Structure control of lattice-patterned liquid crystals-polymer composites prepared by polarization-selective UV-curing through the addition of a fluorinated acrylate monomer

Abstract

The formation of lattice-patterned liquid crystal (LC)-polymer composites by polarization-selective ultraviolet (UV) curing of prepolymers containing cinnamate functional groups is known to be an effective method for controlling the interfacial properties between LC and polymer walls. However, due to the good miscibility of cinnamate functional groups with LC, phase separation between LC and prepolymers is insufficient, and challenges remain with regard to control of the phase separation structure. In this work, we focused on improving the phase separation behavior between LC and a prepolymer containing a photoreactive cinnamate oligomer by introducing a fluorinated acrylate monomer. The results showed that the larger difference in the solubility parameter between the fluorinated acrylate and LC improved the phase separation behavior between the LC and prepolymer, resulting in the fabrication of a more accurate and clear lattice structure of polymer walls. In addition, the introduction of a fluorinated acrylate monomer was found to slightly influence the control of the interaction between LC and polymer walls; this was verified by the decrease in driving voltage of LC-polymer composites. By using the fluorinated acrylate monomer as a component of prepolymers, control of the lattice structure and interfacial properties of polymer walls formed by polarization-selective UV curing becomes possible. (C) 2012 Elsevier B.V. All rights reserved.