Preparation of thermochromic cholesteric liquid crystal microcapsules with a planar alignment via stepwise interfacial polymerization

Abstract

Cholesteric liquid crystals (CLCs) have garnered significant attention due to their exceptional thermochromic properties and optical performance. However, the helical alignment of LC molecules becomes disordered during interfacial polymerization, primarily due to the interference of residual polymer monomers within the core, resulting in diminished optical properties. In this study, we propose a new method to completely consume the polymer monomers within the core through stepwise interfacial polymerization and promote a perfect planar arrangement of CLC molecules by exploiting the ordering properties of the smectic phase. Furthermore, we reduce scattering in microcapsule coatings by optimizing the particle size distribution and matching the refractive index of the system, thereby enhancing the clarity of the coatings and increasing reflectance. The prepared CLC microcapsules offer low production costs, scalability, and exceptional optical and thermochromic properties, which can be applied to smart decorative coatings, anti-counterfeit labels, and color-changing textiles.