Thermally stable hydrocarbon-based anion exchange membrane and ionomers

Patent metadata

Field	Value
Publication number	US-11969723-B2
Application number	US-202217901985-A
Country	US
Kind code	B2
Filing date	Sep 2, 2022
Priority date	Mar 20, 2020
Publication date	Apr 30, 2024
Grant date	Apr 30, 2024

Abstract

An anion exchange membrane is composed of a copolymer of 1,1-diphenylethylene and one or more styrene monomers, such as 4-tert-butylstyrene. The copolymer includes a backbone substituted with a plurality of ionic groups coupled to phenyl groups on the backbone via hydrocarbyl tethers between about 1 and about 7 carbons in length. High-temperature conditions enabled by these copolymers enhance conductivity performance, making them particularly suitable for use in anion exchange membranes in fuel cells, electrolyzers employing hydrogen, ion separations, etc. The properties of the membranes can be tuned via the degree of functionalization of the phenyl groups and selection of the functional groups, such as quaternary ammonium groups. Several processes can be used to incorporate the desired ionic functional groups into the polymers, such as chloromethylation, radical bromination, Friedel-Crafts acylation and alkylation, sulfonation followed by amination, or combinations thereof.

First claim

What is claimed is:

1. A method of making an ion exchange membrane material, comprising:
providing a reaction medium including diphenylalkylene and styrene;
copolymerizing a polymer backbone from the diphenylalkylene and styrene; and
reacting the polymer backbone to functionalize phenyl groups on the polymer backbone with a plurality of ionic functional groups.

2. The method according to claim 1 , wherein reacting the polymer backbone to functionalize phenyl groups on the polymer backbone with a plurality of ionic functional groups includes chloromethylation, radical bromination, Friedel-Crafts acylation and alkylation, sulfonation followed by amination, or combinations thereof.

3. The method according to claim 1 , wherein reacting the polymer backbone to functionalize phenyl groups on the polymer backbone with a plurality of ionic functional groups includes:
reacting the polymer backbone with one or more alkylated substrates,
wherein the alkylated substrate includes a hydrocarbyl group and at least one ionic group.

4. The method according to claim 1 , wherein the diphenylalkylene includes 1,1-diphenylethylene.

5. The method according to claim 1 , wherein the styrene is substituted styrene, unsubstituted styrene, or combinations thereof.

6. The method according to claim 5 , wherein ion exchange membrane material includes a polymer according to Formula II:

wherein R 2 is H, an alkylated substrate, or combinations thereof; R 3 is H, a tert-butyl group, an alkylated substrate, or combinations thereof; and m is 1 or more,
wherein the alkylated substrate includes a hydrocarbyl group and at least one ionic group.

7. The method according to claim 6 , wherein the alkylated substrate includes one or more quaternary ammonium groups, one or more multication hydrocarbyl groups, one or more halide groups, or combinations thereof.

8. The method according to claim 7 , wherein the alkylated substrate includes Formula III:

wherein each R 4 includes H or CH 3 ; n=1 to about 20; and X includes one or more hydroxides, halides, or combinations thereof.

9. The method according to claim 6 , wherein the percentage of R 2 and R 3 that are an alkylated substrate is between about 10% and about 100%.

Assignees

• Rensselaer Polytech Inst

Inventors

• Lee Sangwoo
• Bae Chulsung
• Trant Carrie Lynn

Classifications

• B01J41/14 Primary

  obtained by reactions only involving unsaturated carbon-to-carbon bonds · CPC title

• C08F212/08

  Styrene · CPC title

• C08F212/32

  containing two or more rings · CPC title

• C08J5/2231

  based on macromolecular compounds obtained by reactions involving unsaturated carbon-to-carbon bonds · CPC title

• C08J2325/08

  Copolymers of styrene (C08J2329/08, C08J2335/06, C08J2355/02 take precedence) · CPC title