HYDROPHILIC, COMPOSITE, MICROPOROUS MEMBRANE AND ITS PRODUCTION METHOD

• US 20090234032A1
• Filed: 12/15/2006
• Published: 09/17/2009
• Est. Priority Date: 12/15/2005
• Status: Abandoned Application

• Current Assignee: Tonen Chemical Corp. (ENEOS Holdings, Inc.)
• Original Assignee: Tonen Chemical Corp. (ENEOS Holdings, Inc.)
• Inventors: Kimishima, Kotaro
• Application Number:
  US12/097,462
• Publication Number:
  US 20090234032A1
• Time in Patent Office: Days
• US Class Current: 521/27
• CPC Class Codes: B01D 2323/36 Introduction of specific chemical groups
• CPC Class Codes: B01D 2323/38 Graft polymerization
• CPC Class Codes: B01D 2325/18 Membrane materials having mixed charged functional groups
• CPC Class Codes: B01D 2325/36 Hydrophilic membranes
• CPC Class Codes: B01D 67/009 with wave-energy, particle-radiation or plasma
• CPC Class Codes: B01D 67/0093 Chemical modification
• CPC Class Codes: B01D 67/00931 by introduction of specific groups after membrane formation, e.g. by grafting
• CPC Class Codes: B01D 69/125 In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
• CPC Class Codes: B01D 69/127 using electrical discharge or plasma-polymerisation
• CPC Class Codes: B01J 43/00 Amphoteric ion-exchange, i.e. using ion-exchangers having cationic and anionic groups; Use of material as amphoteric ion-exchangers; Treatment of material for improving their amphoteric ion-exchange properties ion-exchange chromatography processes B01D15/36
• CPC Class Codes: B01J 47/12 characterised by the use of ion-exchange material in the form of ribbons, filaments, fibres or sheets, e.g. membranes electrodialysis or electro-osmosis B01D61/42
• CPC Class Codes: C02F 1/44 by dialysis, osmosis or reverse osmosis general membrane separation processes B01D61/00, membrane modules B01D63/00, electrodialysis C02F1/4693, combination of membrane modules and bioreactors C02F3/1268
• CPC Class Codes: C02F 1/441 by reverse osmosis
• CPC Class Codes: C02F 1/444 by ultrafiltration or microfiltration
• CPC Class Codes: H01M 50/414 Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: H01M 50/489 Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: H01M 50/491 Porosity
• CPC Class Codes: H01M 8/1072 by chemical reactions, e.g. insitu polymerisation or insitu crosslinking
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

A hydrophilic, composite, microporous membrane having an anion exchange group and a cation exchange group on the outer surface or pore surface of a microporous, thermoplastic resin membrane substrate has excellent water permeability, mechanical strength, fine-particles-removing properties, anion-removing properties and cation-removing properties.

Claims

1. A hydrophilic, composite, microporous membrane having an anion exchange group and a cation exchange group on the outer surface or pore surface of a microporous, thermoplastic resin membrane substrate.

2. The hydrophilic, composite, microporous membrane according to claim 1, wherein the anion exchange group is any one of primary to quaternary amino groups and heterocyclic amine groups.

3. The hydrophilic, composite, microporous membrane according to claim 1, wherein the cation exchange group is a sulfonic acid group or a carboxyl group.

4. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of graft-polymerizing a microporous, thermoplastic resin membrane substrate with an unsaturated glycidyl compound, and adding an anion exchange group and a cation exchange group to an epoxy group in the resultant polymer.

5. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of graft-polymerizing a microporous, thermoplastic resin membrane substrate with an anion-exchange-group-containing unsaturated monomer and a cation-exchange-group-containing unsaturated monomer.

6. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of (i) graft-polymerizing a microporous, thermoplastic resin membrane substrate with a unsaturated glycidyl compound, bonding an anion exchange group to an epoxy group in the resultant polymer, and then graft-polymerizing the anion-exchange-group-containing substrate with a cation-exchange-group-containing unsaturated monomer, or (ii) graft-polymerizing a microporous, thermoplastic resin membrane substrate with an unsaturated glycidyl compound and a cation-exchange-group-containing unsaturated monomer, and then bonding an anion exchange group to an epoxy group in the resultant polymer.

7. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of (i) graft-polymerizing a microporous, thermoplastic resin membrane substrate with an unsaturated glycidyl compound and an anion-exchange-group-containing unsaturated monomer, and then bonding a cation exchange group to an epoxy group in the resultant polymer, (ii) graft-polymerizing a microporous, thermoplastic resin membrane substrate with an unsaturated glycidyl compound, bonding a cation exchange group to an epoxy group in the resultant polymer, and then graft-polymerizing the resultant cation-exchange-group-containing substrate with an anion-exchange-group-containing unsaturated monomer.

8. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of graft-polymerizing a microporous, thermoplastic resin membrane substrate with an unsaturated glycidyl compound, bonding an anion exchange group to an epoxy group in the resultant polymer, and then subjecting the resultant anion-exchange-group-containing substrate to a plasma gas treatment or a corona discharge treatment to form a carboxyl group.

9. A method for producing the hydrophilic, composite, microporous membrane recited in claim 1, comprising the steps of graft-polymerizing a microporous, thermoplastic resin membrane substrate with an anion-exchange-group-containing unsaturated monomer, and then subjecting the resultant anion-exchange-group-containing substrate to a plasma gas treatment or a corona discharge treatment to form a carboxyl group.