Impact of branching on the viscoelasticity of wormlike reverse micelles
(2012) In Soft Matter 8(42). p.10941-10949- Abstract
- We present an investigation on the effect of inter-micellar connections (branches) on the rheology of wormlike micelles. The system chosen is made of lecithin, minute amounts of water and organic solvents. Lecithin and water self-assemble into wormlike reverse micelles that can be branched or unbranched depending on the oil composition (and on the water content). In this respect, cyclohexane favours disconnected reverse micelles while isooctane promotes the formation of branches. By using mixtures of cyclohexane and isooctane as the oil phase and different water/lecithin ratios, the branch density of the system can be finely tuned. PGSE-NMR experiments allowed us to distinguish between branch-free (unbranched) and branched systems and the... (More)
- We present an investigation on the effect of inter-micellar connections (branches) on the rheology of wormlike micelles. The system chosen is made of lecithin, minute amounts of water and organic solvents. Lecithin and water self-assemble into wormlike reverse micelles that can be branched or unbranched depending on the oil composition (and on the water content). In this respect, cyclohexane favours disconnected reverse micelles while isooctane promotes the formation of branches. By using mixtures of cyclohexane and isooctane as the oil phase and different water/lecithin ratios, the branch density of the system can be finely tuned. PGSE-NMR experiments allowed us to distinguish between branch-free (unbranched) and branched systems and the response of the very same samples to mechanical stress was measured by rheology. This allows, for the first time, an experimental correlation between rheological properties and the presence of branches. It turned out that the presence of a few inter-micellar connections sensibly decreases the zero-shear viscosity measured in steady state flow curves. Comparison with oscillatory rheology experiments indicates that the main effect of branches is to shorten the terminal relaxation time by speeding-up the reptation. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3283281
- author
- Angelico, Ruggero ; Amin, Samiul ; Monduzzi, Maura ; Murgia, Sergio ; Olsson, Ulf LU and Palazzo, Gerardo
- organization
- publishing date
- 2012
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Soft Matter
- volume
- 8
- issue
- 42
- pages
- 10941 - 10949
- publisher
- Royal Society of Chemistry
- external identifiers
-
- wos:000310829400018
- scopus:84867385346
- ISSN
- 1744-6848
- DOI
- 10.1039/c2sm26528a
- language
- English
- LU publication?
- yes
- id
- f003d5ea-1b64-4f1e-b951-67be9a93a5b4 (old id 3283281)
- date added to LUP
- 2016-04-01 14:37:03
- date last changed
- 2022-01-28 01:36:01
@article{f003d5ea-1b64-4f1e-b951-67be9a93a5b4, abstract = {{We present an investigation on the effect of inter-micellar connections (branches) on the rheology of wormlike micelles. The system chosen is made of lecithin, minute amounts of water and organic solvents. Lecithin and water self-assemble into wormlike reverse micelles that can be branched or unbranched depending on the oil composition (and on the water content). In this respect, cyclohexane favours disconnected reverse micelles while isooctane promotes the formation of branches. By using mixtures of cyclohexane and isooctane as the oil phase and different water/lecithin ratios, the branch density of the system can be finely tuned. PGSE-NMR experiments allowed us to distinguish between branch-free (unbranched) and branched systems and the response of the very same samples to mechanical stress was measured by rheology. This allows, for the first time, an experimental correlation between rheological properties and the presence of branches. It turned out that the presence of a few inter-micellar connections sensibly decreases the zero-shear viscosity measured in steady state flow curves. Comparison with oscillatory rheology experiments indicates that the main effect of branches is to shorten the terminal relaxation time by speeding-up the reptation.}}, author = {{Angelico, Ruggero and Amin, Samiul and Monduzzi, Maura and Murgia, Sergio and Olsson, Ulf and Palazzo, Gerardo}}, issn = {{1744-6848}}, language = {{eng}}, number = {{42}}, pages = {{10941--10949}}, publisher = {{Royal Society of Chemistry}}, series = {{Soft Matter}}, title = {{Impact of branching on the viscoelasticity of wormlike reverse micelles}}, url = {{http://dx.doi.org/10.1039/c2sm26528a}}, doi = {{10.1039/c2sm26528a}}, volume = {{8}}, year = {{2012}}, }