Structural response of melt-spun poly(3-hydroxybutyrate) fibers to stress and temperature


Perret E., Reifler F. A., Gooneie A., Chen K., Selli F., Hufenus R.

POLYMER, vol.197, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 197
  • Publication Date: 2020
  • Doi Number: 10.1016/j.polymer.2020.122503
  • Journal Name: POLYMER
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Agricultural & Environmental Science Database, Biotechnology Research Abstracts, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Poly(3-hydroxybutyrate), Melt-spun fibers, X-ray diffraction, X-RAY-DIFFRACTION, MECHANICAL-PROPERTIES, ENZYMATIC DEGRADATION, CRYSTAL-STRUCTURE, STRAIN CURVES, BETA-FORM, FILMS, DEFORMATION, TRANSITION, INSIGHTS
  • Dokuz Eylül University Affiliated: No

Abstract

We have investigated the structural response of melt-spun poly-3-hydroxybutyrate (P3HB) fibers to stress and temperature and its impact on the mechanical properties. Low-stress (<= 1.6 MPa, 100-130 degrees C) annealed P3HB fibers showed a considerable viscoelastic behavior and remained ductile up to at least two months. Stress annealing with high weights (>= 32 MPa), however, lead to fibers with a higher tensile strength (182 MPa) and with a lower elongation at break (22%). These significant differences in the tensile properties are closely related to structural changes, which we have studied with in-situ wide-angle x-ray diffraction (WAXD) and small-angle x-ray scattering (SAXS) experiments. A highly oriented non-crystalline mesophase (P-nc), which is located in-between orthorhombic alpha-crystals is growing during high-stress annealing but disappears during low-stress annealing. However, it is possible to restore the mesophase by post-drawing. The viscoelastic hysteresis behavior of low-stress annealed fibers is explained by a reversible transformation of a-crystals into mesophase and back.