Aquatic biodegradation of poly(β-hydroxybutyrate) in polylactic acid and maleic anhydride blended fibers

• Published in: Journal of polymer research Vol. 31; no. 4
• Main Authors: Kwon, Soojin, Zambrano, Marielis C., Pawlak, Joel J., Ford, Ericka, Venditti, Richard A.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-04-2024; Springer Nature B.V
• Subjects: Biodegradation; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Compatibilizers; Fibers; Industrial Chemistry/Chemical Engineering; Maleic anhydride; Melt spinning; Miscibility; Original Paper; Polylactic acid; Polymer Sciences; Polymers; Biodegradation; Bio-based polymer blending; Microplastic; Phase separation
• ISSN: 1022-9760; 1572-8935
• DOI: 10.1007/s10965-024-03930-8

In this study PLA and PHB were melt-blended with/without maleic anhydride (MA) as a compatibilizer and melt-spun into a monofilament. The aquatic biodegradation of PLA/PHB fibers was tracked regarding the PLA and PHB components and the total carbon in the blend. Pure PLA fiber was recalcitrant to aquatic biodegradation in the present conditions, whereas PHB was readily degradable, as expected. The 75/25% and 50/50% PLA/PHB fibers showed zero biodegradation. The 25/75% PLA/PHB blend showed only an 11% final biodegradation extent and a 13% PHB biodegradation extent. It is shown that an unintended consequence of blending PLA with PHB is that after biodegradation, micro/nano plastic pollution is evolved. MA increased the miscibility, which further decreased the PHB biodegradation. The lower biodegradation extent with MA indicates that increased miscibility and more intimate coverage of the biodegradable polymer with the unbiodegradable polymer may have a negative effect on the biodegradation of biodegradable polymers.