Abstract text: The development of durable yet biodegradable materials for purposes such as food packaging, 3D printing filaments, or clothing remains a key issue. Conventional synthetic polymers sourced from petrochemicals often face trade-offs between cost, functionality, and environmental impact. Even renewable plastics such as polylactic acid (PLA) can still be recalcitrant to biodegradation under natural soil conditions.
To address these concerns, we explore the integration of sugar beet cellulose nanofibers, and potato starch into a PLA matrix. Whilst both of these have been extensively investigated for use as structural additives, the difficulties of mixing hydrophobic PLA with these hydrophilic biopolymer structures remains to be a significant obstacle that limits the effective amount of biopolymer that can be added to PLA or vice versa.
To manufacture our biocomposites, we grafted lactic acid monomers onto the surfaces of CNF and starch materials via aqueous Sn(Oct)2 graft copolymerization, varying the ratios of cellulose/starch/lactic acid. The resultant materials were characterised by FTIR, then casted into films that were studied for their tensile strengths, topology, and surface composition.
From this work we hope to maximise the content of CNF and starch within a PLA biocomposite material whilst maintaining or enhancing its original thermoplastic properties.