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Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels.

Chinga-Carrasco G, Syverud K - J Biomater Appl (2014)

Bottom Line: The pre-treatments yielded a highly nanofibrillated material, with significant amounts of aldehyde and carboxyl groups.This is due to the swelling capacity of the 3D micro-porous structures, which have ionisable functional groups.In this study, we demonstrated that nanocellulose gels have a significantly higher swelling degree in neutral and alkaline conditions, compared to an acid environment (pH 3).

View Article: PubMed Central - PubMed

Affiliation: Paper and Fibre Research Institute (PFI) - Høgskoleringen 6b, Trondheim, Norway gary.chinga.carrasco@pfi.no.

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Freeze-dried structures of carboxymethylated pre-treated samples. (a) The freeze-dried structures without (left) and with Ca2+ (right) are exemplified. (b) FESEM of the micro-porous structure of the carboxymethylated nanocellulose sample. (c) FESEM of the micro-porous structure of the carboxymethylated nanocellulose, which is ionic-bonded with Ca2+. FESEM: field-emission scanning electron microscopy.
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fig5-0885328214531511: Freeze-dried structures of carboxymethylated pre-treated samples. (a) The freeze-dried structures without (left) and with Ca2+ (right) are exemplified. (b) FESEM of the micro-porous structure of the carboxymethylated nanocellulose sample. (c) FESEM of the micro-porous structure of the carboxymethylated nanocellulose, which is ionic-bonded with Ca2+. FESEM: field-emission scanning electron microscopy.

Mentions: According to Czaja et al.,21 the creation of a moist environment, the ability to control fluid loss and the absorption of exudates are important characteristics of a modern wound dressing. Such characteristics can be related to the porous structure and surface chemistry of the material. The porous structure of the CMNC sample is exemplified in Figure 5. Note the structure composed of pores in the micrometer scale (Figure 5(b) and (c)). The pores are defined by walls, which are composed of self-assembled cellulose nanofibrils.15 The CMNC sample, which was made in the presence of Ca2+, was smaller and apparently denser than the neat CMNC sample (Figure 5(a)). This is most probably due to the ionic links between the COO− groups and the Ca2+, which increased the cross-linking density and reduced the swelling capacity of the gel.Figure 5.


Pretreatment-dependent surface chemistry of wood nanocellulose for pH-sensitive hydrogels.

Chinga-Carrasco G, Syverud K - J Biomater Appl (2014)

Freeze-dried structures of carboxymethylated pre-treated samples. (a) The freeze-dried structures without (left) and with Ca2+ (right) are exemplified. (b) FESEM of the micro-porous structure of the carboxymethylated nanocellulose sample. (c) FESEM of the micro-porous structure of the carboxymethylated nanocellulose, which is ionic-bonded with Ca2+. FESEM: field-emission scanning electron microscopy.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2 - License 3
Show All Figures
getmorefigures.php?uid=PMC4231171&req=5

fig5-0885328214531511: Freeze-dried structures of carboxymethylated pre-treated samples. (a) The freeze-dried structures without (left) and with Ca2+ (right) are exemplified. (b) FESEM of the micro-porous structure of the carboxymethylated nanocellulose sample. (c) FESEM of the micro-porous structure of the carboxymethylated nanocellulose, which is ionic-bonded with Ca2+. FESEM: field-emission scanning electron microscopy.
Mentions: According to Czaja et al.,21 the creation of a moist environment, the ability to control fluid loss and the absorption of exudates are important characteristics of a modern wound dressing. Such characteristics can be related to the porous structure and surface chemistry of the material. The porous structure of the CMNC sample is exemplified in Figure 5. Note the structure composed of pores in the micrometer scale (Figure 5(b) and (c)). The pores are defined by walls, which are composed of self-assembled cellulose nanofibrils.15 The CMNC sample, which was made in the presence of Ca2+, was smaller and apparently denser than the neat CMNC sample (Figure 5(a)). This is most probably due to the ionic links between the COO− groups and the Ca2+, which increased the cross-linking density and reduced the swelling capacity of the gel.Figure 5.

Bottom Line: The pre-treatments yielded a highly nanofibrillated material, with significant amounts of aldehyde and carboxyl groups.This is due to the swelling capacity of the 3D micro-porous structures, which have ionisable functional groups.In this study, we demonstrated that nanocellulose gels have a significantly higher swelling degree in neutral and alkaline conditions, compared to an acid environment (pH 3).

View Article: PubMed Central - PubMed

Affiliation: Paper and Fibre Research Institute (PFI) - Høgskoleringen 6b, Trondheim, Norway gary.chinga.carrasco@pfi.no.

Show MeSH
Related in: MedlinePlus