Mechanical properties of hydrated electrospun polycaprolactone (PCL) nanofibers.

Autor: Alharbi N; Department of Physics, Wake Forest University, Winston-Salem, NC, 27109, USA., Guthold M; Department of Physics, Wake Forest University, Winston-Salem, NC, 27109, USA; Center for Functional Materials, Wake Forest University, Winston-Salem, NC, 27109, USA. Electronic address: gutholdm@wfu.edu.
Jazyk: angličtina
Zdroj: Journal of the mechanical behavior of biomedical materials [J Mech Behav Biomed Mater] 2024 Jul; Vol. 155, pp. 106564. Date of Electronic Publication: 2024 Apr 27.
DOI: 10.1016/j.jmbbm.2024.106564
Abstrakt: Polycaprolactone (PCL) nanofibers are a promising material for biomedical applications due to their biocompatibility, slow degradation rate, and thermal stability. We electrospun PCL fibers onto a striated substrate with 12 μm wide ridges and grooves and determined their mechanical properties in an aqueous solution with a combined atomic force/inverted optical microscopy technique. Fiber diameters, D, ranged from 27 to 280 nm. The hydrated PCL fibers had an extensibility (breaking strain), ε max , of 137%. The Young's modulus, E, and tensile strength, σ T , showed a strong dependence on fiber diameter, D; decreasing steeply with increasing diameter, following empirical equations E(D)=(4.3∙10 3 ∙e -D51nm +1.1∙10 2 ) MPa and σ T (D)=(2.6∙10 3 ∙e -D55nm +0.6∙10 2 ) MPa. Incremental stress-strain measurements were employed to investigate the viscoelastic behavior of these fibers. The fibers exhibited stress relaxation with a fast and slow relaxation time of 3.7 ± 1.2 s and 23 ± 8 s and these experiments also allowed the determination of the elastic and viscous moduli. Cyclic stress-strain curves were used to determine that the elastic limit of the fibers, ε elastic , is between 19% and 36%. These curves were also used to determine that these fibers showed small energy losses (<20%) at small strains (ε < 10%), and over 50% energy loss at large strains (ε > 50%), asymptotically approaching 61%, as E loss =61%·(1-e -0.04*ε ). Our work is the first mechanical characterization of hydrated electrospun PCL nanofibers; all previous experiments were performed on dry PCL fibers, to which we will compare our data.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
Databáze: MEDLINE
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