Effectively translating the promising properties of boron nitride nanotubes (BNNTs) into macroscopic assemblies has vast potential for applications, such as thermal management materials and protective fabrics against hazardous environment. We spun fibers from aqueous dispersions of BNNTs in polyvinyl alcohol (PVA) solutions by a wet spinning method. Our results demonstrate that BNNTs/PVA fibers exhibit enhanced mechanical properties, which are affected by the nanotube and PVA concentrations, and the coagulation solvent utilized. Compared to the neat PVA fibers, we obtained roughly 4.3-, 12.7-, and 1.5-fold increases in the tensile strength, Young's modulus, and toughness, respectively, for the highest performing BNNTs/PVA fibers produced from dispersions containing as low as 0.1 mass% of nanotube concentration. Among the coagulation solvents tested, we found that solvents with higher polarity such as methanol and ethanol generally produced fibers with improved mechanical properties, where the fiber toughness shows a strong correlation with solvent polarity. These findings provide insights into assembling BNNTs-based fibers with improved mechanical properties for developing unique applications.
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Antiplasticizing Behaviors of Glucarate and Lignin Bio‐Based Derivatives on the Properties of Gel‐Spun Poly(Vinyl Alcohol) Fibers
Petrol and biochemical plasticizers are added to poly(vinyl alcohol) (PVA) to improve its processability while tuning its moisture sensitivity. But those additives often reduce the mechanical performance of PVA products. In this study, the antiplasticization and properties of PVA containing additives from biorenewable sources are studied. PVA fibers are gel‐spun having up to 3 wt% glucarate salts and 30% lignin. Glucarate lowers the gel melting temperature of PVA and increases fiber draw ratio. Further, glucarate enhances the mechanical performance of PVA beyond that of neat fibers. Interestingly, the combination of lignin and glucarate causes phase separation among fiber—a PVA/glucarate phase as the fiber core and lignin/PVA phase as the fiber shell. Neat PVA partially dissolves in 85 °C water; whereas, fibers containing glucarate and/or lignin resist dissolution. Thus, the combination of glucarate and lignin can induce high strength and moisture resistance, which are desirable industrial fiber properties.
more » « less- NSF-PAR ID:
- 10053450
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Materials and Engineering
- Volume:
- 303
- Issue:
- 4
- ISSN:
- 1438-7492
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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