The global warming, depletion of fossil fuels, and environmental pollution by non-degradable plastics are major concerns of the world. For solutions of these problems, biomass-based plastics produced from renewable carbon sources as sugar, plant oil, and wood biomass, and biodegradable plastics that are completely degraded to water and carbon dioxide by the action of microorganisms should be developed for establishment of sustainable material society. Marine degradable fibers with both strength and elasticity were successfully fabricated by a new melt-spinning method from P(3HB-co-16mol%-4HB) that is one of microbial polyesters. Polymers was melted at the temperature lower than melting temperature to leave thick lamellar crystals and obtained fibers were stretched at room temperature. The molecular weight of fibers processed by this new melt-spinning method remained unchanged, suggesting that this new melt-spinning method is very effective for PHA, which has low thermal stability under the melting process. The obtained fibers have tensile strength of over 200 MPa and elongation at break of ca. 200% that are comparable to those of non-biodegradable elastic fibers processed from Polyethylene and Polypropylene. The elasticity is generated by changing the molecular structures of tie molecules between lamellar crystals and the free molecular chains in amorphous regions around stacked lamellae from helix structure to planar zigzag one. It was confirmed that these fibers were completely degraded by both seawater from Tokyo-Bay and freshwater from Sanshiro-Pond less than one month, and furthermore periodic stacked lamellar structures of ca. 0.5~1.0 mm that are consisted by at least 100 lamellae were confirmed by SEM observation. It was revealed that P(3HB-co-16 mol%-4HB) becomes high-performance biodegradable fibers with excellent mechanical properties and marine biodegradability.

Processing and structure analysis of marine degradable fibers with elasticity from poly[(R)-3-hydroxybutylate-co-4-hydroxybutylate] and evaluation of their environmental water degradability

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.