{"title":"水合电纺聚己内酯(PCL)纳米纤维的机械性能。","authors":"Nouf Alharbi , Martin Guthold","doi":"10.1016/j.jmbbm.2024.106564","DOIUrl":null,"url":null,"abstract":"<div><p>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, <em>D</em>, ranged from 27 to 280 nm. The hydrated PCL fibers had an extensibility (breaking strain), <em>ε</em><sub>max</sub>, of 137%. The Young's modulus, <em>E</em>, and tensile strength, <span><math><mrow><msub><mi>σ</mi><mi>T</mi></msub></mrow></math></span>, showed a strong dependence on fiber diameter, <em>D</em>; decreasing steeply with increasing diameter, following empirical equations <span><math><mrow><mi>E</mi><mrow><mo>(</mo><mi>D</mi><mo>)</mo></mrow><mo>=</mo><mrow><mo>(</mo><mrow><mn>4.3</mn><mo>∙</mo><msup><mn>10</mn><mn>3</mn></msup><mo>∙</mo><msup><mi>e</mi><mrow><mo>−</mo><mfrac><mi>D</mi><mrow><mn>51</mn><mspace></mspace><mi>n</mi><mi>m</mi></mrow></mfrac></mrow></msup><mo>+</mo><mn>1.1</mn><mo>∙</mo><msup><mn>10</mn><mn>2</mn></msup></mrow><mo>)</mo></mrow></mrow></math></span> MPa and <span><math><mrow><msub><mi>σ</mi><mi>T</mi></msub><mrow><mo>(</mo><mrow><mi>D</mi><mo>)</mo><mo>=</mo><mo>(</mo><mn>2.6</mn><mo>∙</mo><msup><mn>10</mn><mn>3</mn></msup><mo>∙</mo><msup><mi>e</mi><mrow><mo>−</mo><mfrac><mi>D</mi><mrow><mn>55</mn><mspace></mspace><mi>n</mi><mi>m</mi></mrow></mfrac></mrow></msup><mo>+</mo><mn>0.6</mn><mo>∙</mo><msup><mn>10</mn><mn>2</mn></msup></mrow><mo>)</mo></mrow></mrow></math></span> 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, <em>ε</em><sub><em>elastic</em></sub>, is between 19% and 36%. These curves were also used to determine that these fibers showed small energy losses (<20%) at small strains (<em>ε</em> < 10%), and over 50% energy loss at large strains (<em>ε</em> > 50%), asymptotically approaching 61%, as <span><math><mrow><msub><mi>E</mi><mrow><mi>l</mi><mi>o</mi><mi>s</mi><mi>s</mi></mrow></msub><mo>=</mo><mn>61</mn><mo>%</mo><mo>·</mo><mrow><mo>(</mo><mrow><mn>1</mn><mo>−</mo><msup><mi>e</mi><mrow><mo>−</mo><mn>0.04</mn><mo>*</mo><mi>ε</mi></mrow></msup></mrow><mo>)</mo></mrow></mrow></math></span>. 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.</p></div>","PeriodicalId":380,"journal":{"name":"Journal of the Mechanical Behavior of Biomedical Materials","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1751616124001966/pdfft?md5=dc03fff80db02b94a0d224573d8010ad&pid=1-s2.0-S1751616124001966-main.pdf","citationCount":"0","resultStr":"{\"title\":\"Mechanical properties of hydrated electrospun polycaprolactone (PCL) nanofibers\",\"authors\":\"Nouf Alharbi , Martin Guthold\",\"doi\":\"10.1016/j.jmbbm.2024.106564\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>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, <em>D</em>, ranged from 27 to 280 nm. The hydrated PCL fibers had an extensibility (breaking strain), <em>ε</em><sub>max</sub>, of 137%. The Young's modulus, <em>E</em>, and tensile strength, <span><math><mrow><msub><mi>σ</mi><mi>T</mi></msub></mrow></math></span>, showed a strong dependence on fiber diameter, <em>D</em>; decreasing steeply with increasing diameter, following empirical equations <span><math><mrow><mi>E</mi><mrow><mo>(</mo><mi>D</mi><mo>)</mo></mrow><mo>=</mo><mrow><mo>(</mo><mrow><mn>4.3</mn><mo>∙</mo><msup><mn>10</mn><mn>3</mn></msup><mo>∙</mo><msup><mi>e</mi><mrow><mo>−</mo><mfrac><mi>D</mi><mrow><mn>51</mn><mspace></mspace><mi>n</mi><mi>m</mi></mrow></mfrac></mrow></msup><mo>+</mo><mn>1.1</mn><mo>∙</mo><msup><mn>10</mn><mn>2</mn></msup></mrow><mo>)</mo></mrow></mrow></math></span> MPa and <span><math><mrow><msub><mi>σ</mi><mi>T</mi></msub><mrow><mo>(</mo><mrow><mi>D</mi><mo>)</mo><mo>=</mo><mo>(</mo><mn>2.6</mn><mo>∙</mo><msup><mn>10</mn><mn>3</mn></msup><mo>∙</mo><msup><mi>e</mi><mrow><mo>−</mo><mfrac><mi>D</mi><mrow><mn>55</mn><mspace></mspace><mi>n</mi><mi>m</mi></mrow></mfrac></mrow></msup><mo>+</mo><mn>0.6</mn><mo>∙</mo><msup><mn>10</mn><mn>2</mn></msup></mrow><mo>)</mo></mrow></mrow></math></span> 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, <em>ε</em><sub><em>elastic</em></sub>, is between 19% and 36%. These curves were also used to determine that these fibers showed small energy losses (<20%) at small strains (<em>ε</em> < 10%), and over 50% energy loss at large strains (<em>ε</em> > 50%), asymptotically approaching 61%, as <span><math><mrow><msub><mi>E</mi><mrow><mi>l</mi><mi>o</mi><mi>s</mi><mi>s</mi></mrow></msub><mo>=</mo><mn>61</mn><mo>%</mo><mo>·</mo><mrow><mo>(</mo><mrow><mn>1</mn><mo>−</mo><msup><mi>e</mi><mrow><mo>−</mo><mn>0.04</mn><mo>*</mo><mi>ε</mi></mrow></msup></mrow><mo>)</mo></mrow></mrow></math></span>. 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.</p></div>\",\"PeriodicalId\":380,\"journal\":{\"name\":\"Journal of the Mechanical Behavior of Biomedical Materials\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.3000,\"publicationDate\":\"2024-04-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S1751616124001966/pdfft?md5=dc03fff80db02b94a0d224573d8010ad&pid=1-s2.0-S1751616124001966-main.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of the Mechanical Behavior of Biomedical Materials\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1751616124001966\",\"RegionNum\":2,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENGINEERING, BIOMEDICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the Mechanical Behavior of Biomedical Materials","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1751616124001966","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, BIOMEDICAL","Score":null,"Total":0}
Mechanical properties of hydrated electrospun polycaprolactone (PCL) nanofibers
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), εmax, of 137%. The Young's modulus, E, and tensile strength, , showed a strong dependence on fiber diameter, D; decreasing steeply with increasing diameter, following empirical equations MPa and 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, εelastic, 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 . 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.
期刊介绍:
The Journal of the Mechanical Behavior of Biomedical Materials is concerned with the mechanical deformation, damage and failure under applied forces, of biological material (at the tissue, cellular and molecular levels) and of biomaterials, i.e. those materials which are designed to mimic or replace biological materials.
The primary focus of the journal is the synthesis of materials science, biology, and medical and dental science. Reports of fundamental scientific investigations are welcome, as are articles concerned with the practical application of materials in medical devices. Both experimental and theoretical work is of interest; theoretical papers will normally include comparison of predictions with experimental data, though we recognize that this may not always be appropriate. The journal also publishes technical notes concerned with emerging experimental or theoretical techniques, letters to the editor and, by invitation, review articles and papers describing existing techniques for the benefit of an interdisciplinary readership.