2025 AIChE Annual Meeting

(552g) Enhancing the Mechanical Performance of Poly(3-hydroxybutyrate) By Modifying Crystallinity through Additives

Authors

Julie Albert, Tulane University
Poly(3-hydroxybutyrate) (P3HB) is a biodegradable, semicrystalline polymer suitable for use in marine and terrestrial environments where it is degraded by natural microbial processes, typically within a few years. However, its high crystallinity (55-60%) causes brittleness and poor mechanical properties, which has hindered its widespread adoption for many applications. This research investigates strategies to adjust the crystallinity of P3HB, aiming to enhance mechanical properties through the incorporation of plasticizers, anti-aging agents, nucleating agents, and blending with other biodegradable polymers.

Modified materials were characterized using a comprehensive set of analytical techniques. Differential scanning calorimetry (DSC) and wide-angle x-ray scattering (WAXS) provided insights into crystallinity and phase behavior, while small-angle x-ray scattering (SAXS) was employed to elucidate the long-period associated with crystalline lamellae. Mechanical performance, primarily flexibility, durability, and brittleness, was evaluated using bending tests conducted on an Instron universal testing machine. Changes in viscosity and melting temperature were also noted during sample preparation, and processing methods were adjusted accordingly.

In general, additives enhanced the flexibility and durability of P3HB, while also improving processability. These findings demonstrate the potential for developing advanced, high-performance biodegradable polymer systems.