The mechanical behavior of polylactic acid (PLA) films: fabrication, experiments and modelling

• Published in: Mechanics of time-dependent materials Vol. 25; no. 2; pp. 119 - 131
• Main Authors: Mirkhalaf, S. M., Fagerström, M.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2021; Springer Nature B.V
• Subjects: Applied Mechanics; Biomedical materials; Biopolymers; Characterization and Evaluation of Materials; Classical Mechanics; Composite materials; Constitutive models; Elasto-viscoplastic; Engineering; Maskinteknik; Mathematical models; Mechanical behavior; Mechanical behaviour; Mechanical Engineering; Mechanical properties; Polylactic acid; Polylactic acid (PLA); Polymer Sciences; Solid Mechanics; Strain; Teknisk mekanik; Thin films; Thin films; Mechanical behavior; Polylactic acid (PLA); Elasto-viscoplastic
• ISSN: 1385-2000; 1573-2738; 1573-2738
• DOI: 10.1007/s11043-019-09429-w

Polylactic acid (PLA) is one of the highly applicable bio-polymers in a wide variety of applications including medical fields and packaging. In order to quantitatively model the mechanical behavior of PLA and PLA based bio-composite materials, and also tailor new bio-composites, it is required to characterize the mechanical behavior of PLA. In this study, thin films of PLA are fabricated via hot-pressing, and tensile experiments are performed under different strain rates. To model the mechanical behavior, an elasto-viscoplastic constitutive model, developed in a finite strain setting, is adopted and calibrated. Using the physically-based constitutive model, all regimes of deformation under uniaxial stress state, including post-yield softening, were adequately captured in the simulations. Also, the rate dependency of the stress–strain behavior was properly modelled.