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Title: Melt-Spun Nanocomposite Fibers Reinforced with Aligned Tunicate Nanocrystals
The fabrication of nanocomposite films and fibers based on cellulose nanocrystals (P-tCNCs) and a thermoplastic polyurethane (PU) elastomer is reported. High-aspect-ratio P-tCNCs were isolated from tunicates using phosphoric acid hydrolysis, which is a process that affords nanocrystals displaying high thermal stability. Nanocomposites were produced by solvent casting (films) or melt-mixing in a twin-screw extruder and subsequent melt-spinning (fibers). The processing protocols were found to affect the orientation of both PU hard segments and the P-tCNCs within the PU matrix and therefore the mechanical properties. While the films were isotropic, both the polymer matrix and the P-tCNCs proved to be aligned along the fiber direction in the fibers, as shown using SAXS/WAXS, angle-dependent Raman spectroscopy, and birefringence analysis. Tensile tests reveal that fibers and films, at similar P-tCNC contents, display Young’s moduli and strain-at-break that are within the same order of magnitude, but the stress-at-break was found to be ten-times higher for fibers, conferring them a superior toughness over films.  more » « less
Award ID(s):
1844463
PAR ID:
10140633
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Polymers
Volume:
11
Issue:
12
ISSN:
2073-4360
Page Range / eLocation ID:
1912
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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