Missions

The researcher will carry out experimental studies and numerical simulations on the physical and physico-chemical phenomena of jets emitted by electrospinning, in order to envisage the production of nanofibrous materials on an industrial scale.

Activities

- Conduct a literature review to compare strategies for producing nanofibrous materials via electrospinning.
- Adapt an electrospinning pilot system to study different jet emission systems.
- Study the influence of process parameters (jet emission system geometry, voltage, etc.) on production throughput.
- Model the electro-hydrodynamic phenomena induced during processing using the finite element method.
- Characterize the fibrous membrane (mainly SEM analysis, thickness, deposited mass).
- Write publications and patents.

Skills

- The candidate must hold a PhD and have expertise in physics (fluid mechanics and/or electrostatics), polymer material science, and modeling.
- A very good level of French and English is required (please indicate TOEIC score or equivalent).
- Excellent communication skills are required.

Work Context

The work will be carried out at the Institute of Chemistry and Processes for Energy, Environment and Health (ICPEES UMR7515) as part of a collaborative project with MICHELIN company.
ICPEES context
The ICPEES is a joint research unit between the CNRS and the University of Strasbourg, with 150 people working in the fields of chemistry, materials and processes for applications related to energy, environment and health. The ICPEES research team involved in the project has been developing expertise in the synthesis and characterization of nanofibrous materials via the electrospinning process for over 10 years. The research aims at i) controlling the structuring of fibrous membranes, ii) developing eco-friendly strategies using only water as solvent and finally iii) functionalizing nanofibers for various applications such as biomedical, filtration or energy. The team has access to all the ICPEES resources (SEM, XPS, rheology, mechanical tests, electrical characterizations, surface property measurements, BET, etc…) to characterize the materials.
MICHELIN context
MICHELIN places innovation at the heart of its strategy, with a 2020 R&D budget of nearly €646 million, 10700 active patents, and 6000 people working in the field, including 3400 at the Ladoux site in France. The MICHELIN Group is undergoing a major transformation to contribute to innovation in the field of low environmental footprint materials and high-tech materials. The objectives are to make offerings and mobility more efficient and sustainable with new technologies, bio-based and recycled materials, zero-emission solutions as well as to position itself on new high-potential profitable growth markets such as flexible composites, medical applications, 3D metal printing and hydrogen mobility.
Project context
Electrospinning is a process used to fabricate polymer solutions subjected to the action of a strong electric field, enabling the production of nanofibrous materials. More specifically, at the laboratory scale, a polymer solution is delivered to a needle-shaped emitter electrode, which is subjected to an electrical potential of several tens of kilovolts. A liquid jet of the solution is emitted under the influence of the electric field induced between the emitter electrode and a counter-electrode, called the collector. As it travels through the air, the jet undergoes electro-hydro-dynamic instabilities, which promote jet stretching, solvent evaporation, and ultimately, the pseudo-random deposition of a polymer fiber onto the collector.
By adjusting the parameters of the polymer solution (viscosity, solvent nature, etc.) and the process parameters (electric potential, emitter-collector distance, etc.), it is possible to control the fiber diameter, typically between 100 nm and 1 micron. This process has reached a level of maturity that now allows for the industrial-scale production of nanostructured materials for various applications, such as nanofiber membranes for fuel cells, high-value-added composite materials, and biomaterials.
Intuitively, one approach to increasing production throughput is to multiply the number of emitter needles. However, due to electrostatic interactions, the throughput does not increase proportionally with the number of needles.
Thus, in this project, different strategies for the simultaneous emission of jets will be explored. The physical and physico-chemical phenomena that promote the simultaneous and dense emission of electrospinning jets will be studied experimentally, supported by numerical simulations, with the ultimate goal of increasing production throughput.

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

no specifics constraints