Preparation and characteristics of biodegradable mulching films based on fermentation industry wastes

• Biodegradable mulching film (BMF) was prepared from citric acid fermentation wastes.
• BMF has excellent mechanical and degradation properties.
• The water vapor barrier property of BMF was improved.
• BMF had positive effects on soil quality in the process of agricultural application.
• BMF is an alternative available to traditional plastic film.

To solve the serious environmental pollution caused by both fermentation industry wastes and traditional plastic mulching film, a novel biodegradable mulching film (BMF), based on the combination of hydrogen peroxide (H2O2) oxidation and polyvinyl alcohol (PVA) polymeric modification technologies, was prepared from citric acid fermentation wastes (CAFW). The tensile strength (TS) and elongation at break (%E) of BMF could reach 16.43 MPa and 446.96% respectively at oxidant concentration of 4% (w/v) and CAFW/PVA ratio of 70/30. Meanwhile, the water vapor barrier properties of BMF were improved. In the soil covering test, BMF degradation and increased soil temperatures and moisture were achieved, which lead to effectively improving crops growth, soil microbial community structure and soil enzyme activities. Finally, after 80 days of degradation, the weight loss of BMF reached 72.6%. These results indicated that the degradation performance of BMF could facilitate crops growth in different growing periods.