Cellulose nanofibril foams are cellulose-based porous materials with outstanding mechanical properties, resulting from the high strength-to-weight ratio of nanofibrils. Here we report the development of an optimized fabrication process for highly porous cellulose foams, based on a well-controlled freeze-thawing-drying (FTD) process at ambient pressure. This process enables the fabrication of foams with ultra-high porosity, up to 99.4%, density of 10 mg/cm3, and liquid (such as oil) absorption capacity of 100 L/kg. The proposed approach is based on the ice-templating of nanocellulose suspension in water, followed by thawing in ethanol and drying at environmental pressures. As such, the proposed fabrication route overcomes one of the major bottle-necks of the classical freeze-drying approach, by eliminating the energy-demanding vacuum drying step required to avoid wet foam collapse upon drying. As a result, the process is simple, environmentally friendly, and easily scalable. Details of the foam development fabrication process and functionalization are thoroughly discussed, highlighting the main parameters affecting the process, e.g., the concentration of nanocellulose and additives used to control the ice nucleation. The foams are also characterized by mechanical tests and oil absorption measurements, which are used to assess the foam absorption capability as well as the foam porosity. Compound water-in-oil drop impact experiments are used to demonstrate the potential of immiscible liquid separation using cellulose foams

Antonini, C., Wu, T., Zimmermann, T., Kherbeche, A., Thoraval, M., Nyström, G., et al. (2019). Ultra-Porous Nanocellulose Foams: A Facile and Scalable Fabrication Approach. NANOMATERIALS, 9(8) [10.3390/nano9081142].

Ultra-Porous Nanocellulose Foams: A Facile and Scalable Fabrication Approach

Antonini, Carlo
Primo
;
2019

Abstract

Cellulose nanofibril foams are cellulose-based porous materials with outstanding mechanical properties, resulting from the high strength-to-weight ratio of nanofibrils. Here we report the development of an optimized fabrication process for highly porous cellulose foams, based on a well-controlled freeze-thawing-drying (FTD) process at ambient pressure. This process enables the fabrication of foams with ultra-high porosity, up to 99.4%, density of 10 mg/cm3, and liquid (such as oil) absorption capacity of 100 L/kg. The proposed approach is based on the ice-templating of nanocellulose suspension in water, followed by thawing in ethanol and drying at environmental pressures. As such, the proposed fabrication route overcomes one of the major bottle-necks of the classical freeze-drying approach, by eliminating the energy-demanding vacuum drying step required to avoid wet foam collapse upon drying. As a result, the process is simple, environmentally friendly, and easily scalable. Details of the foam development fabrication process and functionalization are thoroughly discussed, highlighting the main parameters affecting the process, e.g., the concentration of nanocellulose and additives used to control the ice nucleation. The foams are also characterized by mechanical tests and oil absorption measurements, which are used to assess the foam absorption capability as well as the foam porosity. Compound water-in-oil drop impact experiments are used to demonstrate the potential of immiscible liquid separation using cellulose foams
Articolo in rivista - Articolo scientifico
ambient pressure drying; cellulose nanomaterials; compound drops; foam; freeze-drying; freeze-thawing; hydrophobicity; ice-templating; nanofibrils; oil absorption
English
2019
9
8
1142
open
Antonini, C., Wu, T., Zimmermann, T., Kherbeche, A., Thoraval, M., Nyström, G., et al. (2019). Ultra-Porous Nanocellulose Foams: A Facile and Scalable Fabrication Approach. NANOMATERIALS, 9(8) [10.3390/nano9081142].
File in questo prodotto:
File Dimensione Formato  
Antonini et al (2019) Ultra-Porous Nanocellulose Foams A Facile and Scalable Fabrication Approach.pdf

accesso aperto

Tipologia di allegato: Publisher’s Version (Version of Record, VoR)
Dimensione 4 MB
Formato Adobe PDF
4 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/240460
Citazioni
  • Scopus 51
  • ???jsp.display-item.citation.isi??? 45
Social impact