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- Ait Benhamou, Anass, et al.
(författare)
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Strong and Flame-Resistant Nanocellulose Sheets Derived from Agrowastes via a Papermaking-Assisted Process
- 2024
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Ingår i: acs applied polymer materials. - 2637-6105. ; 6:5, s. 2763-2776
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Tidskriftsartikel (refereegranskat)abstract
- In recent decades, the production of nanocellulose has gained significant attention. Nanocellulose-based film materials have found widespread applications in various high-end sectors owing to their remarkable characteristics. Nevertheless, the limitation of certain functional properties, such as resistance to water and fire, has posed challenges to their broader utilization. In this study, we conducted a comparative investigation on the impact of two distinct chemical modifications, namely, TEMPO-mediated oxidation and phosphorylation, on the production of nanocellulose sheets via a papermaking-assisted process. This approach explores the synergistic effects of these modifications in enhancing the properties of cellulose nanofibers for nanopaper production. To achieve this, we proposed utilizing Henna stems as an alternative source of cellulosic material, aiming to harness untapped agricultural residues as a sustainable alternative to conventional sources such as wood and cotton. The phosphorylated Henna nanopaper exhibited substantial enhancements in terms of mechanical properties, wettability, fire resistance, and water vapor permeability when compared to the TEMPO-modified Henna nanopaper. In conclusion, our findings underscore the potential of Henna stems as an environmentally sustainable source of cellulose for nanofiber production, positioning it as a promising alternative to wood and other lignocellulosic sources for advanced applications.
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| 2. |
- Kassab, Zineb, et al.
(författare)
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Production of cellulose nanofibrils from alfa fibers and its nanoreinforcement potential in polymer nanocomposites
- 2019
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Ingår i: Cellulose. - : SPRINGER. - 0969-0239 .- 1572-882X. ; 26:18, s. 9567-9581
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Tidskriftsartikel (refereegranskat)abstract
- Alfa fibers (Stipa Tenacissima) were effectively utilized in this study as a promising cellulose source for isolation of carboxy-functionalized cellulose nanofibrils (CNFs) using multiple treatments. Pure cellulose microfibers (CMFs) were firstly extracted by alkali and bleaching treatments. CNFs with an average nanofibrils diameter ranging from 1.4 to 4.6 nm and a crystallinity of 89% were isolated from CMFs by a combination of TEMPO-oxidation and mechanical disintegration processes. The morphology and physico-chemical properties of cellulosic materials were evaluated at different stages of treatments using several characterization techniques. Various CNF loadings (5-15 wt%) were incorporated into PVA polymer to evaluate the nanoreinforcement ability of CNFs and to produce CNF-filled PVA nanocomposite materials. The tensile and optical transmittance properties, as well as the morphological and thermal properties of the as-produced CNF-filled PVA nanocomposite films were investigated. It was found that the tensile modulus and strength of nanocomposites were gradually increased with increasing of CNF loadings, with a maximum increase of 90% and 74% was observed for a PVA nanocomposite containing 15 wt% CNFs, respectively. The optical transmittance was reduced from 91% (at 650 nm) for neat PVA polymer to 88%, 82% and 76% for PVA nanocomposites containing 5, 10 and 15 wt% CNFs, respectively. It was also found that the glass transition temperature was gradually increased from 76 degrees C for neat PVA to 89 degrees C for PVA nanocomposite containing 15 wt%. This study demonstrates the importance of Alfa fibers as annual renewable lignocellulosic material to produce CNFs with good morphology and excellent properties. These newly developed carboxy-functionalized CNFs could be considered as a potential nanofiller candidate for the preparation of nanocomposite materials of high transparency and good mechanical properties.Graphic abstract
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