Porous nafion membrane and method for preparing the same

Patent metadata

Field	Value
Publication number	US-2016204459-A1
Application number	US-201514983439-A
Country	US
Kind code	A1
Filing date	Dec 29, 2015
Priority date	Jan 13, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

Provided are a method for preparing a Nafion membrane having a through-pore free monolithic porous structure throughout the bulk of the membrane through a one-step process very easily and a Nafion membrane having a through-pore free monolithic porous structure obtained from the method. The Nafion membrane having such a porous structure may have an increased surface area, and thus may improve the membrane/catalyst interfacial area and transport characteristics.

First claim

What is claimed is:

1 . A porous Nafion membrane, wherein a surface and a whole inner part of the Nafion membrane consists of a monolithic porous structure, and the monolithic porous structure is a through-pore free structure.

2 . The porous Nafion membrane according to claim 1 , wherein the porous Nafion membrane has a uniform monolithic porous structure free from giant pores, wherein open pores are distributed on both surfaces of the membrane and closed pores are distributed inside of the membrane.

3 . The porous Nafion membrane according to claim 1 , wherein all pores of the monolithic porous structure show a pore size deviation within +100% and −98% from average pore size of the monolithic porous structure.

4 . The porous Nafion membrane according to claim 1 , wherein the monolithic porous structure has the largest pore diameter (LPD) not exceeding twice of the 90% average pore diameter (APD 90 ).

5 . The porous Nafion membrane according to claim 1 , wherein the monolithic porous structure has pores less than 20% of which are connected and 80% or more of which are not connected but separated from each other.

6 . The porous Nafion membrane according to claim 1 , wherein the porous Nafion membrane maintains its membrane shape without any distortion of its membrane shape.

7 . The porous Nafion membrane according to claim 6 , wherein the porous Nafion membrane is an opaque white membrane.

8 . The porous Nafion membrane according to claim 1 , wherein the monolithic porous structure is obtained by a solvent evaporation process.

9 . The porous Nafion membrane according to claim 1 , wherein the porous Nafion membrane further comprises an additive that is an inorganic material, organometallic compound or a mixture thereof.

10 . The porous Nafion membrane according to claim 9 , wherein the additive is at least one selected from the group consisting of TiO 2 , SiO 2 , CeO 2 , Pt, Pd, copper (II) phthalocyanin tetrasulfonic acid and copper (II) phthalocyanin tetrasulfonic acid tetrasodium salt.

11 . The porous Nafion membrane according to claim 1 , wherein the porous Nafion membrane further comprises an ion conductive polymer membrane formed thereon.

12 . The porous Nafion membrane according to claim 11 , wherein the ion conductive polymer membrane is a second Nafion membrane having an ion exchange capacity different from the ion exchange capacity of Nafion in the porous Nafion membrane; sulfonated polysulfone membrane; PBI membrane; or an anion conductive polymer membrane.

13 . The porous Nafion membrane according to claim 1 , wherein the porous Nafion membrane is for use in a fuel cell, sensor, electrolytic cell, redox flow batteries, gas separator or a humidifier.

Assignees

• Korea Inst Sci & Tech

Inventors

• Henkensmeier Dirk
• Joseph Dickson
• Jang Jong Hyun
• Kim Jin Young
• Kim Hyoung-Juhn
• Han Jonghee
• Nam Suk Woo
• Yoon Sung Pil

Classifications

• H01M2300/0082

  Organic polymers · CPC title

• H01M8/1067

  characterised by their physical properties, e.g. porosity, ionic conductivity or thickness · CPC title

• C08J2300/12

  Polymers characterised by physical features, e.g. anisotropy, viscosity or electrical conductivity · CPC title

• H01M8/1023 Primary

  having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes · CPC title

• H01M8/1081

  starting from solutions, dispersions or slurries exclusively of polymers · CPC title