Liquid crystals

Liquid crystals (LCs) are viscoelastic soft materials known for their most famous use in displays (LCDs). LCs can also be processed into various composite films with new adjustable privacy, dimming and thermal insulation properties that improve visual and thermal comfort of inhabitants. For instance, Saint-Gobain owns SGG Priva-Lite®, a smart window made of micrometric LC droplets dispersed within a polymer matrix that switches from a hiding state to a transparent one when powered.

Privalite
SGG Priva-Lite® in the ON (top) and OFF (bottom) state.

At the laboratory, we aim at developing new approaches for the realization of smart windows that are based on the organization and optical properties of topological defects within colored composite matrices comprised of LCs, polymer networks, and plasmonic nanoparticles.

We are also currently coordinating the French National Research Agency (ANR) project Plasmoglaz through which we are collaborating with the Laboratoire de Physique de la Matière Condensée (LPMC) at Ecole Polytechnique in Palaiseau and the Centre de Recherche Paul Pascal (CRPP) in Pessac. The project focuses on composite materials made of plasmonic oxide nanoparticles and LCs for achieving new types of smart windows with adjustable solar control features.

In 2021, we are newly collaborating with the Laboratory Physique des Systèmes Complexes (PSC) in Amiens and the Laboratoire de Physique des Solides (LPS) in Orsay on a new type of LC composites.

See also in «Soft matter, liquid films, mixing granular materials»

Drying of thin films of complex liquids