Nematic Colloids at Liquid Crystal-Air Interfaces via Photopolymerization

Liquid crystals (LCs) have been shown to control the organization and location of colloidal assemblies ranging from chain-like to hexagonal structures. Most systems that exploit LC-mediated assembly for producing colloidal superstructures require the use of pre-synthesized particles or temperature-induced phase separation. Here, we demonstrate simultaneous synthesis and assembly of colloidal assemblies at LC-air interfaces. Polymer colloids are produced by photopolymerization of an acrylate monomer mixed in a non-reactive liquid crystal. Colloids spontaneously form ordered assemblies that cover the entire area of the LC-air interfaces. Systematic experiments varying the reaction time were conducted to monitor the growth and assembly. Our results demonstrate the design rules for producing nematic colloids at LC interfaces via photopolymerization which can offer opportunities for the preparation of large-scale LC-templated interfacial superstructures.