Journal Article

IMPULSE-2026-00122

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png A novel stretching method for enhancing the toughness of PHBV films

Gallet-Pandellé, A. ; Chaléat, C. ; Colwell, J. ; Garvey, C.MLZ* ; Pratt, S. ; Lant, P. ; Laycock, B. (Corresponding author)

2026
Elsevier Science Oxford

Please use a persistent id in citations: doi:10.1016/j.polymer.2026.130545

Abstract: Polyhydroxyalkanoates (PHAs) are a family of biobased and biodegradable polymers gaining attention as environmentally friendly alternatives to conventional plastics. However, the inherent brittleness of the common poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) limits its widespread use. This work explores a novel method whereby solvent-cast PHBV films are stretched in the presence of residual solvent to improve their toughness. Tensile testing and wide angle X-ray scattering (WAXS) were used to study changes in mechanical properties and crystalline morphology. This new stretching method significantly enhanced mechanical performance, increasing elongation at break from 2% in unstretched films to values consistently above 50%, and in some cases exceeding 200% at low draw ratios. The ultimate tensile strength increased linearly with the draw ratio, from 30 to 130 MPa. Accordingly, the toughness was always above 20 MJ m-3 and exceeded 70 MJ m-3 for some stretching conditions. WAXS revealed that these improvements were due to a high degree of chain alignment and the introduction of the metastable β-form crystalline phase. This method may provide a simple approach to improve the toughness of PHBV films without chemical modification.

Keyword(s): Engineering, Industrial Materials and Processing (1st) ; Soft Condensed Matter (2nd) ; Industrial Application (2nd)

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Contributing Institute(s):

1. SOFTMATTER (SOFTMATTER)
2. TOFTOF (TOFTOF)

Experiment(s):

1. No specific instrument

Appears in the scientific report 2026

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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