Efficient and precise outdoor lifetime prediction method for biodegradable poly (butylene adipate/ terephthalate) under various climate conditions

Outdoor lifetime prediction of a plastic gives the quantitative relationship between its service property and environmental factors, and is fundamental for efficient utilization and minimizing waste. However, it is still a major challenge after decades of great efforts. Poly (butylene adipate/terephthalate) (PBAT) has been widely used as biodegradable mulch films. Here we established a lifetime prediction method of PBAT under different climatic conditions. We established the quantitative correspondence of PBAT to environmental conditions by measuring CO₂ generation rates of PBAT under various combinations of temperature, solar irradiance, and humidity. A correlation between the CO₂ generation rate and the tensile strength of PBAT during outdoor aging is determined. Then, the lifetime prediction model of PBAT was built, showing the deterioration rates of tensile strength under various climate conditions. This model enables quantitative prediction of the space and time distribution of aging rates of PBAT in China, as well as quantitative comparison between any accelerated and natural aging. This work cut the time and money cost down greatly on lifetime prediction of PBAT, and facilitates the fine-tuning of PBAT stability based on the region of deployment. Moreover, this lifetime prediction method is a common strategy and can be used to other polymer materials for outdoor applications.