Study on the composting degradation of plastic films by alkali pretreatment

Abstract Aiming at the problem of slow degradation of PBAT/PLA degradable plastics in the natural environment, a degradation enhancement strategy based on the synergistic effect of alkaline pretreatment and composting was proposed. The PBAT/PLA films under different treatment conditions were placed in a high-temperature composting system for 120 days of degradation experiments. The morphological changes, hydrophilicity evolution, and molecular structure degradation process of the film samples were systematically analyzed by combining scanning electron microscopy, infrared spectroscopy, ultraviolet spectroscopy, contact angle test, and other methods. At the same time, multiple functional microorganisms were isolated and the degradation ability verification experiment was carried out. The results showed that alkaline pretreatment significantly increased the degradation rate of the film samples, the mass loss rate and hydrophilicity change were greater than those of the control group, and the ester bond rupture and functional group changes were obvious. In the microbial test, Aspergillus fumigatus showed strong degradation ability. The study showed that the synergistic effect of alkaline pretreatment and composting can effectively improve the biodegradation efficiency of PBAT/PLA films, providing technical support for the terminal disposal of degradable plastics.