| Jazyk: |
angličtina |
| Rok vydání: |
2008 |
| Předmět: |
|
| Zdroj: |
eXPRESS Polymer Letters, Vol 2, Iss 12, Pp 885-889 (2008) |
| Druh dokumentu: |
article |
| ISSN: |
1788-618X |
| DOI: |
10.3144/expresspolymlett.2008.103 |
| Popis: |
Regenerated Bombyx mori silk fibers were spun from hexafluoro-iso- propanol solution of silk fibroin sponge in methanol used as a coagulant solvent and then elongated in water. The stress-strain curves of the regenerated fibers changed dramatically depending on the draw ratio and the structure was studied by 13C CP/MAS NMR and X-ray diffraction methods. The patterns of 13C CP/MAS NMR spectra of two regenerated fibers with different draw ratios (1× and 3×) and native silk fiber are all β-sheet structure although the fraction of random coil/distorted β-turn decreases in the order of 1×, 3× and native fiber gradually. On the other hand, azimuthal scans of their X-ray fiber patterns changed remarkably with increasing the draw ratio. This indicates that long-range orientation of the fibroin chain changes remarkably during the drawing process, but the short-range local structure does not change significantly. Regenerated silk fiber with a draw ratio of 3× is a fiber with high strength which is comparable with that of natural silk fiber. The regenerated fiber is also more degradable than natural silk fiber in enzyme solution in vitro. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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