Liquid Crystalline Composite Stabilized by Epoxy Polymer with Boscage‐Like Morphology for Energy‐Efficient Smart Windows with High Stability

Smart windows, which can provide comfortable indoor conditions for cars or buildings and protect the privacy of people, have attracted much attention. Traditional acrylate‐based smart windows have the disadvantages of high energy consumption and poor stability. Herein, an energy‐efficient smart window based on a liquid crystalline composite stabilized by an epoxy polymer with boscage‐like morphology is reported. This epoxy polymer is prepared by cationic polymerization of the liquid crystalline epoxy monomer E6M in vertically oriented negative nematic liquid crystals. The orientation of the liquid crystals is controlled by the epoxy polymer, which makes the composite film transparent and switchable to scattering by an electric field. Therefore, the composite film can be used in an energy‐efficient reverse‐mode smart window. The reverse‐mode smart window has better cycling stability than does acrylate, owing to the better mechanical properties endowed by the polymer matrix with a unique morphology and high stress tolerance. A liquid crystalline polymer with boscage‐like morphology is prepared through cationic polymerization of a liquid crystalline epoxy monomer in negative nematic liquid crystals. This unique polymer with boscage‐like morphology endows the liquid crystal‐polymer composite with reverse‐mode light‐regulating properties and better cycling stability than that from conventional acrylate‐based composite film due to its better mechanical property.