Synthesis and properties of polymer brushes bearing ionic liquid moieties

Poly(1-ethyl 3-(2-methacryloyloxy ethyl) imidazolium chloride) (PEMEIm-Cl) brushes were grafted onto Au surface via surface initiated atom transfer radical polymerization (ATRP). The swelling/collapsed behavior of the brushes was characterized by AFM in different electrolyte solutions. These 15 nm ultrathin polyelectrolyte brushes can be used to modulate the interfacial resistance via conformational changes triggered by external electrolytes and solvent. The interfacial resistance was characterized using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) using [Fe(CN)6]3−/4− as the redox probe. The effects of electrolytes, the concentration and type of electrolytes and temperature are investigated in more detail.