Joséphine carried out her research in the P3R team at the Softmat laboratory, in close collaboration with Cnes and IRT Saint Exupéry.
On 5th of December, she defended her thesis entitled: “Vitrimer Matrix Composites for space applications”
Fiber-reinforced polymer composites are widely used in high-performance applications such as aerospace due to their excellent mechanical properties and processability. However, their reliance on thermosetting matrices presents a major limitation: once cured, these materials cannot be repaired, reshaped, or efficiently recycled, leading to significant manufacturing waste and end-of-life challenges.
This thesis investigates vitrimers as sustainable and high-performance alternatives to conventional thermosets. Vitrimer combines mechanical robustness of thermosets with the reprocessability and repairability of thermoplastics, offering a pathway toward a circular economy for advanced composites. The work establishes a complete workflow from fundamental material characterization to industrial processing and environmental validation.
The work first explores the fundamental chemistry and curing behavior of a disulfide-based vitrimer resin system. It demonstrates that a formulation with 20% amine excess enhances reactivity compared to the stoichiometric formulation. Time-Temperature-Transformation diagrams were developed to map curing kinetics and optimize processing windows. The increased content of dynamic disulfide bonds also improved reprocessability and reshaping capacity.
The thesis then adapts vitrimer matrices to industrial manufacturing techniques, particularly filament winding and prepreg production. Aerospace-grade properties (E = 300 GPa, σ = 1500 MPa) were achieved via composite cured via autoclave, while repair cycles reduced porosity from 27% to 4% in defective oven-cured composite. Also, the reshaping of defective components into new geometries was demonstrated, highlighting their potential for circular use. In parallel, vitrimer prepregs were successfully manufactured with consistent resin content (50%) and, a novel enduring prepreg, stable at room temperature, was developed, eliminating the need for cold storage. Vitrimers further proved their capacity to relax process-induced stresses, reducing curvature in asymmetric laminates by 50%.
Moreover, vitrimer composites were evaluated for space use through vacuum, irradiation, and thermal cycling tests. They showed low outgassing comparable to aerospace thermosets, resisted electron irradiation with Tg rising from 175 °C to 190 °C, but failed thermal cycling when cycle above Tg. Thus, Tg emerges as a critical design constraint.
Overall, this research validates vitrimer composites as viable, industrially processable, and environmentally resilient materials for aerospace, while also identifying Tg as a critical limitation. It establishes a comprehensive framework from chemistry to industrial application, positioning vitrimers as a transformative step toward next-generation sustainable composites.
Highlights of the thesis:
- Joséphine gave oral presentations in many conferences (ICCM24, IMP Days 2024, 30 ans de l’ICT in 2024 , COMET Matériaux & Structures in 2024, COMET Matériaux & durabilité in 2023) and won an award for her oral presentation at the Journées GFP Sud-Ouest 2024;
- an article about her work is published in the journal ACS Applied Polymer Materials.
Many congratulations to Joséphine for the quality of her work!