Organic-inorganic membranes

Abstract

The invention relates to organic/inorganic hybrid polymer blends and hybrid polymer blend membranes that are composed of: one polymer acid halide containing SO 2 X, POX 2 or COX groups (X═F, Cl, Br, I); one elemental or metallic oxide or hydroxide, obtained by the hydrolysis and/or the sol/gel reaction of an elemental and/or organometallic compound during the membrane forming process and/or by subsequently treating the membrane in aqueous acidic, alkaline or neutral electrolytes. The invention further relates to hybrid blends and hybrid blend membranes containing polymers that carry SO 3 H, PO 3 H 2 and/or COOH groups, obtained by aqueous, alkaline or acidic hydrolysis of the polymer acid halides contained in the polymer blend or the polymer blend membrane. The invention also relates to methods for producing the inventive hybrid blends and hybrid blend membranes.

1 . Membranes containing at least one polymeric acid halide, characterized in that before, during or after the membrane formation process salts, metal oxides or metal hydroxides or their organic precursors are incorporated into the membrane.  
     
     
         2 . Membranes according to  claim 1  characterized in that the polymeric acid halide is an aryl main chain polymer and carries SO 2 X, POX 2 , COX or BX 2  groups (X═F, Cl, Br, I) and is chosen from the group of polyether sulfones, polysulfones, polyphenyl sulfones, polyether ether sulfones, polyether ketones, polyether ether ketones, polyphenylene ethers, polydiphenylphenylene ethers, polyphenylene sulfides or is a copolymer, that contains at least one of these components.  
     
     
         3 . Membranes according to one or more of  claims 1  to  2 , characterized in that they contain a salt, element or metal oxide or metal hydroxide, which has been obtained by hydrolysis and/or sol/gel reaction before, during or after membrane formation and is chosen from the following precursors: 
 metal/element alkoxides/esters of Ti, Zr, Sn, Si, B, Al  
 metal acetylacetonates, e.g. Ti(acac) 4 , Zr(acac) 4    
 mixed compounds of metal/elemental alkoxides and  
 metal acetylacetonates, e.g. Ti(acac) 2 (OiPr) 2  etc.  
 organic amino compounds of Ti, Zr, Sn, Si, B, Al  
 
     
     
         4 . Membranes according to  claim 3 , characterized in that the SO 2 X, POX 2 , COX or BX 2  groups (X═F, Cl, Br, I) of the membrane polymer are changed by a hydrolysis reaction which happens after membrane formation to SO 3 Y, PO 3 Y 2 , COOY or B(OY) 2  groups (Y═H, a univalent or bivalent metal cation, ammonium ion, imidazolium ion, pyrazolium ion, pyridinium ion).  
     
     
         5 . Membranes according to one or more of  claims 1  to  4  characterized in that they are additionally covalently cross-linked.  
     
     
         6 . Membranes according to one or more of  claims 1  to  5  characterized in that the membranes are posttreated with phosphoric acid to generate in the membrane matrix from the metal oxides and/or metal hydroxides and/or metal oxides hydroxides the metal phosphates or element phosphates or metal hydrogenphosphates or element hydrogenphosphates or metal dihydrogenphosphates or element dihydrogenphosphates, which contribute to proton conductivity.  
     
     
         7 . Process for the preparation of membranes according to one or more of  claims 1  to  6  characterized in that the following components are mixed in a dipolar-aprotic solvent such as N-methylpyrrolidinone (NWP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO) or sulfolane or in an ether solvent such as tetrahydrofuran, dioxan, glyme, diglyme, triglyme etc.: a polymeric acid halide with SO 2 X, POX 2 , COX or BX 2  groups (X═F, Cl, Br, I), and at least metal-organic or element organic compounds according to the compounds of  claim 3 .  
     
     
         8 . Process according to  claim 7  characterized in that the polymer solution of  claim 6  is cast into thin films on a support (glass-plate or metal plate, tissue, wovens or non-wovens, fleece, porous (polymer)membrane), the solvent is evaporated at temperature of 80 to 150° C. at normal pressure or under vacuum and the formed thin film is posttreated as follows, whereby the order of posttreatment steps can vary and also optionally the steps (1) and/or (2) and/or (3) can be omitted: 
 (1) in water at T=50 to 100° C.  
 (2) in 1 to 100% mineral acid (hydrohalic acid, sulfuric acid, phosphoric acid) at T=50 to 100° C.  
 (3) in 1 to 50% aqueous base (e.g. ammonia solution, amine solution, sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, calcium hydroxide solution, barium hydroxide solution) or in an anhydrous liquid amine or mixture of different amines.  
 (4) in water at T=50 to 100° C.  
 
     
     
         9 . Use of membranes according to  claim 1  to produce energy by an electrochemical way.  
     
     
         10 . Use of membranes according to  claim 1  to produce energy or substances by a photochemical way.  
     
     
         11 . Use of membranes according to  claim 1  as component in membrane fuel cells (H 2  or direct methanol fuel cells) at temperatures of from 0 to 180° C.  
     
     
         12 . Use of membranes according to  claim 1  electrochemical cells.  
     
     
         13 . Use of membranes according to  claim 1  in secondary batteries.  
     
     
         14 . Use of membranes according to  claim 1  in electrolysis cells.  
     
     
         15 . Use of membranes according to  claim 1  in membrane separation processes such as gas separation, pervaporation, perstraction, reverse osmosis, electrodialysis and diffusion dialysis.