Institut Charles Sadron Event

Soft polymer networks swollen in a large quantity of solvent known as gels are useful for diverse applications requiring a low elastic modulus (1 kPa to 1 MPa) and large deformability (strains > 100%). My research focuses on two classes of these materials. The first class is polyelectrolyte complex coacervates (PCC) formed upon an associative phase separation of oppositely-charged polyelectrolytes in water. We have investigated the phase behavior, viscoelasticity, nanostructure, and adhesive properties of (i) model PCC based on synthetic polyelectrolytes and (ii) bio-sourced PCC based on polysaccharides. Our work has highlighted the influence of several important parameters such as the real polymer concentration, the polymer persistence length, entanglements, and kinetic effects. The second class of materials is the so-called eutectogels, i.e. polymer gels swollen in deep eutectic solvents (DES). DES are an emerging class of green solvents formed via extensive hydrogen bonding at specific ratios of certain sugars, salts, and acids. Our work has elucidated DES-specific effects in tuning the dynamics and fracture behavior of eutectogels, enabling the design of soft, but dynamic and tough gels with a lower environmental footprint compared to the existing options. Moving forward, we aim to extend our investigations to more sophisticated polymer architectures and a broader library of solvents, enabling the informed design of functional soft polymer networks for diverse applications.