High-porosity aerogels of high specific surface area prepared from nanofibrillated cellulose (NFC)

Sehaqui, Houssine; Zhou, Qi; Berglund, Lars A.

doi:10.1016/j.compscitech.2011.07.003

Cited by 491 publications

(371 citation statements)

References 28 publications

Supporting

Mentioning

339

Contrasting

Unclassified

Order By: Relevance

“…One feature of MFC is that it forms gel-like structures when suspended in water. After freeze-drying the material obtained can be characterized as highly porous aerogels or foams (Pääkkö et al 2008;Sehaqui et al 2010;Saito et al 2011;Sehaqui et al 2011). MFC may for example be prepared after a TEMPO-oxidation pretreatment (Saito et al 2006).…”

Section: Introductionmentioning

confidence: 99%

Reinforced absorbent material: a cellulosic composite of TEMPO-oxidized MFC and CTMP fibres

et al. 2012

View full text Add to dashboard Cite

This research aims to develop new materials based on renewable resources that can fulfill the functions necessary in the absorption core of a disposable diaper. Absorbent foam was recently produced from softwood kraft pulp by TEMPO oxidation, disintegration and freeze drying. In this study, the TEMPO-oxidized MFC was mixed with pulp fibres, thus forming a cellulosic composite, in an attempt to improve the mechanical stability of the freeze-dried absorbent material. The fibres were added in different amounts and the freeze-dried materials were evaluated for their absorption and retention properties. The results of this study suggest that the composite material has a better mechanical stability than the absorbent foam without fibres. It was shown that using spruce CTMP fibres in the composite resulted in better absorption and retention capacities than in a composite with softwood kraft pulp fibres. The higher stiffness of the CTMP fibres is a probable explanation for this difference. For the composite material with CTMP fibres, liquid porosimetry showed that pore size distribution was more or less retained when put under load. Furthermore, it was seen that the retention properties reached a maximum around 85 % CTMP fibres and 15 % TEMPO-oxidized MFC. In the centrifuge retention test, the retention of the TEMPO-oxidized MFC in the composite material reached about the same capacity as conventional superabsorbent polymers.

show abstract

Section: Introductionmentioning

confidence: 99%

Reinforced absorbent material: a cellulosic composite of TEMPO-oxidized MFC and CTMP fibres

et al. 2012

View full text Add to dashboard Cite

show abstract

“…In contrast to that, freeze-drying from tBuOH prevents the formation of ice crystals artifacts (Wheeler et al 1975) and is thus superior with regard to preserving the gel structure (Cai et al 2008). This freeze-drying method was also used to obtain aerogels with surface areas of 284-349 m 2 /g starting from cellulose nanofibrils (CNF) (Sehaqui et al 2011;Saito et al 2011;Nemoto et al 2015). Apart from freeze-drying, cellulose suspensions can be as well dried by airdrying or spray-drying (Peng et al 2012;Rämänen et al 2012;Ganesan et al 2016).…”

mentioning

confidence: 99%

Surface properties and porosity of highly porous, nanostructured cellulose II particles

et al. 2016

View full text Add to dashboard Cite

Recently, a new member of the nanocellulose family was introduced, a cellulose II gel consisting of nanostructured and spherical particles. In this study, we compared two different drying techniques to obtain highly porous powders from this gel with preserved meso-and macroporous nanostructure: first, freeze-drying after solvent exchange to tBuOH and second, supercritical drying of the respective EtOH alcogel. The approaches yielded aerogel powders with surface areas of 298 and 423 m 2 /g, respectively. Both powders are amphiphilic and possess energetically heterogeneous surfaces with dominating dispersive term of the surface energy in the range of 50-52 mJ/m 2 , as determined by a combination of physicochemical surface characterization techniques, such as iGC, BET and SEM. Despite the lower surface area, the cheaper and more widespread method, freeze-drying, yields a more polar and reactive cryogel.Keywords Nanocellulose Á Lyocell Á Inverse gas chromatography Á Thermoporosimetry Á Freezedrying Á Supercritical drying Abbreviations CNFCellulose nanofibrils FD Freeze-drying scCO 2 Supercritical CO 2 Electronic supplementary material The online version of this article

show abstract

“…Morphology of the aerogels studied with SEM Considering the low sensitivity of nitrogen sorption experiments to large pore sizes (Sehaqui et al 2011), the porosity of bagasse aerogels were further studied with SEM (Figs. 6, 7).…”

Section: Nitrogen Adsorption Analysismentioning

confidence: 99%

“…The preparation of lignocellulosic biomass aerogels were also achieved from wood solutions in 1-allyl-3-methylimidazolium chloride with cyclic freezingthawing process and supercritical CO 2 drying Lu et al 2012). Aerogels with high BET surface area are desirable in many industrial applications such as functional carriers (Sehaqui et al 2011). However, the reported lignocellulosic biomass aerogels suffered from low BET surface area, among which the highest one was only 122 m 2 /g (Aaltonen and Jauhiainen 2009; Li et al 2011;Lu et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Direct preparation of green and renewable aerogel materials from crude bagasse

Chen

Zhang

et al. 2016

Cellulose

View full text Add to dashboard Cite

Lignocellulosic biomass aerogels with relatively high Brunauer-Emmett-Teller (BET) surface area and pore volume were prepared directly from bagasse solutions in the present study. Bagasse was dissolved in DMSO/LiCl, treated with cyclic freezingthawing processes, and regenerated with water. The resulted bagasse hydrogels were solvent-exchanged to t-butanol and subjected to freeze-drying to obtain the lignocellulosic aerogels. The structure of the aerogels was studied with FTIR, nitrogen absorption, SEM, and XRD. The results showed that the aerogels had sheetlike skeletons interconnected with one another to form three-dimensional networks. The highest BET surface area and total pore volume of the aerogels were 185 m 2 /g and 0.46 cm 3 /g, respectively. By adjusting the concentration of bagasse solution in DMSO/LiCl, the structure of the aerogels could be controlled to some extent.

show abstract

High-porosity aerogels of high specific surface area prepared from nanofibrillated cellulose (NFC)

Cited by 491 publications

References 28 publications

Reinforced absorbent material: a cellulosic composite of TEMPO-oxidized MFC and CTMP fibres

Reinforced absorbent material: a cellulosic composite of TEMPO-oxidized MFC and CTMP fibres

Surface properties and porosity of highly porous, nanostructured cellulose II particles

Direct preparation of green and renewable aerogel materials from crude bagasse

Contact Info

Product

Resources

About