Reflection Image Enhacement Using Alkylated Imidazolium Ionic Liquid

Abstract

The retaining reflection color developed from the photonic crystals has been current interest. As the volatile solvents evaporated very quickly, reflecting colors from the photonic crystals disappeared with in one day. Some ionic liquids can permeate in between the polymer photonic crystal layers. Block copolymers, such as the polystyrene-b-poly-2-vinylpyridine (PS-b-P2VP), have been used to obtain photonic crystals. The molecular weight of PS-b-P2VP and the hydrophobicity of the ionic liquids were varied to attain persistent color from the photonic crystals. The imidazolium and the 1-ethyl-3-methylimidazolium were used as the cations of ionic liquids where the anion was bis(trifluoromethanesulfonyl)imide. From the photonic crystals made with the block copolymers with molecular weights of 84k-69k and 57k-57k, the distinct colors were observed by swelling with the two ionic liquids.