New designs for vitrimer materials and vitrimer composites having enhanced mechanical, resilience and (re)processing properties – MATVIT

The main objectives of the MATVIT project are:
• To develop a new generation of vitrimer materials able to be reprocessed by injection or extrusion with higher throughput and offering better properties than current thermoset and thermoplastic materials.
• To understand the properties of vitrimers based on in-depth structural and mechanical characterizations.
• To demonstrate all the potential of vitrimer materials in key industrial applications using state-of-the-art processing and characterization techniques.
• To analyze innovation needs from the final market perspective, define the corresponding properties required from vitrimers, and propose appropriate solutions. The four independent and groundbreaking approaches that will be developed will help answering the industrial needs for reshapable, weldable and reprocessable high performance TSs.
• To disseminate the scientific results in scientific journals and conference and to promote vitrimer materials toward industrial partners (SMEs, large industrial groups and European technical centers) in order to make the outcome of MATVIT project sustainable.

IMP and MMC partners have developed new vitrimer formulations having high glass transition temperatures that are promising to be used as dynamic reprocessable matrices within long fiber composite materials. It has allowed reaching a better understanding of the viscoelastic properties of vitrimer materials at large. These results have resulted in four articles in good journals of the polymer community including two covers of Macromolecules and Polymer Chemistry journals. Besides, IMP and IPC partners have reached very promising results regarding the elabration of vitrimer-based thermplastic vulcanizates by reactive rocessing. These results are being currently explored further prior to valorization adn dissemination. Moreover, since the beginning of the MATVIT project, the IMP partner has been granted the coordination of an European Communitry funded innovative training network (ITN) project (https://www.vitrimat.eu/). This project has been granted three million euros and the two other MATVIT partners (MMC and IPC) are involved as beneficiary and partner organizations, respectively.

So far, the MATVIT project has opened significant prospects regarding the development of advanced vitrimer-based materials that should enable a better understanding of the structure/properties relationship of these materials to enable their use in cutting-edge applications (e.g. adhesives, thermosets and composites for consumer goods, construction, recreational, wind energy and automotive industries). This is particularly important since vitrimers bear the promise of next generation polymer materials and composites in line with sustainable development and requisites of the plastics circular economy.

A. Jourdain, M. M. Obadia, J. Duchet–Rumeau, J. Bernard, A. Serghei, F. Tournilhac, J.–P. Pascault, E. Drockenmuller “Comparison of PEG–based Networks Obtained by Cationic ROP of Neutral and 1,2,3–Triazolium Diepoxy Monomers” Polym. Chem. 2020, 11, 1894.
A. Jourdain, R. Asbai, O. Anaya, M. Chehimi, E. Drockenmuller, D. Montarnal “Rheological Properties of Covalent Adaptable Networks with 1,2,3-Triazolium Cross-links: the Missing Link Between Vitrimers and Dissociative Networks” Macromolecules 2020, 53, 1884.
Q.-A. Poutrel, J. J. Blaker, C. Soutis, F. Tournilhac, M. Gresil “Dicarboxylic acid-epoxy vitrimers: influence of the off-stoichiometric acid content on cure reactions and thermo-mechanical properties” Polym. Chem. 2020, 11, 5327.
A. Jourdain, O. Anaya, I. Antoniuk, H. Ben Romdhane, D. Montarnal, E. Drockenmuller “High-Tg poly(1,2,3-triazolium) covalent adaptable networks combining fast reprocessing and high temperature mechanical stability” submitted to Macromolecules.

MATVIT gathers a multidisciplinary consortium involving recognized researchers in the field of vitrimers (IMP and MMC) and the French technical center on plastics and composites (IPC). We propose two ground-breaking concepts to solve some technological locks preventing their widespread use and to widen their scope of application. The first concept consists in synthesizing polymer alloys by thoughtful and innovative combinations of vitrimer materials:
i) dual vitrimers involving two orthogonal exchange reactions in the same network, thus affording materials with widely tunable temperature-dependent viscosity profiles.
ii) vitrimer-based interpenetrating networks (VIPN) that can be reprocessed, consisting of two independent networks: a high Tg, slightly cross-linked covalent network and a dynamic vitrimer network.
iii) dynamic thermoplastic vitrimer vulcanizates (TPV²) resulting from the dispersion of a vitrimer phase into a minor continuous thermoplastic matrix.
The second concept consists in developing “pre-stressed vitrimer composites” from long fibers and high Tg vitrimer matrices. Careful choice of components and application of temperature and stress profiles will enable to prepare materials with embedded compressive stresses with enhanced mechanical strength.

The main objectives of the MATVIT project are:
• To develop a new generation of vitrimer materials able to be reprocessed by injection or extrusion with higher throughput and offering better properties than current thermoset and thermoplastic materials.
• To understand the properties of vitrimers based on in-depth structural and mechanical characterizations.
• To demonstrate all the potential of vitrimer materials in key industrial applications using state-of-the-art processing techniques.
• To analyze innovation needs from the final market perspective, define the corresponding properties required from vitrimers, and propose appropriate solutions. The four independent and groundbreaking approaches described above will help answering the industrial needs for reshapable, weldable and reprocessable high performance TSs.
• To disseminate the scientific results in scientific journals and conference and to promote vitrimer materials toward industrial partners (SMEs, large industrial groups and European technical centers) in order to make the outcome of MATVIT project sustainable.