Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • 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
Conductive biofoams of wheat gluten containing carbon nanotubes, carbon black or reduced graphene oxide
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.ORCID iD: 0000-0002-7674-0262
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.ORCID iD: 0000-0002-2230-3059
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.ORCID iD: 0000-0002-0236-5420
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
Show others and affiliations
2017 (English)In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 7, no 30, p. 18260-18269Article in journal (Refereed) Published
Abstract [en]

Conductive biofoams made from glycerol-plasticized wheat gluten (WGG) are presented as a potential substitute in electrical applications for conductive polymer foams from crude oil. The soft plasticised foams were prepared by conventional freeze-drying of wheat gluten suspensions with carbon nanotubes (CNTs), carbon black (CB) or reduced graphene oxide (rGO) as the conductive filler phase. The change in conductivity upon compression was documented and the results show not only that the CNT-filled foams show a conductivity two orders of magnitude higher than foams filled with the CB particles, but also that there is a significantly lower percolation threshold with percolation occurring already at 0.18 vol%. The rGO-filled foams gave a conductivity inferior to that obtained with the CNTs or CB particles, which is explained as being related to the sheet-like morphology of the rGO flakes. An increasing amount of conductive filler resulted in smaller pore sizes for both CNTs and CB particles due to their interference with the ice crystal formation before the lyophilization process. The conductive WGG foams with CNTs were fully elastic with up to 10% compressive strain, but with increasing compression up to 50% strain the recovery gradually decreased. The data show that the conductivity strongly depends on the type as well as the concentration of the conductive filler, and the conductivity data with different compressions applied to these biofoams are presented for the first time.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2017. Vol. 7, no 30, p. 18260-18269
Keywords [en]
Carbon black, Carbon nanotubes, Compaction, Crude oil, Fillers, Graphene, Nanotubes, Pore size, Solvents, Yarn, Compressive strain, Conductive fillers, Conductive Polymer, Electrical applications, Orders of magnitude, Percolation thresholds, Reduced graphene oxides, Reduced graphene oxides (RGO), Foams
National Category
Polymer Technologies
Identifiers
URN: urn:nbn:se:kth:diva-207441DOI: 10.1039/c7ra01082fISI: 000399005500011Scopus ID: 2-s2.0-85016468994OAI: oai:DiVA.org:kth-207441DiVA, id: diva2:1098139
Note

Funding details: EIT, European Institute of Innovation and Technology; Funding details: 243-2011-1436, Svenska Forskningsrådet Formas; Funding text: This work was financed by the Swedish Research Council Formas (No. 243-2011-1436). R. L. Andersson acknowledges the support from: European Institute of Innovation and Technology (EIT)-KIC InnoEnergy, Swedish Centre for Smart Grids and Energy Storage (SweGRIDS) and ABB AB.

QC 20170523

Available from: 2017-05-23 Created: 2017-05-23 Last updated: 2017-11-29Bibliographically approved
In thesis
1. Biofoams and Biocomposites based on Wheat Gluten Proteins
Open this publication in new window or tab >>Biofoams and Biocomposites based on Wheat Gluten Proteins
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Novel uses of wheat gluten (WG) proteins, obtained e.g. as a coproduct from bio-ethanol production, are presented in this thesis. A flame-retardant foam was prepared via in-situ polymerization of hydrolyzed tetraethyl orthosilicate (TEOS) in a denatured WG matrix (Paper I). The TEOS formed a well-dispersed silica phase in the walls of the foam. With silica contents ≥ 6.7 wt%, the foams showed excellent fire resistance. An aspect of the bio-based foams was their high sensitivity to fungi and bacterial growth. This was addressed in Paper II using a natural antimicrobial agent Lanasol. In the same paper, a swelling of 32 times its initial weight in water was observed for the pristine WG foam and both capillary effects and cell wall absorption contributed to the high uptake. In Paper III, conductive and flexible foams were obtained using carbon-based nanofillers and plasticizer. It was found that the electrical resistance of the carbon nanotubes and carbon black filled foams were strain-independent, which makes them suitable for applications in electromagnetic shielding (EMI) and electrostatic discharge protection (ESD). Paper IV describes a ‘water-welding’ method where larger pieces of WG foams were made by wetting the sides of the smaller cubes before being assembled together. The flexural strength of welded foams was ca. 7 times higher than that of the same size WG foam prepared in one piece. The technique provides a strategy for using freeze-dried WG foams in applications where larger foams are required.

Despite the versatile functionalities of the WG-based materials, the mechanical properties are often limited due to the brittleness of the dry solid WG. WG/flax composites were developed for improved mechanical properties of WG (Paper V). The results revealed that WG, reinforced with 19 wt% flax fibres, had a strength that was ca. 8 times higher than that of the pure WG matrix. Furthermore, the crack-resistance was also significantly improved in the presence of the flax.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2017. p. 98
Series
TRITA-CHE-Report, ISSN 1654-1081 ; 2017:30
Keywords
Wheat gluten, biofoam, biocomposite, freeze-drying, flame-retardant, silica, antimicrobial, bimodal, conductive biofoam, flax fiber, crack-resistance
National Category
Polymer Technologies
Research subject
Chemistry
Identifiers
urn:nbn:se:kth:diva-207778 (URN)978-91-7729-453-5 (ISBN)
Public defence
2017-08-25, F3, Lindstedtsvägen 26, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Swedish Research Council Formas, 243-2011-1436
Note

QC 20170524

Available from: 2017-07-14 Created: 2017-05-23 Last updated: 2017-07-14Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records BETA

Wu, QiongAndersson, Richard L.Peuvot, KevinNilsson, FritjofHedenqvist, Mikael S.Olsson, Richard T.

Search in DiVA

By author/editor
Wu, QiongSundborg, HenrikAndersson, Richard L.Peuvot, KevinGuex, LeonardNilsson, FritjofHedenqvist, Mikael S.Olsson, Richard T.
By organisation
Polymeric MaterialsFibre and Polymer Technology
In the same journal
RSC Advances
Polymer Technologies

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 115 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • 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