About the seminar:

Commercial biopolymer poly(lactic acid) (PLA) is a potential carbon storage material in soil due to its resistance to microbial attack. However, the investigation of degradability of biological production of PLA homopolymer has not been reported. Thus, it remains unclear how bio-produced PLA degrades in soil and how its molecular structure-property relationships influence this process. Numerous studies have investigated the degradation of PLA-based materials in soil under both natural and controlled conditions. Some focused on morphological changes, while others employed analytical techniques to track changes in molecular structure and properties. These studies concluded that commercial PLA showed either no degradation or insignificant changes in soil under both conditions. In contrast, poly(lactic acid) as a copolymer with poly(hydroxy butyrate), synthesized by genetically modified bacteria, has been shown to fully degrade. Although this report provides insights into bacterial PLA, the degradation matrix was ocean water – not soil. This motivates the need for biological production of PLA homopolymer, especially from plants, and investigation of its degradability in soil under natural conditions. This seminar will discuss the analytical techniques used in PLA degradation studies, address open questions, and introduce approaches for characterizing bio-produced PLA as a candidate for carbon storage.