The copolymers for preparing OH form anion exchange
membranes based on two types of imidazolium ionic liquid
monomers were synthesized via free radical polymerization, as
mentioned in Section 2.3. The synthetic routes are shown in
Scheme 2 and Scheme 3. Because of the strong water affinity of
imidazolium ionic liquids, styrene was introduced to the polymer
backbone to adjust the hydrophilic-lipophilic balance of the
membranes. The properties of the copolymers could be tuned by
varying the monomer ratios in the reactants.