Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Transparent and Flexible Nacre‐Like Hybrid Films of Aminoclays and Carboxylated Cellulose Nanofibrils
Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK). Wallenberg Wood Science Center, Sweden.
Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK). Wallenberg Wood Science Center, Sweden.ORCID iD: 0000-0002-5702-0681
2018 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, no 27, article id 1703277Article in journal (Refereed) Published
Abstract [en]

Nacre and other biological composites are important inspirations for the design and fabrication of multifunctional composite materials. Transparent, strong, and flexible hybrid films of aminoclays (AC) and carboxylated cellulose nanofibrils (CNF) with a nacre‐like microstructure at AC contents up to 60 wt% are prepared. The high transmittance of visible light is attributed to the high homogeneity of the hybrid films and to the relatively small refractive index contrast between the CNF‐based matrix and synthetic AC. The strength and strain to failure of the hybrids are significantly higher than biogenic nacre and other nacre‐mimicking nanocellulose‐based materials, e.g., montmorillonite‐CNF and graphene oxide‐CNF composite films. The excellent mechanical properties are related to the ionic bonds between the negatively charged carboxylic groups on the CNF and the positively charged amine groups on the AC nanoparticles. This work illustrates the significance of tailoring the interactions between small clay particles and biopolymers in multifunctional materials with potential applications as printable barrier coatings and substrates for optoelectronics.

Place, publisher, year, edition, pages
2018. Vol. 28, no 27, article id 1703277
Keywords [en]
aminoclays, hybrid films, nacre mimics, nanocellulose, transparency
National Category
Chemical Sciences
Research subject
Materials Chemistry
Identifiers
URN: urn:nbn:se:su:diva-155264DOI: 10.1002/adfm.201703277ISI: 000436929400004OAI: oai:DiVA.org:su-155264DiVA, id: diva2:1198275
Available from: 2018-04-17 Created: 2018-04-17 Last updated: 2019-12-16Bibliographically approved
In thesis
1. Nanocellulose-based materials: from colloidal assembly to functional films
Open this publication in new window or tab >>Nanocellulose-based materials: from colloidal assembly to functional films
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The assembly of nature-based nanomaterials into complex architectures is both a design principle of biological composites, e.g., wood and nacre with outstanding properties and a promising route for developing functional macroscopic materials. This thesis aims to investigate and understand the colloidal and self-assembly behaviour of nanocellulose in aqueous dispersions. Moreover, composite films of nanocellulose and nanoclay/lignin with diverse functionalities, e.g., mechanical and optical properties, are fabricated by tailoring the electrostatic interactions of these building blocks.

The evaporation induced assembly of sulfonated cellulose nanocrystal (CNC) has been followed in either an aqueous droplet on substrates or a levitated droplet by real-time small angle X-ray scattering. The evolution of structural features, e.g., an isotropic phase, biphasic phase, fully liquid crystalline and contracted helical structures of drying CNC dispersions were related to the power-law scaling of the particle separation distance (d) with concentrations (c, from 1 vol% to 38 vol%). Below 2 vol%, CNC dispersions consolidated isotropically with a scaling of d c-1/3, while the fully cholesteric liquid crystalline phase showed a unidimensional contraction of the nematic structure (d c-1) with increasing concentrations. Competition between gelation and the ordered assembly of CNC was quantitatively evaluated in nanoscale for the first time, which was reflected by a scaling of d c-2/3.

The rheology of composite dispersions of carboxylated cellulose nanofibril (CNF) and nanoclay was investigated, which was influenced by the surface charge of CNF, the morphology of nanoclays and interactions between CNF and clay particles. Optically transparent films of synthetic aminoclay (50 wt%) and CNF were fabricated, of which tensile strength and strain to failure (205 MPa and 7.5%) were significantly higher than those of nacre and other nacre-mimicking nanocellulose-based materials, e.g., montmorillonite-CNF films, due to the formation of ionic bonding between the cationic clay and anionic CNF.

Lignin nanoparticles were testified to enhance the colloidal stability and dispersity of carboxylated CNF in dispersions, and showed a remarkable strengthening and stiffening effect on the matrix of CNF. The mechanical properties of lignin-CNF films were superior to previously reported polymer/nanoparticle-CNF composites, such as polyvinyl alcohol-CNF films and even reduced graphene oxide-CNF films.

Place, publisher, year, edition, pages
Stockholm: Department of Materials and Environmental Chemistry, Stockholm University, 2018. p. 63
National Category
Materials Chemistry
Research subject
Materials Chemistry
Identifiers
urn:nbn:se:su:diva-155267 (URN)978-91-7797-248-8 (ISBN)978-91-7797-249-5 (ISBN)
Public defence
2018-06-07, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B, Stockholm, 13:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.

Available from: 2018-05-15 Created: 2018-04-17 Last updated: 2019-08-14Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Search in DiVA

By author/editor
Liu, YingxinBergström, Lennart
By organisation
Department of Materials and Environmental Chemistry (MMK)
In the same journal
Advanced Functional Materials
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 680 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf