Description du projet
Des matériaux inspirés des muscles avec des propriétés améliorées
Les muscles sont caractérisés par une combinaison inégalée d’adaptabilité, de résistance mécanique et de souplesse. Les matériaux synthétiques inspirés des muscles naturels devraient trouver de nombreuses applications en robotique et en médecine. Les scientifiques du projet SAM, financé par l’UE, vont développer des matériaux de ce type à partir d’hydrogels sensibles aux stimuli (SRH, pour «stimuli-responsive hydrogels»), qui possèdent la capacité de changer de volume en réponse à la lumière ou à la température. Pour surmonter les problèmes de faible résistance mécanique associés aux SRH, les chercheurs combineront ces polymères avec des particules colloïdales offrant une capacité d’expansion et de contraction directionnelle. Le projet produira une plateforme permettant de synthétiser des matériaux peu coûteux et biocompatibles.
Objectif
The development of bioinspired materials that mimic animal muscles is a key step in the advancement of several scientific fields, including robotics and medicine. Muscles exhibit a unique combination of softness, mechanical resistance, adaptability and the ability to undergo large anisotropic deformations, which is so far unmatched in artificial materials. This action will develop a novel class of nanocomposite materials that mimic natural muscles by combining stimuli-responsive hydrogels (SRH) and colloidal liquid crystals (CLC).
SRHs consist of a network of stimuli-responsive polymer chains and a high fraction of water. By changing the solubility of the polymer with stimuli such as temperature and light it is possible to control the amount of water in the network, thereby producing large volumetric variations. SRHs are soft and shape-compliant actuating materials like muscles, but they generally exhibit poor mechanical resistance and the volumetric expansion has no preferential direction. These limitations will be overcome by attaching the stimuli-responsive polymer chains to anisotropic colloidal particles and assembling these building blocks in a uniaxially oriented manner like CLCs. The resulting nanocomposites will be soft, yet strong, capable of actuation-like conventional SRHs, and their expansion/contraction will be directional, thanks to the preferred orientation of the colloidal particles.
The proposed platform will rely on rod-like cellulose nanocrystals (CNCs) that will be decorated with cross-linkable poly-N-isopropylacrylamide chains bearing photoresponsive spiropyran units (poly-spiropyrans, PSPs). CNCs are inexpensive, biocompatible and can be easily extracted from renewable resources, while PSPs are known to form photoresponsive hydrogels. The combination of these elements and integration into uniaxially oriented structures will afford a novel class of soft actuators that will bring significant advancement to fields like robotics and medicine.
Champ scientifique
- natural scienceschemical sciencespolymer sciences
- engineering and technologynanotechnologynano-materialsnanocrystals
- engineering and technologyelectrical engineering, electronic engineering, information engineeringelectronic engineeringrobotics
- engineering and technologymaterials engineeringnanocomposites
- engineering and technologymaterials engineeringliquid crystals
Mots‑clés
Programme(s)
Régime de financement
MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF)Coordinateur
1700 Fribourg
Suisse