US 11,958,950 B2
Ion exchange membrane and method for producing dry ion exchange membrane
Shintaro Hayabe, Tokyo (JP); Osamu Homma, Tokyo (JP); Yasushi Yamaki, Tokyo (JP); Tatsuya Miyajima, Tokyo (JP); and Takuo Nishio, Tokyo (JP)
Assigned to AGC Inc., Tokyo (JP)
Filed by AGC Inc., Tokyo (JP)
Filed on Oct. 5, 2020, as Appl. No. 17/063,058.
Application 17/063,058 is a continuation of application No. PCT/JP2019/023744, filed on Jun. 14, 2019.
Claims priority of application No. 2018-114511 (JP), filed on Jun. 15, 2018; and application No. 2019-016153 (JP), filed on Jan. 31, 2019.
Prior Publication US 2021/0017347 A1, Jan. 21, 2021
Int. Cl. C08J 5/22 (2006.01); H01M 8/1039 (2016.01)
CPC C08J 5/2225 (2013.01) [H01M 8/1039 (2013.01); C08J 2327/12 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An ion exchange membrane containing a fluorinated polymer having a group represented by —SO3M (M is a hydrogen atom, an alkali metal or a quaternary ammonium cation) and, in the main chain, a group represented by —CF2—, wherein
in a case where by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light orthogonal to the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the peak area a2 of Raman shift 680 to 760 cm−1 to the peak area a1 of Raman shift 1,025 to 1,095 cm−1 is taken as A1, and
by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light parallel to the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the peak area b2 of Raman shift 680 to 760 cm−1 to the peak area b1 of Raman shift 1,025 to 1,095 cm−1 is taken as B1,
the ratio of said B1 to said A1 is at least 1.05,
wherein the ion exchange capacity of the fluorinated polymer is 1.25 to 2.05 meq/g dry resin, and
wherein the fluorinated polymer further has an ether bond site in a side chain, and
in a case where by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light orthogonal to the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the height h2 of the highest peak within a range of Raman shift 920 to 1,025 cm−1 to the height h1 of the highest peak within a range of Raman shift 1,025 to 1.095 cm−1 is taken as H1, and
by Raman spectroscopy, to a cross section in the thickness direction of the ion exchange membrane, polarized light parallel to the thickness direction is irradiated to obtain a spectrum chart, whereby the ratio of the height h4 of the highest peak within a range of Raman shift 920 to 1,025 cm−1 to the height h3 of the highest peak within a range of Raman shift 1,025 to 1,095 cm−1 is taken as H2,
the ratio of said H2 to said H1 is at least 1.15.