Mikto-grafted molecular brushes at liquid crystal-aqueous interfaces

Liquid crystal droplets in water (LCs emulsions) are a promising class of stimuli-responsive materials with potential applications in many areas of science and technology. In this work, dissipative particle dynamics (DPD) simulations were employed to elucidate how the architecture and surface concentration of mikto-grafted bottlebrush surfactants influence the structure and stability of LCs-water interfaces. Planar interface simulations revealed a monotonic decrease in interfacial tension with increasing surfactant concentration and sidechain length, while long backbones suppressed efficient interfacial packing and displayed reduced interfacial activity. LC droplets were also studied; simulations capture the tactoid shape characteristic of bare LC droplets observed experimentally. Simulations predict that, despite architectural differences, mikto-grafted bottlebrush adsorption does not disrupt nematic order in planar or droplet geometries, but can potentially stabilize LC emulsions. The findings reported here aim to help establish design rules for tuning interfacial tension and polymer conformation to develop long-lasting LC emulsions.