Reinforcing Poly(e-caprolactone) nanofibers with cellulose nanocrystals
We studied the use of cellulose nanocrystals (CNXs) obtained after acid hydrolysis of ramie cellulose fibers to reinforce poly(e-caprolactone) (PCL) nanofibers. Chemical grafting with low-molecular-weight PCL diol onto the CNXs was carried out in an attempt to improve the interfacial adhesion with t...
| Autores: | , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2009 |
| País: | España |
| Institución: | Universitat Politècnica de Catalunya (UPC) |
| Repositorio: | UPCommons. Portal del coneixement obert de la UPC |
| Idioma: | inglés |
| OAI Identifier: | oai:upcommons.upc.edu:2117/335993 |
| Acceso en línea: | https://hdl.handle.net/2117/335993 https://dx.doi.org/10.1021/AM9003705 |
| Access Level: | acceso abierto |
| Palabra clave: | Cellulose Nanocrystals Cellulose nanocrystals Nanocrystalline cellulose Cellulose whiskers Surface grafting Electrospinning Fiber reinforcement Cel·lulosa Nanocristalls Àrees temàtiques de la UPC::Enginyeria dels materials |
| Sumario: | We studied the use of cellulose nanocrystals (CNXs) obtained after acid hydrolysis of ramie cellulose fibers to reinforce poly(e-caprolactone) (PCL) nanofibers. Chemical grafting with low-molecular-weight PCL diol onto the CNXs was carried out in an attempt to improve the interfacial adhesion with the fiber matrix. Grafting was confirmed via infrared spectroscopy and thermogravimetric analyses. The polymer matrix consisted of electrospun nanofibers that were collected as nonwoven webs. The morphology as well as thermal and mechanical properties of filled and unfilled nanofibers were elucidated by scanning electron microscopy, differential scanning calorimetry, and dynamic mechanical analysis, respectively. The addition of CNXs into PCL produced minimal changes in the thermal behavior of the electrospun fibers. However, a significant improvement in the mechanical properties of the nanofibers after reinforcement with unmodified CNXs was confirmed. Fiber webs from PCL reinforced with 2.5% unmodified CNXs showed ca. 1.5-fold increase in Young’s modulus and the ultimate strength compared to PCL webs. Compared to the case of grafted nanocrystals, the unmodified ones imparted better morphological homogeneity to the nanofibrillar structure. The grafted nanocrystals had a negative effect on the morphology of nonwoven webs in which individual nanofibers became annealed during the electrospinning process and, therefore, could not be compared to neat PCL nonwoven webs. A rationalization for the different effects of grafted and unmodified CNXs in reinforcing PCL nanofibers is provided. |
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