The feed ratio of IILs/styrene, nitrogen content of copolymers and the molar ratio of IILs/styrene in copolymers are summarizedin Table 1. Sample A, B and C were polymerized by [VBI]Br with styrene, while Sample D, E and F were polymerized by [VMI]I with styrene. The Nitrogen only existed in the imidazolium cation groups, hence, the amount of imidazolium groups in the copolymers could be reflected by the nitrogen content and controlled by varying the feed ratio of IILs/styrene. It can be seen in Table 1 that the nitrogen content of copolymers decreased with the decreasing amount of ionic liquids. All the copolymers and OH form anion exchange membranes obtained in this work are soluble in alcohols and DMF, insoluble in ethyl ether, chloroform and tetrahydrofuran. Thus, the membranes could be prepared by solution
casting method mentioned in Section 2.4.