ИСТИНА

Aniline template polymerization in the presence of Nafion® (DuPont, SigmaAldrich) and MF-4SK (Nafion® analogue from “Plastpolymer”, Russia) was carried out. Aniline polymerization in the presence of Nafion® and MF-4SK with molar ratio [aniline]/[Nafion® (MF-4SK)] 0.01-0.25 in 2-propanol/water mixture leads to the formation of soluble polyelectrolyte complex containing polyaniline. It was found that proton conductivity of composite membranes prepared from complexes reaches maximal value up to 0.2 S/cm and depends on composition of the initial reaction mixture as well as water uptake. Investigation of composite membrane with TEM showed that PANI influences on morphology of the composite membranes and leads to the structural change of ionogenic phase of MF-4SK. Based on PANI-Nafion® complexes a polymer memristor (resistor with a memory) was developed. PANI-Nafion® films were treated by LiOH during 7 days to substitute all protons in Nafion® with Li+ ions. These films, exhibiting both electron and Li+ conduction, show good cyclability behavior in acetonytrile solutions containing LiClO4 or LiCl with reversible processes taking place. It was found, that the electron conductivity of such films increases drastically at ca. 0.2 V, and remains high up to 1.5 V. When voltage is gradually lowered, conductivity decreases, exhibiting a large hysteresis of forward and backward conduction. If the device is switched off at some applied voltage, it keeps the last attained conductivity level during at least two hours, which is the manifestation of the memrisitive behavior. In contrast to the earlier explanations of memristive behavior in PANI, we anticipate that reversible electrochemically induced Red-Ox transition from leucoemeraldine into emeraldine salt and metastability of Red-Ox states in PANI is a ground for the memrisitve behavior.