One-step microwave fabrication of waste potato-derived bifunctional film: sustainable mulch-fertilizer for plastic...

To address plastic pollution and food waste challenges, this study fabricated a biodegradable mulch film (FAPBMF) via microwave-driven crosslinking within 10 min using waste potato slurry (WPS), citric acid (CA) and fulvic acid (FA). Therein, their crosslinking via amidation, esterification, and hydrogen bonding played key roles in the film forming, showing an interpenetrating polymer network morphology. Thus, FAPBMF showed good tensile strength (23 % higher than polyethylene mulch film [PEF]), UV-shielding efficacy and FA sustained release (53.4 % release in 40 days). FAPBMF showed better growth-promoting, soil-amendment, and biosafety than PEF likely owing to its thermal/moisture retention and FA fertilization. A scale up test using a continuous microwave belt system proved its high commercialization potential. Economic analysis proved its cost-competitiveness against PEF and polylactic acid mulch film (PLAF) because of the enhanced on-site biodegradability. This work provided a minute-level one-step microwave-assisted strategy for transforming food waste into dual-functional biodegradable mulch film, which was beneficial for plastic pollution control and food waste recycling.