Anion exchange polymers and anion exchange membranes incorporating same
An anion exchange membrane is made by mixing 2 trifluoroMethyl Ketone [nominal] (1.12 g, 4.53 mmol), 1 Biphenyl (0.70 g, 4.53 mmol), methylene chloride (3.0 mL), trifluoromethanesulfonic acid (TFSA) (3.0 mL) to produce a pre-polymer. The pre-polymer is then functionalized to produce an anion exchange polymer. The pre-polymer may be functionalized with trimethylamine in solution with water. The pre-polymer may be imbibed into a porous scaffold material, such as expanded polytetrafluoroethylene to produce a composite anion exchange membrane.
1. A method of making a composite anion exchange membrane comprising the steps of:
a) mixing the following components:
i) 2 trifluoromethyl ketone;
ii) 1 biphenyl;
iii) methylene chloride; and
iv) trifluoromethanesulfonic acid,
for a mixing time and temperature to produce a pre-polymer,
b) providing a porous scaffold;
c) dissolving the pre-polymer in an imbibing solution comprising methanol to produce a solution of the pre-polymer; and
d) combining the pre-polymer solution and the porous scaffold by imbibing and subsequently functionalizing the pre-polymer; and
e) drying the functionalized pre-polymer solution to produce a composite anion exchange membrane.
2. The method of making a composite anion exchange membrane of claim 1 , wherein the step of functionalizing comprises exposing the pre-polymer to trimethylamine in a solution with water.
3. The method of making a composite anion exchange membrane of claim 1 , wherein the porous scaffold is an expanded polytetrafluoroethylene membrane.