Anhydrous proton conductor based on heterocycle attached to a polymer backbone

Abstract

The invention relates to proton-conducting polymers, including tetrazole-containing polymers. Proton-conducting membranes useful for fuel cell applications are formed from mixtures of a polymer with one or more non-aqueous proton sources. In representative examples of the present invention, tetrazole groups are attached to a polymer backbone such as polyphosphazene, the tetrazole groups interacting with the proton source.

1 - 20 . (canceled) 
   
   
       21 . An anhydrous proton-conducting membrane comprising:
 a polymer having a single polymer backbone; and   a heterocyclic group attached to the single polymer backbone.   
   
   
       22 . The anhydrous proton-conducting membrane of  claim 21 , wherein the heterocyclic group is a tetrazole group directly bound to the single polymer backbone by a chemical bond. 
   
   
       23 . The anhydrous proton-conducting membrane of  claim 22 , wherein the tetrazole group is linked to the polymer backbone through a linking group. 
   
   
       24 . The anhydrous proton-conducting of  claim 21 , wherein:
 the single polymer backbone is selected from the group consisting of: polyphosphazene, polyether ketone, polystyrene, polyphenylene, poly(trifluorostyrene) polysulfone, polyimide, polyazole, silicon-containing polymers, and polyimidazole.   
   
   
       25 . The anhydrous proton-conducting polymer of  claim 23  wherein the linking group is selected from the group consisting of: alkyl, alkoxy, aryl and alkenyl groups. 
   
   
       26 . The anhydrous proton-conducting polymer of  claim 21  wherein the heterocyclic group is a tetrazole containing substituent attached to the single polymer backbone. 
   
   
       27 . The anhydrous proton-conducting polymer of  claim 26  wherein the tetrazole containing substituent is attached to the single polymer backbone through substitution of a halogen in the single polymer backbone by a nucleophilic group. 
   
   
       28 . The anhydrous proton-conducting polymer of  claim 27  wherein the nucleophilic group is selected from the group consisting of: an alkali salt of phenol, aliphatic alcohol, aliphatic amine, aromatic amine, and nitrile. 
   
   
       29 . The anhydrous proton-conducting membrane of  claim 21 , wherein the proton-conducting membrane is a component of a membrane electrode assembly (MEA), the MEA comprising:
 a first electrode,   a second electrode, and   the proton-conducting membrane located between the first electrode and the second electrode.   
   
   
       30 . The anhydrous proton-conducting membrane of  claim 29 , wherein the MEA is part of a fuel cell.