Uniaxially ordered conjugated polymer film prepared by electrochemical polymerization in a nematic liquid crystal with rubbing orientation method showing redox-driven tunable dichroism

Abstract

We demonstrate electrochemical polymerization of an aromatic conjugated monomer in a macroscopically aligned nematic liquid crystal. This method is a combination of employment of liquid crystal for electrolyte solution, rubbing technique, and electropolymerization. The resulting polymer film shows linear dichroism and anisotropy. Polarizing optical microscopy reveals that the polymer film is uniformly ordered on a macroscopic scale. These results indicate that the conjugated main chains grow along a director of the aligned nematic liquid crystal solvent. Recently, many researchers have studied conjugated polymers for their applications as organic

Anisotropic highly-conductive films of poly(3-methylthiophene) from epitaxial electropolymerization on oriented poly(vinylidene fluoride)

“…Goto et al demonstrated that electrochemical polymerization of 2,7-di(2-furyl)uorene in a macroscopically aligned nematic liquid crystal yields a uniaxially ordered polymer lm. 34 Electrochemical polymerization of bithiophene in a crystalline electrolyte has also been described. 35 Sakaguchi et al reported electrochemical epitaxial polymerization of 3-butoxy-4-methylthiophene on an iodinecovered gold electrode by applying voltage pulses.…”

“…A surfacepropagation mechanism gave single polythiophene wires which were observed by scanning tunnelling microscopy imaging. 36 These studies [34][35][36] did not report conductivity data for the aligned polymers. We are not aware of any previous studies on epitaxial electropolymerization induced by standard voltammetric cycling.…”

Synthesis of a pyrimidine-based new chiral inducer for construction of cholesteric liquid crystal electrolyte solution and its electrochemical polymerization, and stimulated emission like interference

“…They can be used as a reaction solvent because of good solvation properties [11,12]. In this case, the addition of non-LC compounds to LC materials destroys its liquid crystallinity, resulting in a transformation into isotropic liquid or solid, whereas the addition of a small amount of optically active molecules to non-chiroptically active nematic LC produces cholesteric liquid crystal (CLC) with helical aggregation structure [13,14].…”

Intramolecular charge transfer (ICT) of a chiroptically active conjugated polymer showing green colour

“…Therefore, electrochemical polymerisation in a liquid crystalline medium can control meso-or macroscopic structures of the resultant polymer lms. 35 One of the important advantages of this method is to generate chiroptically active polymer lms even from achiral monomers. In this research, we prepared an achiral monomer 4,7-bis(2,3-dihydrothieno[3,4-b]-1,4-dioxin-5-yl)-2,1,3-benzothiadiazole (EBE), consisting of an electron-donor-acceptor chemical structure, as shown in Scheme 1.…”