Protic Oligosilsesquioxane Dicationic Ionic Liquids with Two Types of Ionic Sites in Organic Frame

Abstract

A method of synthesis of oligomeric siloxane protic ionic liquids capable of condensation reactions has been developed as starting compounds in the obtaining proton exchange membranes for fuel cells. Their organic frame is characterized by a combination of amine centers of different basicity (aliphatic and imidazole types) neutralized with ethanesulfonic acid and secondary hydroxyl groups. A change in the degree of neutralization of the amine centers significantly affects the structure of the compounds and the mechanism of proton migration. The conductivity of the obtained compounds reaches 9.8·10^–4 S/cm at 100°C in the absence of moisture.