Environmental Stability and Its Improvement in Polymer/Liquid Crystal Hybrid Monolayer

Abstract

Host-guest hybrid monolayer films composed of an amphiphilic side chain azobenzene (Az) polymer and a low-molecular-mass liquid crystal (LC) were prepared on a solid substrate and the environmental stability was investigated. Hybrid Langmuir–Blodgett (LB) monolayer showed structural changes under conditions of vacuum or elevated temperature due to evaporation of the low mass LC molecule. The activation energy for the evaporation of 4’-pentyl-4-cyanobiphenyl (5CB) from the Az side chain array was estimated to be 104 kJ mol-1. Efforts were made to block the evaporation of LC by capping a transparent LB film barrier. Over-coated polymer LB films in the glassy state having a thickness exceeding 7 nm were capable of blocking evaporation of the LC molecule. This critical thickness was in consistent with the conditions to prepare a defect free ultrathin polymer resist.

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Ubukata, T., Seki, T. & Ichimura, K. Environmental Stability and Its Improvement in Polymer/Liquid Crystal Hybrid Monolayer. Polym J 33, 891–897 (2001). https://doi.org/10.1295/polymj.33.891

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Keywords

  • Hybrid Langmuir–Blodgett (LB) Film
  • Amphiphilic Polymer
  • Liquid Crystal
  • UV-VIS Absorption Spectroscopy
  • Fourier Transform Infrared (FT-IR) spectroscopy

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