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Tailoring the self-assembly, interfacial properties and rheological behaviour of sugar-based surfactants

Larsson, Johan LU (2021)
Abstract
Surfactants are important ingredients in many formulated products used in everyday life. Many of these surfactants originates from fossil-based materials and degrades slowly in aquatic systems. As society strives towards having a smaller environmental footprint, surfactants that are non-toxic, biodegradable and can be synthesized from renewable raw materials need to be developed. To this end sugar-based surfactants, or alkylglycosides, is a promising class of surfactants that have the properties that are sought after. To utilize these surfactants to their full potential more knowledge is required about their behaviour both at interfaces and in solution.


In this thesis the behaviour of the alkylglycoside... (More)
Surfactants are important ingredients in many formulated products used in everyday life. Many of these surfactants originates from fossil-based materials and degrades slowly in aquatic systems. As society strives towards having a smaller environmental footprint, surfactants that are non-toxic, biodegradable and can be synthesized from renewable raw materials need to be developed. To this end sugar-based surfactants, or alkylglycosides, is a promising class of surfactants that have the properties that are sought after. To utilize these surfactants to their full potential more knowledge is required about their behaviour both at interfaces and in solution.


In this thesis the behaviour of the alkylglycoside C16G2, and how it is affected by small changes in its molecular structure, has been studied with scattering techniques and rheometry. The anomeric configuration was found to have a large impact as β-C16G2 allowed for a more efficient packing of the headgroup, compared to α-C16G2. This is apparent both at interfaces, where the adsorption was higher for the β anomer, and in solution, where β-C16G2 forms very elongated worm-like micelles while α-C16G2 forms shorter cylindrical micelles. The difference in self-assembly affects the rheological behaviour of these solutions where highly viscous, shear thinning and viscoelastic properties reflects the long micelles of β-C16G2, while solutions of α-C16G2 are Newtonian with low viscosity. The effect of introducing a double bond in the tailgroup of β-C16G2 was also investigated, where a significant decrease in Krafft point was seen, while the formation of worm-like micelles and viscous solutions was still evident. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Tanaka, Motomu, Heidelberg University, Kyoto University
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Sugar-based surfactants, Self-assembly, Scattering, Rheology, Adsorption, Sustainable materials
pages
169 pages
publisher
Lund University (Media-Tryck)
defense location
Sal A, Kemicentrum, Lund. Join via zoom: https://lu-se.zoom.us/j/68891125354
defense date
2021-01-29 09:00:00
ISBN
978-91-7422-777-2
978-91-7422-776-5
language
English
LU publication?
yes
id
7f569492-8b5e-4b67-a5f4-d709b858cff1
date added to LUP
2020-12-30 17:06:13
date last changed
2021-02-16 09:46:07
@phdthesis{7f569492-8b5e-4b67-a5f4-d709b858cff1,
  abstract     = {Surfactants are important ingredients in many formulated products used in everyday life. Many of these surfactants originates from fossil-based materials and degrades slowly in aquatic systems. As society strives towards having a smaller environmental footprint, surfactants that are non-toxic, biodegradable and can be synthesized from renewable raw materials need to be developed. To this end sugar-based surfactants, or alkylglycosides, is a promising class of surfactants that have the properties that are sought after. To utilize these surfactants to their full potential more knowledge is required about their behaviour both at interfaces and in solution.<br/><br/><br/>In this thesis the behaviour of the alkylglycoside C<sub>16</sub>G<sub>2</sub>, and how it is affected by small changes in its molecular structure, has been studied with scattering techniques and rheometry. The anomeric configuration was found to have a large impact as β-C<sub>16</sub>G<sub>2</sub> allowed for a more efficient packing of the headgroup, compared to α-C<sub>16</sub>G<sub>2</sub>. This is apparent both at interfaces, where the adsorption was higher for the β anomer, and in solution, where β-C<sub>16</sub>G<sub>2</sub> forms very elongated worm-like micelles while α-C<sub>16</sub>G<sub>2</sub> forms shorter cylindrical micelles. The difference in self-assembly affects the rheological behaviour of these solutions where highly viscous, shear thinning and viscoelastic properties reflects the long micelles of β-C<sub>16</sub>G<sub>2</sub>, while solutions of α-C<sub>16</sub>G<sub>2</sub> are Newtonian with low viscosity. The effect of introducing a double bond in the tailgroup of β-C<sub>16</sub>G<sub>2</sub> was also investigated, where a significant decrease in Krafft point was seen, while the formation of worm-like micelles and viscous solutions was still evident.},
  author       = {Larsson, Johan},
  isbn         = {978-91-7422-777-2},
  language     = {eng},
  publisher    = {Lund University (Media-Tryck)},
  school       = {Lund University},
  title        = {Tailoring the self-assembly, interfacial properties and rheological behaviour of sugar-based surfactants},
  url          = {https://lup.lub.lu.se/search/ws/files/89723213/Thesis_Johan_Larsson.pdf},
  year         = {2021},
}