IP Library › Granted Patent US 12,567,598
Granted Patent B2
US 12,567,598 · App. 17/822,846 · Granted Mar 3, 2026

Proton exchange membranes for electrochemical reactions

Inventors: Chunqing Liu (Arlington Heights, IL); Chaoyi Ba (Schaumburg, IL); Nicole Karns (Des Plaines, IL); Xueliang Dong (Schaumburg, IL)
Assignee: UOP LLC
H01M8/1039C08G65/4006C08G65/48C08J5/2256C08J2371/10
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Quick Facts
Patent No.
US 12,567,598
App. No.
17/822,846
Granted
Mar 3, 2026
Kind
B2
Abstract

A proton-conducting polymer comprises a plurality of repeating units of formula (I) for electrochemical reactions. The polymer may be synthesized from a super acid catalyzed polyhydroxyalkylation reaction of monomers Ar 1 ′, Ar 2 ′, and X 1 ′ followed by a nucleophilic substitution reaction or a grafting reaction, and optionally an acidification reaction. Proton-exchange membranes and membrane electrode assemblies made from the polymer are also described.

Claims (126)

1 . A proton-conducting polymer comprising a plurality of repeating units of formula (I)

wherein one or more of Ar 1 , Ar 2 , and X 1 comprises an acid functional group, wherein the acid functional group comprises —SO 3 − Z + , —COO − Z + , or —PO 3 H − Z + , and wherein Z + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein Ar 1 is selected from the group consisting of:

and mixtures thereof;

wherein Ar 2 is selected from the group consisting of:

and mixtures thereof; and

wherein X 1 is selected from the group consisting of:

or a mixture of

one or more of:

wherein R 1 -R 36 are each independently hydrogen, a halogen, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 1 + , —COO − Z 1 + , or —PO 3 H − Z 1 + , and wherein Z 1 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 37 -R 39 are each independently hydrogen, a halogen, a nitro group, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or an alkoxy group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 2 + , —COO − Z 2 + , or —PO 3 H − Z 2 + , and wherein Z 2 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 40 is an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 3 + , —COO − Z 3 + , or —PO 3 H − Z 3 + , and wherein Z 3 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 50 , R 50 ′, R 50 ″, and R 50 ′″ are each independently hydrogen, a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group are substituted with an acid functional group or are substituted with a halogen and the acid functional group; wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof; with the proviso that one or more of R 50 and R 50 ′ is not hydrogen, or one or more of R 50 , R 50 ′, R 50 ″, and R 50 ′″ is not hydrogen;

wherein R 100 is independently a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group is substituted with an acid functional group or is substituted with a halogen and the acid functional group; wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein the halogen is F, Cl, Br, or I;

wherein A 1 , A 2 , and A 3 are each independently O, S, or N—R 200 and wherein R 200 is hydrogen, a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group is substituted with an acid functional group or is substituted with a halogen and the acid functional group;

wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein p is 1, 2, 3, or 4;

wherein q is 0, 1, 2, or 3;

wherein r, s, t, and o are independently 0, 1, 2, 3, 4, 5, or 6; and

wherein n is an integer from 0 to 5000;

wherein m is an integer from 5 to 5000; and

wherein a molar ratio of n/m is in a range of 0:1 to 20:1.

2 . The polymer of claim 1 wherein Ar 1 is selected from the group consisting of

and mixtures thereof,

wherein R 25 , R 26 , R 27 , and R 28 are each independently —H or —CH 3 ;

wherein p is 1 or 2; and

wherein q is 0 or 1.

3 . The polymer of claim 1 wherein Ar 2 is selected from the group consisting of

and mixtures thereof;

wherein R 29 -R 36 are each independently —CH 3 or —CF 3 ;

wherein R 50 , R 50 ′, R 50 ″, and R 50 ′″ are each independently hydrogen or —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof, with the proviso that one or more of R 50 and R 50 ′ is not hydrogen, or one or more of R 50 , R 50 ′, R 50 ″, and R 50 ′″ is not hydrogen; and

wherein r, s, t, and o are each independently 0 or 1.

4 . The polymer of claim 1 wherein X 1 is

wherein R 37 , R 38 , and R 39 are each independently —H, —CH 3 , —CH 2 CH 3 , —CH(CH 3 ) 2 , —C(CH 3 ) 3 , —CH 2 —C 6 H 5 , or —CH 2 —CH(CH 3 ) 2 ; and

wherein R 100 is —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof.

5 . The polymer of claim 1 wherein X 1 is a mixture of

wherein R 37 , R 38 , and R 39 are each independently —H, —CH 3 , —CH 2 CH 3 , —CH(CH 3 ) 2 , —C(CH 3 ) 3 , —CH 2 —C 6 H 5 , or —CH 2 —CH(CH 3 ) 2 ;

wherein R 40 is —CH 3 , —CH 2 CH 3 , or —C 6 H 5 ; and

wherein R 100 is —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof.

6 . The polymer of claim 1 wherein X 1 is a mixture of

wherein R 37 , R 38 , and R 39 are each independently —H, —CH 3 , —CH 2 CH 3 , —CH(CH 3 ) 2 , —C(CH 3 ) 3 , —CH 2 —C 6 H 5 , or —CH 2 —CH(CH 3 ) 2 ; and

wherein R 100 is —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof.

7 . The polymer of claim 1 wherein X 1 is a mixture of

wherein R 37 , R 38 , and R 39 are each independently —H, —CH 3 , —CH 2 CH 3 , —CH(CH 3 ) 2 , —C(CH 3 ) 3 , —CH 2 —C 6 H 5 , or —CH 2 —CH(CH 3 ) 2 ;

wherein R 40 is —CH 3 , —CH 2 CH 3 , or —C 6 H 5 ; and

wherein R 100 is —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof.

8 . The polymer of claim 1 wherein Ar 1 is selected from the group consisting of

and mixtures thereof.

9 . The polymer of claim 1 wherein Ar 2 is selected from the group consisting of:

and mixtures thereof;

wherein R 50 , R 50 ′, R 50 ″, and R 50 ′″ are each independently hydrogen or —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , Na + , K + , NH 4 + , or mixtures thereof, with the proviso that one or more of R 50 and R 50 ′ is not hydrogen, or one or more of R 50 , R 50 ′, R 50 ″, and R 50 ′″ is not hydrogen.

10 . The polymer of claim 1 wherein X 1 is

or a mixture of

and one or more of:

wherein R 100 is —(CH 2 ) 3 SO 3 − Z 4 + and wherein Z 4 + is H + , Na + , K + , NH 4 + , or mixtures thereof; and

wherein R 40 is —CH 3 , —CH 2 CH 3 , or —C 6 H 5 .

11 . The polymer of claim 1 wherein the polymer comprises the reaction product of:

reacting monomers Ar 1 ′, Ar 2 ′, and X 1 ′ via a polyhydroxyalkylation reaction in the presence of a super acid catalyst to synthesize a precursor polymer comprising a plurality of repeating units of formula (II) having phenolic hydroxyl functional groups:

wherein Ar 1 ′ is selected from the group consisting of:

and mixtures thereof;

wherein Ar 2 ′ is selected from the group consisting of:

and mixtures thereof;

wherein X 1 ′ is

or a mixture of

wherein Ar 1 is selected from the group consisting of:

and mixtures thereof;

wherein Ar 2 ″ is selected from the group consisting of:

and mixtures thereof;

wherein X 1 ″ is selected from the group consisting of:

or a mixture of

wherein R 1 -R 36 are each independently hydrogen, a halogen, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or both the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 1 + , —COO − Z 1 + , or —PO 3 H − Z 1 + , and wherein Z 1 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 37 -R 39 are each independently hydrogen, a halogen, a nitro group, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or an alkoxy group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or both the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 2 + , —COO − Z 2 + , or —PO 3 H − Z 2 + , and wherein Z 2 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 40 is an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or both the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 3 + , —COO − Z 3 + , or —PO 3 H − Z 3 + , and wherein Z 3 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein A 1 , A 2 , and A 3 are each independently O, S, or NH;

wherein p is 1, 2, 3, or 4;

wherein q is 0, 1, 2, or 3;

wherein r, s, t, and o are independently 0, 1, 2, 3, 4, 5, or 6; and

wherein n′ is an integer from 0 to 5000;

wherein m′ is an integer from 5 to 5000; and

wherein a molar ratio of n′/m′ is in a range of 0:1 to 20:1; and

reacting phenolic hydroxyl functional groups (—OH) on Ar 2 ″ and amide functional groups (—CONH—) on X 1 ″ on the precursor polymer with an electrophile via a nucleophilic substitution reaction or a grafting reaction, and optionally acidifying the polymer in an acid solution to form a proton-conducting polymer comprising a plurality of repeating units of formula (I)

wherein Ar 1 is selected from the group consisting of:

and mixtures thereof;

wherein Ar 2 is selected from the group consisting of:

and mixtures thereof, and

wherein X 1 is selected from the group consisting of:

or a mixture of

one or more of:

wherein R 1 -R 36 are each independently hydrogen, a halogen, an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 1 , —COO − Z 1 + , or —PO 3 H − Z 1 + , and wherein Z 1 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 37 -R 39 are each independently hydrogen, a halogen, a nitro group, an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or an alkoxy group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 2 + , —COO − Z 2 + , or —PO 3 H − Z 2 + , and wherein Z 2 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 40 is an alkyl group, an alkenyl group, an alkynyl group, or an aryl group, and wherein the alkyl group, the alkenyl group, the alkynyl group, or the aryl group is optionally substituted with a halogen, an acid functional group, or the halogen and the acid functional group, and wherein the acid functional group is —SO 3 − Z 3 + , —COO − Z 3 + , or —PO 3 H − Z 3 + , and wherein Z 3 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein R 50 , R 50 ′, R 50 ″, and R 50 ′″ are each independently hydrogen, a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group are substituted with an acid functional group or are substituted with a halogen and the acid functional group; wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof; with the proviso that one or more of R 50 and R 50 ′ is not hydrogen, or one or more of R 50 , R 50 ′, R 50 ″, and R 50 ′″ is not hydrogen;

wherein R 100 is independently a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group is substituted with an acid functional group or is substituted with a halogen and the acid functional group; wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein the halogen is F, Cl, Br, or I;

wherein A 1 , A 2 , and A 3 are each independently O, S, or N—R 200 and wherein R 200 is hydrogen, a substituted alkyl group, a substituted alkenyl group, a substituted alkynyl group, or a substituted aryl group, and wherein the substituted alkyl group, the substituted alkenyl group, the substituted alkynyl group, or the substituted aryl group is substituted with an acid functional group or is substituted with a halogen and the acid functional group;

wherein the acid functional group is —SO 3 − Z 4 + , —COO − Z 4 + , or —PO 3 H − Z 4 + , and wherein Z 4 + is H + , a metal cation, a quaternary ammonium cation, or mixtures thereof;

wherein p is 1, 2, 3, or 4;

wherein q is 0, 1, 2, or 3;

wherein r, s, t, and o are independently 0, 1, 2, 3, 4, 5, or 6; and

wherein n is an integer from 0 to 5000;

wherein m is an integer from 5 to 5000; and

wherein a molar ratio of n/m is in a range of 0:1 to 20:1.

12 . The polymer of claim 11 wherein Ar 1 ′ is selected from the group consisting of:

and mixtures thereof;

wherein R 25 , R 26 , R 27 , and R 28 are each independently —H or —CH 3 ;

wherein p is 1 or 2; and

wherein q is 0 or 1.

13 . The polymer of claim 11 wherein Ar 2 ′ is selected from the group consisting of:

and mixtures thereof;

wherein R 29 , R 30 , R 31 , R 32 , R 33 , and R 34 are each independently —CH 3 or —CF 3 ; and

wherein r, s, and t are independent 0 or 1.

14 . The polymer of claim 11 wherein X 1 ′ is

or a mixture of

wherein R 37 , R 38 , and R 39 are each independently —H, —CH 3 , —CH 2 CH 3 , —CH(CH 3 ) 2 , —C(CH 3 ) 3 , —CH 2 —C 6 H 5 , or —CH 2 —CH(CH 3 ) 2 ; and

wherein R 40 is —CH 3 , —CH 2 CH 3 , or —C 6 H 5 .

15 . A proton-exchange membrane comprising the polymer of claim 1 .

16 . The proton-exchange membrane of claim 15 wherein the proton-exchange membrane comprises a nonporous symmetric dense film membrane, an integrally-skinned asymmetric membrane, a reinforced composite membrane, or a thin film composite membrane.

17 . The proton-exchange membrane of claim 15 wherein the reinforced composite membrane or the thin film composite membrane comprises a porous substrate membrane impregnated or coated with the proton-conducting polymer.

18 . A membrane electrode assembly comprising:

a proton-exchange membrane comprising the polymer of claim 1 ;

an anode comprising an anode catalyst on a first surface of the proton-exchange membrane; and

a cathode comprising a cathode catalyst on a second surface of the proton-exchange membrane.

19 . The membrane electrode assembly of claim 18 further comprising:

an anode gas diffusion layer adjacent to the anode; and

a cathode gas diffusion layer adjacent to the cathode.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 29, 2022
From: LIU, CHUNQING; BA, CHAOYI; KARNS, NICOLE; DONG, XUELIANG
To: UOP LLC
Reel/Frame 060923/0518 →
Continuity (2)
Provisional Application 63262905 · Oct 22, 2021
Related Publication 20230125657A1 · Apr 27, 2023
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