Abstract
Aerogels of cellulose exhibit remarkable mechanical properties as a function of density. Modifying the pore volume in classical cellulose aerogels using sacrificial template methods provide scaffold like microstructure. In the present study, we have developed aerogels of cellulose scaffolds having almost same density values but differ in microstructure and analysed the influence on the mechanical properties of bulk materials. This study can give an insight into the materials design for advanced engineering materials. Employing four surfactants having difference in hydrophilic-lipophilic balance (HLB), namely polyoxyethylene tert-octylphenyl ether (PT), polyoxyethylene (20) oleyl ether (PO), polyoxyethylene (40) nonylphenyl ether (PN) and polyoxyethylene (100) stearyl ether (PS), the cellulose scaffolds with hierarchical porous structures were developed. The mechanical properties of cellulose scaffolds were compared with classical pure cellulose aerogels. The results indicate that the solid fraction of cellulose nanofibers per unit volume of cell walls of scaffolds plays an important role in determining the elastic properties and strength. As the nanofibrils support the cell walls of scaffolds, Young’s modulus can be improved if the concentration of cellulose nanofibers is high at the cell walls or cell wall thickness is larger. The scaffold materials of this kind could be used as supporting materials with desired properties for filter, catalysis and biomedicine.

Highlights
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The aerogels of cellulose scaffolds with hierarchical porous structures were developed.
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The hierarchical porous structures were designed by using four different surfactants.
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The entrapped oil droplets in the cellulose matrix act as a structural template.
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The solid fraction per unit volume of cell walls of scaffolds influences the mechanical property.
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The structural design of pore channels play major role in defining the elastic property.
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Ganesan, K., Barowski, A., Ratke, L. et al. Influence of hierarchical porous structures on the mechanical properties of cellulose aerogels. J Sol-Gel Sci Technol 89, 156–165 (2019). https://doi.org/10.1007/s10971-018-4828-2
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DOI: https://doi.org/10.1007/s10971-018-4828-2
Keywords
- Cellulose
- Aerogel
- Scaffolds
- Hierarchical structure
- Porous network