It is a plastic whose properties can meet the requirements of use, remain unchanged during storage, and degrade into environmentally friendly substances in the natural environment after use. Therefore, it is also known as an environmental fully biodegradable material. The degradation process of degraded materials mainly includes biodegradation, photodegradation and chemical degradation. The degradation process mainly has synergistic effect, synergistic effect and synergistic effect. For example, photodegradation and oxide degradation often occur simultaneously and reinforce each other; Photodegradation is more likely to occur after photodegradation.