Composites of carbon nanofibers and thermoplastic polyurethanes with shape-memory properties prepared by chaotic mixing
Composites of carbon nanofibers (CNFs), oxidized car bon nanofibers (ox-CNFs), and shape-memory thermo plastic polyurethane (TPU) were prepared in a chaotic mixer and their shape-memory properties evaluated. The polymer was synthesized from 4,40 -diphenylme thane diisocyanate, 1,4-butanediol chai...
| Autores Principales: | Jimenez, Guillermo A., Jana, Sadhan C. |
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| Formato: | Artículo |
| Idioma: | Inglés |
| Publicado: |
Wiley Inter Science
2022
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| Materias: | |
| Acceso en línea: |
http://hdl.handle.net/11056/23028 https://doi.org/10.1002/pen.21442 |
| Sumario: |
Composites of carbon nanofibers (CNFs), oxidized car bon nanofibers (ox-CNFs), and shape-memory thermo plastic polyurethane (TPU) were prepared in a chaotic
mixer and their shape-memory properties evaluated.
The polymer was synthesized from 4,40
-diphenylme thane diisocyanate, 1,4-butanediol chain extender, and
semicrystalline poly(e-caprolactone) diol soft segments.
The shape-memory action was triggered by both con ductive and resistive heating. It was found that soft
segment crystallinity and mechanical reinforcement by
nanofibers produced competing effects on shape memory properties. A large reduction in soft segment
crystallinity in the presence of CNF and stronger me chanical reinforcement by well-dispersed ox-CNF
determined the shape-memory properties of the re spective composites. It was found that the maximum
shape recovery force, respectively, 3 and 4 MPa, was
obtained in the cases of 5 and 1 wt% CNF and ox-CNF,
respectively, compared with 1.8 MPa for unfilled TPU.
The degree of soft segment and hard segment phase
separation and thermal stability of the composites
were analyzed. POLYM. ENG. SCI., 49:2020–2030, 2009.
ª 2009 Society of Plastics Engineers |
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