Imidazoles and imidazolium cations with exceptional alkaline stability

A polymer comprising a plurality of imidazolium-containing repeating units represented by a structural formula selected from

• wherein:
• R2′ is selected from C1-C6 alkyl or R2;
• R2 is phenyl substituted with 0 to 3 substituents R6 each independently selected from C1-C3 alkyl;
• R3′ is selected from hydrogen, methyl, or R3;
• R3 is selected from C2-C16 hydrocarbyl;
• R4 and R5 each is independently selected from C1-C16 hydrocarbyl, or, taken together, R4 and R5, together with the carbon atoms to which they are attached, form a ring selected from benzene, cyclooctene or norbornene;
• X− is a counterion;
• wavy lines indicate points of attachment to adjacent repeating units of the polymer;
• and
• Z is C1-C8 hydrocarbyl, wherein one carbon atom of the C1-C8 hydrocarbyl may optionally be replaced by O.