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CN-116157195-B - Composite membrane

CN116157195BCN 116157195 BCN116157195 BCN 116157195BCN-116157195-B

Abstract

A composite membrane comprising a) a first layer comprising a first porous support and a first ionic polymer present in pores of the first porous support, b) a second layer comprising a second porous support and a second ionic polymer present in pores of the second porous support, c) a third layer comprising a third porous support, a third ionic polymer and a fourth ionic polymer, wherein the third ionic polymer is present in pores of the third porous support, wherein (i) one of the first ionic polymer and the second ionic polymer is a cationic polymer and the other is an anionic polymer, (ii) the third layer c) is interposed between the first layer a) and the second layer b), (iii) the third ionic polymer comprises a network of pores and the fourth ionic polymer is present within pores of the third ionic polymer, and (iv) one of the third ionic polymer and the fourth ionic polymer is a cationic polymer and the other is an anionic polymer.

Inventors

  • R. M. Ripken
  • E. Huerta Martinez
  • NARITA TAKESHI
  • M. C.G.M. Merrick
  • Yazko Hessin

Assignees

  • 富士胶片制造欧洲有限公司
  • 富士胶片株式会社

Dates

Publication Date
20260508
Application Date
20210902
Priority Date
20200903

Claims (20)

  1. 1. A composite membrane, comprising: a) A first layer comprising a first porous support and a first ionomer present in the pores of the first porous support; b) A second layer comprising a second porous support and a second ionomer present in the pores of the second porous support; c) A third layer comprising a third porous support, a third ionomer, and a fourth ionomer, wherein the third ionomer is present in the pores of the third porous support; Wherein: (i) One of the first ionic polymer and the second ionic polymer is a cationic polymer and the other is an anionic polymer; (ii) The third layer is interposed between the first layer and the second layer; (iii) The third ionic polymer comprising a network of pores and the fourth ionic polymer being present within the pores of the third ionic polymer, and (Iv) One of the third ionic polymer and the fourth ionic polymer is a cationic polymer and the other is an anionic polymer.
  2. 2. The composite membrane of claim 1 wherein a third ionic polymer is obtained by a process comprising phase separating the third ionic polymer from a composition used to prepare the third ionic polymer.
  3. 3. The composite membrane of claim 2 wherein the phase separation is polymerization-induced phase separation.
  4. 4. A composite membrane as claimed in any one of claims 1 to 3, wherein the network of pores comprises the first ionic polymer and the second ionic polymer such that the first ionic polymer acts as a fourth ionic polymer to partially fill the pores of the third ionic polymer and the second ionic polymer fills the remaining pores.
  5. 5. A composite membrane as claimed in any one of claims 1 to 3 wherein the third ionomer has the same charge as the second ionomer.
  6. 6. A composite membrane as claimed in any one of claims 1 to 3, wherein the third ionic polymer and the fourth ionic polymer present in the third layer form a co-continuous network, wherein the third ionic polymer and the fourth ionic polymer are discrete and unevenly mixed with each other.
  7. 7. A composite film according to any one of claims 1 to 3, wherein the first, second and third layers each independently have an average thickness of 10 to 200 μm.
  8. 8. A composite film according to any one of claims 1 to 3 comprising a first interface between the first and third layers and a second interface between the third and second layers, and both the first and second interfaces being uninterrupted, there being no gap and/or space between the first and third layers and no gap and/or space between the third and second layers.
  9. 9. A composite membrane as claimed in any one of claims 1 to 3 comprising a third interface between the third ionic polymer and the fourth ionic polymer, the interface being uninterrupted without any gaps and/or spaces between the third ionic polymer and the fourth ionic polymer.
  10. 10. A composite film according to any one of claims 1 to 3, wherein the first ionic polymer is obtained by a process comprising curing a first curable composition comprising: (a1) 0 to 60% by weight of a curable compound having one ethylenically unsaturated group and an ionic group; (b1) 1 to 88 weight percent of a curable compound comprising at least two ethylenically unsaturated groups and an ionic group; (c1) 0 to 10% by weight of a free radical initiator, and (D1) 0 to 55% by weight of a solvent.
  11. 11. The composite film of claim 10, wherein the second ionic polymer is obtained by a process comprising curing a second curable composition comprising: (a2) 0 to 60 weight percent of a curable compound having one ethylenically unsaturated group and an ionic group of opposite charge to the curable compound present in the first curable composition; (b2) 1 to 88 weight percent of a curable compound comprising at least two ethylenically unsaturated groups and an ionic group; (c2) 0 to 10% by weight of a free radical initiator, and (D2) 0 to 55% by weight of a solvent.
  12. 12. A composite film according to any one of claims 1 to 3, wherein the third ionic polymer is obtained by a process comprising curing a third curable composition comprising: (a3) 0 to 60% by weight of a curable compound having one ethylenically unsaturated group and an ionic group; (b3) 1 to 70 weight percent of a curable compound comprising at least two ethylenically unsaturated groups and an ionic group; (c3) 0 to 10% by weight of a free radical initiator, and (D3) 20 to 98% by weight of a solvent.
  13. 13. The composite film of claim 12, wherein the fourth ionic polymer is obtained by a process comprising curing a fourth curable composition comprising: (a4) 0 to 60 weight percent of a curable compound having one ethylenically unsaturated group and an ionic group of opposite charge to the curable compound present in the third curable composition; (b4) 1 to 88 weight percent of a curable compound comprising at least two ethylenically unsaturated groups and an ionic group; (c4) 0 to 10% by weight of a free radical initiator, and (D4) 0 to 55% by weight of a solvent.
  14. 14. A composite membrane according to any one of claims 1 to 3 which is a composite bipolar membrane.
  15. 15. A composite membrane according to any one of claims 1 to 3 wherein the volume ratio of the third ionic polymer to the fourth ionic polymer is from 0.1 to 0.9.
  16. 16. A method of making a composite membrane comprising the steps of: I. providing a first porous support, a second porous support, and a third porous support; Providing a first curable composition comprising a curable compound, a second curable composition comprising a curable compound having an opposite charge to the curable compound present in the first curable composition, a third curable composition comprising a curable compound, and a fourth curable composition comprising a curable compound having an opposite charge to the curable compound present in the third curable composition; impregnating the third porous support with the third curable composition; curing the third curable composition present in the third porous support to form a base layer comprising the third porous support and a third ionic polymer comprising a network of pores; impregnating the pore network of the third ionic polymer with the fourth curable composition; contacting the first curable composition with a first side of the base layer; contacting the second curable composition with a second side of the base layer, and Curing the first curable composition, the second curable composition, and the fourth curable composition in any order or simultaneously to form a first ionic polymer, a second ionic polymer, and a fourth ionic polymer, respectively; Wherein: (a) When the first curable composition is cured, the first curable composition includes the first porous support; (b) The second curable composition includes the second porous support when the second curable composition is cured; (c) One of the first curable composition and the second curable composition comprises a curable compound having an ethylenically unsaturated group and an anionic group, and the other comprises a curable compound having an ethylenically unsaturated group and a cationic group, and (D) One of the third curable composition and the fourth curable composition comprises a curable compound having an ethylenically unsaturated group and an anionic group, and the other comprises a curable compound having an ethylenically unsaturated group and a cationic group.
  17. 17. The method of claim 16, wherein the first curable composition comprises the first porous carrier when the first curable composition is applied to the first side of the base layer.
  18. 18. The method of claim 16, wherein the first porous carrier is applied to the first curable composition after the first curable composition has been applied to the first side of the base layer.
  19. 19. The method of any one of claims 16 to 18, wherein the second curable composition comprises the second porous carrier when the second curable composition is applied to the second side of the base layer.
  20. 20. The method of any one of claims 16 to 18, wherein the second porous carrier is applied to the second curable composition after the second curable composition has been applied to the second side of the base layer.

Description

Composite membrane The present invention relates to composite membranes and methods of making and using the same. Ion exchange membranes are used in electrodialysis, reverse electrodialysis, electrolysis, diffusion dialysis and many other processes. Typically, the transport of ions through the membrane occurs under the influence of a driving force, such as an ion concentration gradient or a potential gradient. Ion exchange membranes are generally classified as either cation exchange membranes or anion exchange membranes according to their primary charge. The cation exchange membrane comprises negatively charged groups that allow cations to pass through but repel anions, while the anion exchange membrane comprises positively charged groups that allow anions to pass through but repel cations. Bipolar ion exchange membranes have both a cationic layer and an anionic layer. Some ion exchange membranes comprise a porous support that provides mechanical strength. Such membranes are commonly referred to as "composite membranes" due to the presence of an ionically charged polymer that distinguishes between oppositely charged ions and a porous support that provides mechanical strength. For example, a composite membrane is known from US4,253,900, which describes a bipolar membrane comprising a single bead layer of ion exchange resin. The articles of WO2017/205458 and mccure on pages 35-44 of ECS Transactions,2015 69 (18) describe a bipolar membrane comprising a tie layer of interpenetrating polymer nanofibers or microfibers of an anion exchange polymer and a cation exchange polymer. Other examples of composite membranes are described in e.g. EP3604404, wherein one layer comprises ion exchange resin powder, and US4673454, which discloses the use of ion exchange resins in an interface layer. It is desirable to provide composite membranes with improved properties such as high permeation selectivity, low electrical resistance, good mechanical strength, low swelling under aqueous conditions, stability at extreme pH. Ideally, such films can be produced quickly, efficiently, and inexpensively. According to a first aspect of the present invention, there is provided a composite membrane comprising: a) A first layer comprising a first porous support and a first ionomer present in the pores of the first porous support; b) A second layer comprising a second porous support and a second ionomer present in the pores of the second porous support; c) A third layer comprising a third porous support, a third ionomer, and a fourth ionomer, wherein the third ionomer is present in the pores of the third porous support; Wherein: (i) One of the first ionic polymer and the second ionic polymer is a cationic polymer and the other is an anionic polymer; (ii) The third layer c) is interposed between the first layer a) and the second layer b); (iii) The third ionic polymer comprising a network of pores and the fourth ionic polymer being present within the pores of the third ionic polymer, and (Iv) One of the third ionic polymer and the fourth ionic polymer is a cationic polymer and the other is an anionic polymer. In this specification (including the claims hereof), the verb "to comprise" and its conjugations is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. In addition, the indefinite article "a" or "an" does not exclude the possibility that more than one element is present, unless the context clearly requires that there be one and only one element. Thus, the indefinite article "a" or "an" generally means "at least one". In addition, in the present specification, the third ionic polymer comprising a network of pores is generally abbreviated as "third ionic polymer". Preferably, the porous support is nonionic. In a preferred embodiment, the third ionic polymer may be obtained by phase separating the third ionic polymer from the composition used to prepare the third ionic polymer. In this way, a third ionic polymer comprising a network of pores may be obtained and the pores may be used to receive a fourth ionic polymer (or a curable composition for preparing a fourth ionic polymer) in order to produce a third layer c). In one embodiment, the curable composition used to prepare the fourth ionic polymer is the same as the curable composition used to prepare the first ionic polymer. In this way, a composite film in which the first ionic polymer is the same as the fourth ionic polymer can be obtained. Preferably, the third ionic polymer comprises a porous first polymer domain (polymeric domain) comprising ionic groups and a network of pores. Preferably, the fourth ionic polymer comprises a second polymer domain comprising ionic groups of opposite charge to the ionic groups of the first polymer domain. In this embodiment, the second polymer domain is located in the pores of the first polymer domain (i.e., in the pores of the third ionic polymer). In a particularl