Suspension of size-controlled bubbles in a thermo-stimulable hydrogel: Stability and rheology
Foams or materials containing air bubbles are frequently used in everyday life, with applications ranging from cosmetics to enhanced oil recovery. The manufacturing of construction materials stands as one of the most prevalent examples of producing what are commonly known as aerated materials. For civil engineering applications, the addition of air bubbles leads to various improvements in the final product, such as: the use of less raw material, better thermal and/or acoustic insulation and reduced weight. More specifically, aerated complex materials are also used as templates for the production of metamaterials, which feature special acoustic properties due to their structure. One of the current challenges in setting up and manipulating these materials is to be able to modulate the rheological properties of the dispersed phase in a reversible way. For example, it is possible to inject air bubbles into a liquid phase, obtain a suspension of bubbles that can flow easily, and then freeze the bubbles in a gel matrix. The possibility of reversing the matrix from a liquid to a solid state is interesting for evacuating or transporting the system to a new functionality. It should be noted that the gel structure blocks the various destabilization mechanisms of air bubbles (drainage, ripening, coalescence)(1).
The aim of this project is to study the stability and rheology of foams and suspensions of air bubbles of controlled size inside a thermally stimulable gel phase. We will use the gel phase consisted of stearic and/or hydroxystearic acid (SA and/or HSA ), which in the presence of a counterion can be solubilized and self-assemble into different structures with different micelle/supramolecular assembly under temperature stimuli(2, 3). Bubbles of controlled size will be created using flow-focusing micro-fluidic systems, which allow rapid bubble production(4).
Involved laboratories: ICMPE – Clémence Le Coeur, Catherine Amiel, Alesya Mikhailovskaya; NAVIER – Florence Rouyer, Julie Goyon-Trohay. In collaboration with Fabrice Cousin (Laboratoire Léon Brillouin).
Expected skills: Background in Soft Matter, mechanics or physics. Previous experience in rheology and/or microfluidics is an advantage.
Duration: 1 year – Work start: within the end of 2023
Deadline: The selection will start in end of September 2023 and continue until a suitable candidate is appointed
Contact: send a CV including a list of publications and a motivation letter to clemence.le-coeur@cnrs.fr and florence.rouyer@univ-eiffel.fr
References
1. A.-L. Fameau et al., Angew. Chem. Int. Ed. 50, 8264–8269 (2011).
2. M. Almeida et al., Molecules. 28, 4336 (2023).
3. M. Almeida et al., Molecules. 28, 6317 (2023).
4. E. Lorenceau, Y. Y. C. Sang, R. Höhler, S. Cohen-Addad, Phys. Fluids. 18, 097103 (2006).