Life-like condensate networks formed by liquid crystal filaments

Liquid-liquid phase separation, whereby two liquids spontaneously demix, occurs in many important industrial and biological settings. Many such fluids exhibit liquid crystalline ordering, which can drive the formation of condensates with intriguing non-spherical shapes and dynamics. Here, we report the formation of filamentous condensate networks, which spontaneously assemble during the demixing of a mesogen from a solvent. Condensing mesogens form rapidly elongating filaments that link to form sparse ramified networks, which continuously remodel themselves with life-like dynamics. We use a combination of high-speed microscopy, theory, and simulations to study this networking process. We find that new linkages are predominantly formed by an apparently adhesive interaction between straight filaments, which snap into contact and rapidly wind into helical coils with spontaneously selected chirality. We make measurements of the bend modulus and surface tension to understand the conditions for network formation, which we modulate with cooing rate, confinement, and solvent composition. Understanding and controlling these dynamics may provide new avenues to direct pattern formation or template engineered and bio-inspired materials.