA film and weeding has positive significance for reducing soil pollution and helping the long-term efficient use of biodegradable mulching.