Polymers obtained from monomers allowing a sequential polymerization, and their use for preparing ionic conductors

Abstract

The present invention concerns polymers obtained by anionic initiation and bearing functions that can be activated by cationic initiations that are not reactive in the presence of anionic polymerization initiators. The presence of such cationic initiation functions allow an efficient cross-linking of the polymer after moulding, particularly in the form of a thin film. It is thus possible to obtain polymers with well-defined properties in terms of molecular weight and cross-linking density. The polymers of the present invention are capable of dissolving ionic compounds inducing a conductivity for the preparation of solid electrolytes.

What is claimed is:  
     
         1 . Cross-linkable polymer obtained by anionic polymerization initiation followed by cationic cross-linking, the polymer being of general formula:  
       (A) n Q(Y) p    
       wherein 
 Q represents a bond, —CO—, —SO 2 —, or an organic radical of n+p valence non reactive towards reagents initiating anionic or cationic polymerization, of the type alkyl, alkylaryl, arylalkyl optionally comprising oxa or aza substituents, and comprising from 1 to 30 carbon atoms;  
 A represents a radical reactive in anionic polymerization;  
 Y represents a radical reactive in cationic polymerization and non-reactive toward agents initiating anionic polymerization;  
 n varies between 1 and 3; and  
 p varies between 1 and 6.  
 
     
     
         2 . Polymer according to  claim 1  wherein A comprises  
       
         
           
           
               
               
           
         
       
       Y comprises  
       
         
           
           
               
               
           
         
         Z represents O or CH 2 ;  
         R represents H, an alkyl or oxa-alkyl radical of from 1 to 12 carbon atoms, CN or  
         CH 2 COOR 1  wherein R 1  is 14 or an alkyl or oxa-alkyl radical of 1 to 12 carbon atoms;  
         R′ represents H or an alkyl radical of 1 to 12 carbon atoms; and  
         r varies between 1 and 6.  
       
     
     
         3 . Polymer obtained by anionic initiation characterized in that it comprises a co-monomer according to  claim 1  wherein only the A group of the compound (A) n Q(Y) p  are incorporated in the polymer.  
     
     
         4 . Polymer according to  claim 3  wherein the polymerization of the A group and the co-monomers is performed sequentially to form di-block or tri-block type polymers.  
     
     
         5 . Polymer according to  claim 3  wherein molding of the polymer is done after polymerization of the A groups.  
     
     
         6 . Polymer according to  claim 3  wherein the cross-linking, hardening of the polymer or interpenetrated network formation is done by polymerization of the Y groups.  
     
     
         7 . Polymer according to  claim 5  wherein the polymerization of the Y groups is carried out in the presence of other monomers, oligomers or polymers bearing functions that can be activated by a reagent initiating cationic polymerization, radicalar polymerization, or both.  
     
     
         8 . Polymer according to  claim 5  further comprising an additive in the form of powder, fibers or both, optionally treated, so that its surface is compatible with and adheres to the polymer or polymer mixtures.  
     
     
         9 . Polymer according to  claim 5  wherein the polymerization of the Y groups and any optional additives in the form of monomers, oligomers or polymers is carried out thermally, through actinic radiation, or both, optionally in the presence of initiators or sensitizers.  
     
     
         10 . Polymer according to  claim 3  further comprising at least one plasticizer.  
     
     
         11 . Polymer according to  claim 8  wherein the additive is organic or inorganic, and optionally possesses ionic conduction properties, intrinsic electronic properties, optical properties, a high dielectric constant, piezoelectric properties, or combinations thereof.  
     
     
         12 . Polymer according to  claim 3  characterized in that it is a polyepoxide and A comprises  
       
         
           
           
               
               
           
         
       
     
     
         13 . Polymer according to  claim 12  characterized in that it is an ethylene oxide based copolymer comprising at least one monomer (A) n Q(Y) p  as defined above.  
     
     
         14 . Polymer according to  claim 12  wherein the monomer comprises:  
       
         
           
           
               
               
           
         
       
       wherein 
 R 5  is a divalent alkyl or oxa-alkyl of from 0 to 12 carbon atoms; and  
 R′ is as defined above.  
 
     
     
         15 . Polymer according to  claim 13  characterized in that at least one co-monomer is used in addition to ethylene oxide when A is  
       
         
           
           
               
               
           
         
       
     
     
         16 . Polymer according to  claim 15  wherein the co-monomer comprises propylene oxide, butylene oxide, monoepoxide of dienes of from 4 to 10 carbon atoms, glycidol ethers with methyl, ethyl and allyl groups.  
     
     
         17 . Polymer according to  claim 3  based on styrene units and wherein A comprises  
       
         
           
           
               
               
           
         
       
     
     
         18 . Polymer according to  claim 17  characterized in that it is a copolymer of α-alkyl(oligoethoxy)-ω-vinylbenzyle of general formula:  
       
         
           
           
               
               
           
         
       
       wherein 
 p varies between 2 and 60;  
 R 6  is an a monovalent alkyl of from 1 to 18 carbon atoms, or a monovalent aryl of from 5 to 18 carbon atoms;  
 Q is (CH 2 ) q , —CO— or —SO 2 —; and  
 q varies between 0 and 4.  
 
     
     
         19 . Polymer according to  claim 17  wherein the monomer comprises  
       
         
           
           
               
               
           
         
       
       wherein R′ and Q are as defined above, and R 7  is R 5 .  
     
     
         20 . Polymer according to  claim 17  wherein at least one other monomer is used in addition to α-alkyl(oligoethoxy)-ω-vinylbenzyl when A comprises  
       
         
           
           
               
               
           
         
       
     
     
         21 . Polymer according to  claim 3  characterized in that it is acrylate-based and that A comprises  
       
         
           
           
               
               
           
         
       
       wherein R is as defined above.  
     
     
         22 . Polymer according to  claim 21  characterized in that it is a copolymer of α-alkyl(oligoethoxy)ethyle acrylate, methacrylate or itaconate, of general formula:  
       
         
           
           
               
               
           
         
       
       wherein 
 p varies between 2 and 60; and  
 R represents H, an alkyl or oxa-alkyl radical of from 1 to 12 carbon atoms, CN or  
 CH 2 COOR 1  wherein R 1  is H or an alkyl or oxa-alkyl radical of 1 to 12 carbon atoms.  
 R 6  is a monovalent alkyl of from 1 to 18 carbon atoms or a monovalent aryl of from 5 to 18 carbon atoms.  
 
     
     
         23 . Polymer according to  claim 21  wherein the monomer comprises  
       
         
           
           
               
               
           
         
       
       wherein R 7 , R and R′ are as defined above.  
     
     
         24 . Polymer according to  claim 21  characterized in that at least one other monomer of the organic or metallic acrylate type is used in addition to the α-alkyl(oligoethoxy)ethyle acrylate, methacrylate or itaconate.  
     
     
         25 . An ionic conduction material comprising at least one polymer according to  claim 3  and at least one salt M n+ X n   − , M n+  being an inorganic, organic, or organometallic cation of charge n, and X −  being a monovalent anion, and wherein two or more anions X −  can be linked together with covalent chains or chains belonging to a polymer chain.  
     
     
         26 . A material according to  claim 25  wherein at least a fraction of the cations comprise lithium ion.  
     
     
         27 . A material according to  claim 25  wherein at least one fraction of the anions X −  comprises ClO 4   − , BF 4   − , PF 6   − , AsF 6   − , SbF 4   − , R f SO 3   − , (R x SO 2 NSO 2 R′ x ) − , (R x SO 2 C(SO 2 R′ x )R x ″) − , anions derived from cyclopentadiene and its aza analogs bearing electro-attracting groups, anions derived from pyrimidine-trione or 1,3-dioxane-4,5-dione bearing electro-attracting groups, and malonitrile derivatives, wherein R x  and R x ′ are the same or different and at least one has electronegative atoms, and wherein R x ″ is R x , R x ′SO 2 — or R x ′SO 2   − .  
     
     
         28 . A material according to  claim 27  wherein at least a fraction of the anions comprises ClO 4   − , BF 4   − , PF 6   − , CF 3 SO 3   − , (FSO 2 ) 2 N − , (CF 3 SO 2 ) 2 N − , (C 2 F 5 SO 2 ) 2 N − , [(CF 3 SO 2 ) 2 CH] − , [CF 3 SO 2 )C(CN) 2 ] − , [(CF 3 SO 2 ) 3 C] − , (CF 3 SO 2 )NSO 2 N(R 9 ) 2 ) −  wherein R 9  represents an alkyl of from 1 to 30 carbon atoms, anions derived from 4,5-dicyano-1,2,3-triazole, 3-5-bistrifluoromethyl-1,2,4-triazole, or tricyanomethane.  
     
     
         29 . A material according to  claim 25  wherein at least one fraction of the anions is borne by the chain of the polymer or is part of the chain of a different polymer, in admixture or forming an interpenetrated network with the polymer.  
     
     
         30 . A material according to  claim 25  wherein at least a fraction of the anions has A or Y groups independently or simultaneously, or viinylic bonds are incorporated in the polymer chain during the cationic or anionic polymerization step, or through the cationic+radicalar combined process.  
     
     
         31 . A material according to  claim 11  wherein the end of the chains obtained after the anionic polymerization react during activation of the Y groups to cause the cross-linking or co-cross-linking, thus leading to acetal-type stable bonds.  
     
     
         32 . A material according to  claim 31  wherein the polymer weight before cross-linking is comprises between 2×10 3  and 60×10 3  g/mol.  
     
     
         33 . An electrochemical cell wherein the electrolyte comprises at least in part a material according to  claim 25 .  
     
     
         34 . An electrical energy storage system of the primary or secondary generator type, or super-capacity, comprising at least one negative electrode and at least one positive electrode comprising at least in part a material according to  claim 25 .  
     
     
         35 . A system according to  claim 34  wherein the ions participating to the electrode reactions are lithium ions.  
     
     
         36 . A system according to  claim 34  wherein the negative electrode comprises metallic lithium or an alloy thereof, optionally in the form of a nanometric dispersion in lithium oxide, double nitrides of lithium and a transition metal, low potential oxides of general formula Li 1+y Ti 2−c/4 O 4 , wherein x≧0 and y≦1, MoO 2 , WO 2 , carbon and carbonated products obtained from organic material pyrolysis, lithium-aluminum or lithium-silicon alloys.  
     
     
         37 . A system according to  claim 34  wherein the positive electrode further comprises another material comprising vanadium oxides Li y VO x  wherein (2x−5≦y≦2x−3; 2.15≦x≦2.5), Li y N 1−x−z Co x Al z O 2  wherein 0≦x+y≦1 et 0≦y≦1, manganese spinels Li y Mn 2−x M x O 4  wherein M is Li, Cr, Al, V, Ni, 0≦x≦0,5 et 0≦y≦2, organic polydisulfides, polyquinones like rhodizonates, FeS, FeS 2 , iron sulphate, phosphates and phosphosilicates of iron and lithium of the olivine or Nasicon-type structure, or substitution products of iron with manganese, used alone or in combination.  
     
     
         38 . A system according to  claim 34  wherein the material further comprises a plasticizer comprising a polar liquid selected from the group consisting of acyclic and cyclic carbonates, γ-butyrolactone, carboxylic acid esters, tetraalkylsulfamides, dialkylated ethers of mono, di, tri and tetraetylene glycols and oligomers of a weight lower than 2000 g/mol and mixtures thereof.  
     
     
         39 . System for light modulation comprising two supports wherein at least one is transparent, coated with a tin oxide based conductor or doped indium oxide conductor, and a layer of an electrochromic material and a counter-electrode characterized in that the electrolyte is a material according to  claim 25 .  
     
     
         40 . System according to  claim 39  further comprising a coloring agent susceptible of changing of coloration depending on its degree of oxidation.