Self-healing vitrimer composites for soft robotics

Jakob Langenbach (1) , Camille Bakkali-Hassani (1) , Quentin-Arthur Poutrel (1) , Antonia Georgopoulou (2, 3) , Frank Clemens (2) , Francois Tournilhac (4, 1) , Sophie Norvez (1)

1 C3M - Chimie Moléculaire, Macromoléculaire et Matériaux (UMR7167)
2 EMPA - Swiss Federal Laboratories for Materials Science and Technology [Dübendorf]
3 VUB - Vrije Universiteit Brussel
4 MMC - Laboratoire Matière Molle et Chimie

Hybrid networks (i.e. including physical and chemical crosslinks) were synthesized from bio-sourced fatty acids, linked to each other by a controlled number of non-exchangeable ether bonds, exchangeable ester bonds and non-covalent hydrogen bonds. Mechanical properties are tuned by the acid/epoxy ratio. Their thermo-stimulated weldability was exploited to incorporate stretchable strain sensors by embedding electrically conductive fibers into the vitrimer matrix. The efficiency of welding at 80 °C and the tunability of mechanical properties are both attractive assets for effective incorporation of thermo-degradable conductive fibers while preserving their mechanical and electrical integrity. Mechanical and electrical behavior of the sensor composites were simultaneously tested in cyclic tensile experiments at 50 °C. The stress concentration in dog-bone shaped samples was investigated by observations in polarized light and shear stress calculations. The study emphasizes the importance of matching the Young’s moduli of components in deformable composite samples, which is important for soft robotic applications.

Domaines: Chimie; Sciences de l'ingénieur [physics]

Jakob Langenbach, Camille Bakkali-Hassani, Quentin-Arthur Poutrel, Antonia Georgopoulou, Frank Clemens, et al.. Self-healing vitrimer composites for soft robotics. Composites Meet Sustainability – 20th European Conference on Composite Materials, ECCM20., Jun 2022, Lausanne (CH), Switzerland. pp.239, ⟨10.5075/epfl-298799_978-2-9701614-0-0⟩. ⟨hal-04237515⟩