Surfaces, Interfaces, Colloids

This course presents the concepts, fundamentals, and orders of magnitude of the physics and physical chemistry of interfaces that govern the mesoscopic scale of matter and ultimately determine the behavior and properties of everyday objects: soil, milk, cheese, paints, inks, cosmetics, adhesives, lubricants, etc., as well as numerous technological processes and biological cells and membranes.

Understand the microscopic physical origin of colloidal interactions and be able to evaluate their intensities and ranges in relation to thermal agitation energy: For example, know how to calculate the van der Waals interaction energy between objects of simple geometric shapes, or the range of interactions between charged surfaces in water as a function of ionic strength.

- Know how to characterize a colloidal state: nature of the dispersion, specific surface area, sedimentation length, diffusion coefficient, etc.

- Correctly estimate the numerical values of the various physical quantities relevant to the mesoscopic scale and know how to express them in units appropriate to this scale.

- Understand the different types of surfactant molecules and how they self-assemble: calculate critical micelle concentration and know how to characterize it experimentally.

- Know how to solve simple exercises related to mooring statics.

Basic knowledge of general physics (thermodynamics, electrostatics, forces, energy, fundamentals of quantum mechanics), thermochemistry, and mastery of basic mathematical tools for physics (derivatives, integrals, limited developments, cylindrical and spherical coordinates).

Final exam

The colloidal state: description, time, energy, and length scales

Intermolecular interactions: covalent interactions, Coulomb interactions, dipole interactions, se interactions

Van der Waals interaction between colloids

Electrostatic forces between surfaces in liquids.

Polymer-mediated steric forces

Colloidal stability: DLVO theory. Coagulation kinetics.

Physicochemistry of self-assembly and surfactants

Wetting phenomena: surface and interfacial tension, wetting criterion, spreading parameter, capillary length, Young-Dupré law, Laplace law, Jurin law, tensiometry.

Chemical equilibria and free enthalpy

Acid-base, oxidation-reduction, solubility, and complexation equilibria.

Preparation of colloidal suspensions?