Biodegradation Behavior of Poly (Lactic Acid) (PLA), Poly (Butylene Adipate-Co-Terephthalate) (PBAT), and Their Blends Under Digested Sludge Conditions

This paper presents a study on the degradation of Poly (lactic acid) (PLA), Poly (butylene abdicate—terephthalate) (PBAT) and their blends with different proportions in the environment of digested sludge. The degradation rates of PLA and PBAT were obtained through anaerobic reaction device. The samples obtained at regular intervals were measured and analyzed by differential scanning calorimeter (DSC), infrared spectrometer (FTIR) and scanning electron microscope (SEM) respectively. The results showed that the degradation rate of PLA was higher than that of PBAT under the same degradation environment and degradation time. DSC results showed that the degradation rate of PLA in the amorphous phase was slowed by the influence of PBAT. The characteristic peaks of the materials on the infrared spectrum shifted after degradation which implicit the degradation occurs. At the microscopic level, numerous protruding ribs in the material can be seen in the electron micrograph. Obviously, the samples can be degraded under the environment of digested sludge.