US Patent 7888397 Poly(phenylene)-based anion exchange membrane

A poly(phenylene) compound of copolymers that can be prepared with either random or multiblock structures where a first polymer has a repeat unit with a structure of four sequentially connected phenyl rings with a total of 2 pendant phenyl groups and 4 pendant tolyl groups and the second polymer has a repeat unit with a structure of four sequentially connected phenyl rings with a total of 6 pendant phenyl groups. The second polymer has chemical groups attached to some of the pendant phenyl groups selected from CH3, CH2Br, and CH2N(CH3)3Br groups. When at least one group is CH2N(CH3)3Br, the material functions as an anion exchange membrane.