CA2283668C - Cross-linked sulphonated polymers and method for preparing same - Google Patents

Abstract

The invention concerns cross-linked sulphonated polymers, optionally perfluorinated, and the method for preparing them. When they are moulded in the form of membranes, said polymers are useful in electrochemical cells, in a chlorine-sodium electrolysis process, as separator in en electrochemical preparation of organic and inorganic compounds, as separator between an aqueous phase and an organic phase, or as catalyst for Diels-Alder additions, Friedel-Craft reactions, aldol condensations, cationic polymerisation, esterification, and acetal formation.

Description

TITLE

Crosslinked sulfonated polymers and process for their preparation FIELD OF THE INVENTION

The present invention relates to ion exchange resins of the type cationic, especially in membrane form, preferably partially or totally fluorinated, their applications, particularly in applications electrochemicals such as fuel cells, chlor-alkali processes, electrodialysis, ozone production, sensors, as well as any other application related to the dissociation of anionic centers attached to the membrane, such as catalysis heterogeneous in organic chemistry.

PRIOR ART

Because of their chemical inertness, ion exchange membranes partially or totally fluorinated are usually chosen from processes chlorine-soda or fuel cells that consume hydrogen or methanol. Of such membranes are commercially available under such names as than NafionTM, FlemionTM, DowTM. Other similar membranes are proposed by Ballard Inc. in WO 97/25369, which discloses copolymers of tetrafluoroethylene and perfluorovinyl ethers or trifluorovinylstyrene. The monomers active at from which these copolymers are obtained carry chemical functions which are precursors of ionic groups of sulfonate or carboxylate type. Examples of these precursors are:

2 -F2C = CF-0 CF2-CF-CF2-CF2-SOIF
X in F2C = CF-CF2 IFO (CF2 CO2CH3 X n or F2C = CF ~ (S02F
wherein X is F, Cl or CF3;

- n is 0 to 10 inclusive; and - p is 1 or 2;

The aromatic polymers of the polyimide or sulfonated polyether sulfone type have also been considered, for example O S02X fn or O
NONO
=
OO S02X n Once obtained, the copolymer containing the aforementioned precursors is molded, for example in the form of sheets, then converted into ionic form by hydrolysis for give species of sulfonate or carboxylate type. The cation associated with anion

3 -sulfonate and carboxylate includes the proton, the cation of an alkali metal (Li +, Na +, K); the cation of an alkaline earth metal (Mg +, Cal +, Bat +); the cation of a metal of transition (Zn`, Cu`); A13 +; Fei '; the cation of a rare earth (Sc3 + Y3 + La3 +) ; an organic cation of "onium" type, such as oxonium, ammonium, pyridinium, guanidinium, amidinium, sulfonium, phosphonium, these organic cations being optionally substituted by a or more organic radicals; an organometallic cation such as metallocenium arene-metallocenium, alkylsilyl, alkylgennanyl or alkyltin.

Such membranes, however, have several significant disadvantages.
A) Although the copolymers forming the membrane are insoluble in their shape ionic, the membrane does not have good dimensional stability and swells way significant in water or polar solvents. These copolymers form micelles reversed only when heated at high temperature in a mixture specific water-alcohol, which, after evaporation, makes it possible to produce a film. However, this movie regenerated in solid form does not have good mechanical properties.

B) Tetrafluoroethylene (TFE) is a product whose handling is very risky because its polymerization is carried out under pressure and may cause controlled especially in the presence of oxygen. Because of the point difference boiling between the two monomers forming the copolymer and their polarity difference, it is difficult to obtain a statistical copolymer corresponding to the addition rate of each monomer.

C) The ionic groups in high concentration on the chain would have tendency to cause the solubilization of the copolymer. In order to prevent this phenomenon, concentration ionic groupings is kept at a low rate by adding a significant fraction

-4-molar monomers of TFE and / or increasing the length of the chains secondary (n> 1), with the result that the concentration of ion groups exchangeable is less than 1 milliequivalent per gram. As a result, the conductivity is relatively weak and very sensitive to the water content in the membrane, particularly when the latter is acidified for applications in a battery to combustible.

D) The penetration of methanol and oxygen through the membrane is high, since the perfluorocarbon portion of the polymer allows easy diffusion of cash molecules, which will chemically react with the opposite electrode and cause a loss Faradaic efficiency, mainly in fuel cells methanol.

Non-fluorinated systems such as sulfonated polyimides or polyethers sulphonated sulphones have the same disadvantages since it is necessary to compromise between the charge density, hence the conductivity, and the solubility or excessive swelling.
SUMMARY OF THE INVENTION

The present invention relates to a sulfonated polymer comprising a fraction or all of the crosslinked sulfonyl groups, and in which at least a fraction crosslinking bonds carry an ionic charge, the bonds of cross-linking are type:

P-S02-Y (M +) - SO2-P ' P-SO 2 (M +) Y-SO2- (Q-SO2), Y- (M +) SO2-P ' in which - P and P 'are identical or different and are part of a polymer chain;

-5-Y is N or CR where R is H, CN, F, SO 2 R 3, substituted or unsubstituted substituted; C6_20 substituted or unsubstituted aryl or substituted or unsubstituted C2-C20 alkylene, the substituent being one or more halogens, and wherein the chain comprises a or some substituents selected from F, SO2R where R is defined above, aza, oxa, thia and s dioxathia;

R3 is F, C1-C4 alkyl substituted or unsubstituted; C6-20 substituted aryl or unsubstituted or C2-2o substituted or unsubstituted alkylene, the substituent being one or more halogens;

M + is H +; a metal cation selected from an alkali metal, an alkali metal earth; a transition metal and a rare earth; an organometallic cation or a cation organic onium;

Q is a divalent CI-20 alkyl, CI-20 oxaalkyl, C1-20 alkyl, C1-Thiaalkyl, C6-2o aryl or C6.2o alkylaryl, each is optionally substituted with a or some halogen, and in which the chain is substituted with one or more substituents oxa, aza or thia; and r is 0 or 1, the divalent radical and the sulfonated polymer are partially or totally fluorinated.

In a preferred embodiment, M + comprises H +, a metal cation, a organometallic cation or an onium organic cation, the latter being optionally substituted with one or more organic radicals chosen from:

proton, alkyl, alkenyl, oxaalkyl and oxaalkenyl radicals, azaalkyl, azaalkenyl, thiaalkyl, thiaalkenyl, dialkylazo, silalkyl optionally hydrolysable or silaalkenyl optionally hydrolysable, the radicals are linear, branched or cyclic and having from 1 to 18 carbon atoms;

-6-aliphatic cyclic or heterocyclic radicals of 4 to 26 atoms carbon optionally having at least one side chain having one or more selected heteroatoms from nitrogen, oxygen and sulfur; and aryls, arylalkyls, alkylaryls or alkenylaryls with 5 to 26 carbon atoms carbon having s optionally one or more heteroatoms in the aromatic ring or in a substituent.
The metal preferably comprises an alkali metal, an alkali metal, earthy, a rare earth or a transition metal; the organometallic cation includes a metallocenium, an arene-metallocenium, an alkylsilyl, an alkylgermanyl or a alkyltin, and the organic onium cation is selected from ammonium NR "+, a amidinium R "C (NHR") 2+, a guanidinium C (NHR ") 3+, a pyridinium C5R" N +, a imidazolium C3R "N2 +, a C2R triazolium" N3 +, an imidazolinium C3R "N2 +, a sulfonium SR "+, a phosphonium PR" +, an iodonium IR "+, a carbonium (C6R") 3C +, in which R "is defined as an organic radical as defined above, and when The organic cation has at least two radicals R "other than H, these radicals can form together an aromatic cycle or not, possibly including the center carrying the cationic charge.

In another preferred aspect the divalent radical Q and the sulfonated polymer 20 are partially or totally fluorinated.

The present invention further comprises a method for crosslinking sulfonyl groups of a sulfonated polymer in which at least one fraction of the

-7-crosslinking bonds carry an ionic charge, the process comprising implementation contact of the polymer with a crosslinking agent allowing the reaction between sulfonyl groups from adjacent polymer chains to form said crosslinking bonds, the crosslinking bonds are:

P-SO 2 -Y "(M) -SO 2 -P; Or P-S02 (M +) Y-SO2- (Q-SO 2) rY (M +) SO2-P ' in which - P and P 'are identical or different and are part of a polymer chain;

Y is N or CR where R is H, CN, F, SO 2 R 3, substituted or unsubstituted C 1 -C 20 alkyl substituted;
C6_20 substituted or unsubstituted aryl or C2_20 substituted or unsubstituted alkylene substituted, the substituent being one or more halogens, and wherein the chain comprises a or some substituents F, SO2R where R is defined previously, aza, oxa, thia and dioxathia;

- R3 is F, C1_20 alkyl substituted or unsubstituted; C6_20 substituted aryl or unsubstituted or C2_20 substituted or unsubstituted alkylene, the substituent being one or more halogens;

- M + is H +; a metal cation selected from an alkali metal, an alkali metal earthy, a transition metal and a rare earth; an organometallic cation or a cation organic onium;

Q is a divalent C1-20 alkyl, C1-20 oxaalkyl or C1-20 azaalkyl radical, C1-20 thiaalkyl, C 6-20 aryl or C 6-20 alkylaryl, each is optionally substituted with a or some Halogen, and in which the chain is substituted with one or more substituents oxa, aza or thia; and r is 0 or 1, the divalent radical and the sulfonated polymer are partially or totally fluorinated.

- 7a -The preferred crosslinking agents are of formula:
(M +) A2Y;

(M +) AY-SO2Y-A (M +);
(M +) AY-SO2QY-A (M +) in which Y, Q and M are as previously defined, and A comprises Si (R ') 3, Ge (R ') 3 or Sn (R') 3 wherein R 'is C, _ alkyl. Preferably, A is a group tri (C1-18) alkyl silyl.

DETAILED DESCRIPTION OF THE INVENTION

It is well known that perfluorinated polymers usually can not to be cross-linked by conventional techniques used for non-fluorinated polymers because of the easy removal of the fluoride ion and the bulk steric chains perfluorinated. However, the present invention describes a new technique general for create crosslinks, ie, links, between sulfonyl groups attached to adjacent polymer chains, including those having a perfluorinated backbone, example, those derived from the monomer (I) and its copolymers:

F2C = CF-O CF2-i F-CF2-CF2-SO2F
X n I

Advantageously, the crosslinking can be carried out while the polymer

-8-is in the form of a non-ionic polymer precursor, but after having been molded under the desired shape. This results in a much stronger material mechanically.
The present invention also relates to the molding of the crosslinked polymer under form membranes or hollow fibers (hereinafter "membranes") for use in a battery fuel, electrolyzer in water, a chlor-alkali process, electrosynthesis, the water treatment and ozone production. The use of polymers reticulated as catalysts of certain chemical reactions, thanks to the strong dissociation of the ionic groups introduced by the crosslinking technique and the insolubility of the polymer chain, is also part of the invention.

The present invention relates to an electrochemical cell in which a membrane comprising a crosslinked polymer as obtained according to the process described previously is used as solid electrolyte.

The present invention also extends to an electrochemical cell such that defined above comprising a fuel cell, an electrolyser with water, a chlor-alkali battery, an electrochemical battery with salt or acid coating, or a stack producing ozone.

The present invention also extends to an electrochemical cell defined above, characterized in that the cell forms an element of stack at fuel in which M + is a hydrated proton and the positive electrode contains a hydrogen reducing catalyst.

- 8a-Creating stable crosslinks is done through a reaction enter two -SO2Y groups from adjacent polymer chains. The reaction is initiated by a crosslinking agent, and allows the formation of derivatives according to the formulas following:

H SO2L + LSO2 A2Y- (M +) l -11 ~ V ~ i M +
+ 2 LA
or

-9 SO2L + LSO2 A (M +) - YSO2 (QSO2) ry (M +) A
SO2- YYS02 (QS02) ry - SO2 M + M +
+2 LA
in which r, M, Y and Q are as defined above;

- A is M, Si (R ') 3, Ge (R') 3 or Sn (R ') 3 where R' is C1-18 alkyl; and L is a leaving group bound to sulfonyl groups before carrying out the s crosslinking chosen from a halogen (F, Cl, Br), a heterocycle electrophilic N-imidazolyl and N-triazolyl, R2SO3 in which RZ is an organic radical optionally halogen as defined above.

The cation M + may itself be solvated or complexed to increase its solubility and / or its reactivity. For example, if M is a proton, this last can be complexed with a tertiary base with a strong nucleophilic character, such as triethylamine, dimethylaminopyridine, 1,4-diazabicyclo [2.2.2] octane, or form tert-butyl radical which readily separates into proton and CH2 = C (CH3) 3. If M
is an ion metal, the latter can be solvated by dialkyl ethers of ethylene glycols, or Methylated oligoethylenediamines.

In one variant, the crosslinking agent A2Y- (M +) can be formed in situ in presence of a strong base, for example an organometallic or a dialkyl amine metal such as lithium diisopropylamide reacts on labile protons related to the radical Y as follows:

HN [Si (CH 3) 3] 2 + C 4 H 9 Li b C 4 O 1 O + LiN [Si (CH 3) 3] 2;

-10-CH2 [Si (CH3) 3] SO2CF3 + 2CH3MgC1Li 2CH4 + (MgCl) 2C [Si (CH3) 3] SO2CF3 Preferred organometallic crosslinking agents include organophosphorus lithium, organo-magnesium or organo-aluminum, which also serve as a source of carbon when Y = CR, and metal amides and nitride as a source nitrogen when Y = N.

An advantage of the present invention is that the crosslinking agents create negatively charged species that are attached to groups sulphonyls polymers and used as a bridge between adjacent polymer chains.
It is well known as sulfonylimide groups and di- or trisulfonylméthane are strong electrolytes in most media, and in this sense, the reaction of cross-linking, in addition to improving the mechanical properties, has no effect harmful to the conductivity. In fact, the latter is often increased.

The following compounds are examples of ionogenic crosslinking agents preferential, ie, generator of ionic groups, when L is on the chain polymer: Li3N; C3A14i [(CH3) 3Si] 2NLi; [(CH3) 3Si] 2NNa; [(CH3) 3Si] 2nk; NH3 + 3 DABCO; CF3SO2C [(CH3) 3Si] [Li (TMEDA)] 2i (CH3) 3CNH2 + 3 TEA; NH2SO2NH2 + 4 TEA; [[(CH 3) 3 Si] (Li) N] 2 SO 2 1 [(TMEDA) (Mg) N] 2 SO 2; CH 3 Li; (CH3) 3A1; NH2Li;
NHZNa; NHZK; [[Si (CH3) 3] (Li) NSOZ] 2CF2; [Li [Si (CH3) 3] NSOZCF2] 2CF2;
[(Li) Si (CH3) 3NSO2CF2]; and [Li [Si (CH 3) 3] NSO 2 CF 2 CF 2 O 2 O, wherein TEA
triethylamine; TMEDA: N, N, N'N'tetramethylethylenediamine; DABCO = 1.4-diazabicyclo [2,2,2] - octane.

-11-Alternatively, the crosslinking reaction can take place when the group Y is already on the precursor of the polymer, for example in the case a substituted amide. In this case, the general scheme is as follows:

OO

M + M +
LS02 (QS02) rL
oio SO2 YS02 (QS02) rY-SO2 M + M +
+ 2 LA

The following compounds are examples of ionogenic crosslinking agents preferential when L is on the reagent: SO2C12 + 3 DABCO; S02 (imidazole) 2;
[FSO2CF2] 2 + 3 TEA; (ClSO2CF2) CF2 + 3 DABCO and (FSO2CF2CF1) 20 + 3 DABCO.

The crosslinking reaction may involve all the groups sulfonyls, or only a fraction of these. Crosslinking reagents can be added or used according to different techniques well known to the person of career.
Advantageously, the polymer is molded in the desired form before the crosslinking, by example in the form of membrane or hollow fiber, and the material is immersed or covered with a solution of the crosslinking agent in one or more inert solvents promoting the coupling reaction. The solvents are selected from the group comprising: aromatic hydrocarbons, hydrocarbons and ethers aliphatic partially or totally halogenated, THF, the alkyl ethers of mono-, di- and tetraethylene glycols, tertiary alkylamides chosen from DMF, 2-N-methylpyrrolidone, tetramethylurea and its cyclic analogues, N-alkylimidazoles, - lla-tetraalkylsulfamides, and mixtures thereof. Preferred solvents are polyhalocarbons, tetrahydrofuran (THF), glymes, alkylamides tertiary dimethylformamide, N-methylpyrrolidone, tetramethylurea and its similar cyclic N-alkylimidazoles and tetraalkylsulfamides. The degree of crosslinking desired can be controlled by different factors, such as time immersion in the

-12-solvent containing the crosslinking agent, the temperature of the solvent, the concentration of crosslinking agent in the solvent, or a combination of these factors.
Of preferably, these parameters are adjusted to produce the properties desired in a relatively short time ranging from a few seconds to a dozen hours, and s temperatures are chosen as compatible with the usual solvents, from -10 C to 250 C. By way of comparison, the hydrolysis of a Nafion membrane takes more 24 hours for the usual thicknesses.

Alternatively, a latex of the polymer to be molded is preferably mixed into the presence of fluids that are not solvents, such as hydrocarbons ordinary or fluorinated, with the crosslinking agent in solid form and the mixture is pressed or calendered hot. This technique is advantageously applied to thin membranes, and provide high productivity even though it is possible that the membrane resulting is less homogeneous. Reinforcing agents such as agents of Fillers, organic or inorganic, such as powders, fibers or filaments woven fabrics or not, can be added to the polymers before the reaction of cross-linking for strengthen the structure. Similarly, agents allowing to create a porosity ("porophores") may be incorporated when it is desirable to increase surfaces of exchange with external fluids (case of catalysis).

If only a fraction of the links bridging the chains polymers are required, the remaining SO2Y groups can be hydrolyzed conventional sulfonate form by alkaline hydrolysis.
Alternatively, the uncrosslinked polymer is molded and contacted with the crosslinking agent and an agent - 12a -non-crosslinking ionogen to form end groups -SO3- (M +), or - [SO2YSO2R] - (M +), R is an organic radical as defined above. R
is preferably halogenated, more preferably perhalogenated. In a mode of production preferentially, the sulfonate group -SO3-M + and the non-groupings

-13-crosslinked -SO2NSO2RFM + or -SO2C (R) SO2RF M + wherein RF comprises a radical preferably halogenated organic, particularly fluorinated, may be obtained in the same conditions as during crosslinking reactions from non ionogens crosslinking agents such as M + [(CH3) 3SiO], M + [(CH3) 3SiNSO2RF] or M + [(CH3) 3SiC (R) SO2RF]

s or any other agent capable of introducing groups - NSO2RF or C (R) SO2RF in substitution of Y. M + is as defined above and RF is a radical alkyl, oxaalkyl, azaalkyl or substantially perfluorinated thiaalkyl of 1 to 12 atoms of carbon.
It may be advantageous to treat the membrane sequentially or simultaneously with the crosslinking agent, and then with the non-crosslinking ionic agent.

Alternatively, the crosslinking agent and the non-crosslink ionizing agent are mixed and dissolved in a solvent in predetermined concentrations, so that they react simultaneously.

The crosslinked polymer obtained according to the process of the present invention can to be 15 readily separated from the by-products of the reaction, which are either volatile, as the (CH 3) 3 SiF or (CH 3) 3 SiCl. Alternatively, the cross-linked polymer can be washed help a suitable solvent such as water or an organic solvent in which it is insoluble.
In addition, conventional techniques well known to those skilled in the art, like ion exchange or electrophoresis, can be used to change the Cation M + obtained in the crosslinking reaction and / or from the agent ionogen no crosslinking by the desired cation for the final application.

The present invention extends to a polymer as defined above derived from at least one of the following monomers:

- 13a-CF2 = CF F2-CF tn C

X FX F

FO CF2-i F O-CF2-CF2-SO2L
not CF2 = CF- (~) j- SO2L
CF2 = CF-SO2L.

CZ2 = CZ-E - (~) r- SO2L
CZ2 = CZ-E
S02L CZ2 = CZ-E
e-S02L
E-CZ = CZ2 The or o ~ - o0-S4 S02L n.
in which X is F, CI or CF3;

- n varies between 0 and 10 inclusively;
- E is absent, O, S or S02;

Z is H or F; and - L is a labile group.

- 13b -The present invention also relates to the use of a crosslinked polymer such previously defined in a chlor-alkali electrolysis process, such as separator in an electrochemical preparation of organic and inorganic compounds, as separator between an aqueous phase and an organic phase, or as a catalyst for the Diels-Alder additions, Friedel-Craft reactions, aldol condensations, the cationic polymerization, esterifications, and acetal formation.

The following examples are provided to illustrate the invention, and must in no time be considered as limiting the scope.

Example 1 WO 99/38897

14 PCT / CA99 / 00078 -

15 g of polyethersulfone in powder form are sulphonated with 11 g of acid chlorosulfonic acid in 75 ml of 1,2-dichloroethane. The concentration of groups sulfonic acid reaches 0.47 SO3H units per aromatic ring. Groupings SO3H are transformed into SOZCI groups by the action of an excess of chlorinated chloride dimethylaminium in DMF. The polymer in powder form is filtered and then wash with anhydrous acetonitrile and dried under vacuum. Under anhydrous atmosphere, the polymer in chlorosulfonated form is shaped into film by pressing and calendering at 150 C.
A 50 micron thick film is cut into 4 cm squares and immersed in a solution of 0.6 g of the lithiated derivative of hexamethyl disilazane Li [N (Si (CH 3) 3) 2] in 50 1 ml of dimethylethyleneurea (DMEU). The polymer is treated in these conditions during 1 hour at 110 C under dry argon atmosphere. The membrane is removed from the middle reaction mixture, rinsed with THF and treated with an excess of trimethylsilanoate lithium (1 g) in 50 ml of 1,2-dimethoxyethane under argon for 24 hours at 25 ° C.
membrane is rinsed several times with distilled water and the metal ions are exchanged by protons in a Soxhlet-type extractor with an acid solution hydrochloric acid azeotropic concentration in water (ie, 20.2% by weight). The membrane thus obtained has a conductivity greater than 10-3 Scm 'at 25 ° C and 95% relative humidity.
24% of sulfonyl groups are engaged in the formation of imidure bridges and the membrane does not present appreciable dimensional variations in the different solvents tested, in this case water, methanol, ethanol, acetonitrile and carbonate of propylene.

Example 2 A commercial membrane of Nafion 1170 175 m thick under form of lithium salt is dried and cut into strips of 4 cm x 10 cm side. The Spirally wound membrane is treated with 2 g of dimethylaminotrifluoride of sulfur (CH3) 2NSF3 in 50 ml of THF under reflux and then rinsed. The polymer containing now sulphonated groups in SO2F form is immersed in a solution of 60 mg of sodium salt of hexamethydisilazane in 20 ml of anhydrous diglyme and carried at reflux under argon. After 3 hours, the membrane is extracted from the reaction medium, rinsed THF then treated with a solution of 500 mg of sodium trimethysilanoate in the same solvent. After 48 hours, the membrane is washed with water and with ethanol, then transformed into salt of hydronium by several successive immersions in a solution 2 M nitric acid in water at 60 C. By NMR of the high-resolution solid, lo determines that 32% of the sulfonyl groups in the membrane are made of sulfonimide and 78% as sulfonate. The increase in the volume of the membrane in the presence of water or methanol when immersed in these solvents, including included in boiling temperature, is less than 10%.

Example 3 A copolymer of tetrafluoroethylene and perfluorovinyloxyethane fluoride sulfonyl containing 35 mol% of sulfonated monomer is hot-calendered to form a film 20 microns thick. The compound [Na (Si (CH3) 3NSO2CF2] 2CF2 is prepared for from hexafluoropropane-1,3-disulfonic acid fluoride according to the sequence of following reactions:

[FSO2CF2] 2CF2 + 6 NH3 = 2 NH4F + [(NH4) HNSO2CF2] 2 [(NH4) HNSO2CF2] 2 + Na2CO3 [(Na) HNSO2CF2] 2 + 2 NH3 + H2O + CO2 [(Na) HNSO2CF2] 2 + HN [(Si (CH3) 3] 2 Na [Si (CH3) 3NSO2CF2] 2CF2 + NH3

16 -square sections of 10 cm x 10 cm of this membrane separated by trellises of polypropylene, are immersed in a glass vessel and covered with a solution of 600 mg of the disodium derivative of the sulfamide in 50 ml of diglyme. The mixture The reaction is heated at 125 ° C. for 4 hours under argon. The membranes are then Immersed in a solution of 1 g lithium hydroxide LiOH in 50 ml of methanol, and the hydrolysis of residual SO2F functions in groups sulfonates is continued at 50 C for 4 hours. The reticulated membrane is washed with water deionized, and sodium ions are exchanged with protons by 2M nitric acid. The membrane is stored under air after rinsing with deionized water.

Compounds [FSO2CF2] 20, [FSO2CF2CF2] 20, and [C1SO2CF2CF2] CF2 may similarly be substituted for the fluoride of hexafluoro-propane-1,3-disulfonic compounds as precursors of the bridging agent.

Example 4 The membrane of 20 gm of the copolymer of tetrafluoroethylene and fluoride perfluorovinyloxyethanesulfonyl of Example 3 is treated with a solution 800 mg of the disodium derivative of the sulfonamide of Example 3 and 400 mg of trimethylsilanoate sodium in 50 ml of diglyme. The reaction mixture is brought to 125 ° C. for 20 hours under argon. The membrane is extracted, and washed with deionized water and exchanged by protons as for example 3.

Example 5

- 17 -A copolymer of tetrafluoroethylene and perfluorovinyloxyethane fluoride 35 mol% sulfonyl sulfonated monomer of Example 3 is crosslinked with way similar by immersion in the bridging agent [Na (Si (CH3) 3NSO2CF2] 2CF2 in EXAMPLE 3 The membrane thus crosslinked and containing groups residuals -SO2F is treated with 2 g of sodium salt of the derivative trifluoromethane sulfonamide of formula Na [Si (CH3) 3NSO2CF3] in the diglyme at 110 C. The membrane is rinsed and the sodium ions are exchanged by protons by the acid nitric 2M. The all the sulphonated functions of the membrane are in the form of groups bridging or free sulfonamides:

lo P-SO2N (H) SO2 (CF2) 3SO2N (H) SO2-P
P-SO2N (H) SO2 (CF3) in which P represents the polymer chain.
Example 6 A copolymer of tetrafluoroethylene and perfluorovinyloxyethane fluoride sulfonyl similar to that prepared in Example 3 and containing 35% of monomer sulphonated, is hot-mixed with powdered sodium chloride less than 2 microns and at the 45% volume fraction, and is then granulated about microns in diameter. 5 g of this composite copolymer are treated with 2 g of derivative Sodium hexamethyldisilazane in 30 ml of diglyme at 125 ° C for 3 hours.
hours and residual SO2F functions are reacted with the sodium salt of the derivative trifluoro-methanesulfonamide of formula Na [Si (CH3) 3NSO2CF3] in diglyme at 125.
After washing with water and removal of sodium chloride acting as a porophore, ie, creating

- 18 -porosity after its removal, the polymer is in the form of granules of large surface area allowing quick access to ionic sites.

Example 7 The compound [CF3SO2C (MgCl2SO2CF2] 2CF2 is prepared from the fluoride of acid hexafluoro-propane-1,3-disulfonic acid according to the following reaction sequence:
[FSO2CF2] 2CF2 + 2CF3SO2CH3 + 4LiH? 2H2 + [CF3SO2CH (Li) SO2CF2] 2CF2 [CF3SO2CH (Li) SO2CF2] 2CF2 + 2C4H9Li +4 MgCl2?
[CF3SO2C (MgCl2) 2SO2CF212CF2 + 2C4H10 + 2LiCl1 The reaction sequence is done in the same container ("one pot" synthesis) in the ether dibutyl diethylene glycol (Ferro, USA). A membrane of 20 microns thick and 10 cm x 10 cm prepared from the copolymer of Example 3 is immersed in a solution of 200 mg of chloromagnesium tetrasel of tetrasulfone in 30 ml dibutyl ether anhydrous diethylene glycol. The reaction is carried out under nitrogen deoxygenated at 110 C for 6 hours. The membrane is extracted from the medium reaction, rinsed with THF and the hydrolysis of residual SOIF groups is carried out as previously by lithium trimethylsilanoate. The membrane is washed and exchanged by protons under the conditions of Example 3. Compounds [FSO2CF2] 201 [FSO2CF2CF2] 20, and [C1SO2CF2CF2] CF2 can in a similar manner be substituted to fluoride hexafluoro-propane-1,3-disulfonic acid as precursors agent bridging.

Example 8

- 19 -A 4-trifluorovinyl-benzenesulfonyl fluoride polymer is prepared by radical initiation by benzoyl peroxide in dimethylformamide. The polymer is precipitated in ether. A 12% solution of this polymer in the Cyclopentanone is spread using a template and the solvent is dried under dry air. The polymer film obtained with a thickness of 24 microns. 100 cm2 of this membrane are immersed in a mixture of 200 mg of sodium salt of hexamethyldisilazane and 100 mg of sodium trimethylsilanoate in 10 ml in a mixture of xylene / diglyme (50:50 v / v). The reaction medium is maintained at 80 ° C. for 10 hours and money-The products of the reaction are removed by successive washings in THF, methanol and the water. The exchange of lithium ions by protons gives a material whose conductivity is greater than 10-2 Scm '' at 95% relative humidity.

Example 9 The poly (4-trifluorovinyl-benzenesulfonyl fluoride) of Example 7 is spread form of solution on a polypropylene support to form a 35 micron film thickness, which is then cut into a membrane of 1 meter x 10 cm side. This spiral wound membrane with a stainless steel mesh of metal deployed allowing access to the entire surface of the membrane. This assembly is placed in one 100 ml reactor to which 2 ml of a 0.5 M solution of ammonia is added in the dioxane and 700 mg of DABCO (1,4-diazabicyclo- [2,2,2,] octane) in 80 ml of dimethoxyethane. The reactor is closed and maintained at 115 C for 4 hours under autogenous pressure. After cooling and restoring the pressure ambient, the membrane is separated from the reaction medium and the hydrolysis of SO2F groups residuals is carried out using a solution of 5 g of soda in a ethanol-water mixture

20 -(80:20 v / v). The exchange in proton form is done under the same conditions only for example 8.

Example 10 10 g of a copolymer of tetrafluoroethylene and perfluorinated fluoride vinyloxyethanesulfonyl containing 28 mol% of sulfonated monomer obtained under latex form by emulsion polymerization and 300 mg of lithium nitride in powder of submicron size are dispersed using a blender in 50 ml of Fluorinert FC-75 (3M, USA). The suspension is spread using a template on a strip of stainless steel 25 microns thick and the solvent is evaporated leaving a film of 30 microns thick which is then covered by another strip stainless steel.
The fluoropolymer is crosslinked by hot pressing at 100 Kg.cm 2 and 150 C
during 1 hour. The crosslinking or bridging reaction between the -SO2F functions is product according the following equation:

2 -SO2F + Li3N2 LiF + -SO2N (Li) SO2F-After separation of the strips, residual SO2F functions are hydrolyzed by an aqueous solution of lithium hydroxide, and several washes with water allow to eliminate lithium fluoride, which is a by-product of the reaction of crosslinking or hydrolysis of SO2F groups. The membranes are exchanged by protons by several successive immersions in 2M nitric acid at 60 C.

The same crosslinking process can be applied by replacing the nitride of lithium by aluminum carbide (240 mg per 10 g) to obtain bridges sulfone.

21 -Example 11 A copolymer membrane of tetrafluoroethylene and perfluorinated fluoride vinyloxyethanesulfonyl similar to that of Example 3 is immersed in a solution 0.5 M ammonia in dioxane and left to react for 48 hours. The -SOIF groups are converted into -SO2NH (NH4) groups from of which the sulfonamide is obtained by treatment with a solution of hydrochloric acid and rinsed.
The sodium salt is obtained by immersion in a 10% solution of carbonate of sodium, followed by rinsing with deionized water. The polymer is dried under vacuum and 100 cm2 lo of the membrane are immersed in a solution of hexamethydilsilazane in acetonitrile and refluxed for 48 hours. After separation from middle reaction and drying, the membrane is placed in a reactor containing 100 ml of acetonitrile and 300 mg of fluoride of hexafluoropropane-1,3-disulfonic [FSO, CF 2] 2CF 2, and the reactor is closed and heated at 110 ° C for two hours. After cooling, the membrane is extracted and the groups -SO2F remaining are hydrolyzed with sodium hydroxide solution in the water-alcohol mixture (50:50 v / v) reflux.
Sodium ions are exchanged by protons in a similar way to examples preceded by 2M nitric acid.

In one variant, the sulphonamide functions -SO 2 NH 2 are treated with a excess of dibutyl-magnesium, the membrane is rinsed with anhydrous THF and contact at room temperature in a solution of [FSO2CF2] 2CF2. In both methods, compounds [FSO2CF2] 201 [FSO2CF2CF2] 20, and [C1SO2CF2CF2] CF2 may be substituted for the fluoride hexafluoro-propane-1,3-disulfonic acid.

- 22 -Example 12 An experimental fuel cell is made from a membrane prepared according to Example 3. A nanometric dispersion of platinum on a support of Carbon (Degussa, Germany) is applied on both sides of the membrane by one screen printing technique from a platinum carbon dispersion in a solution colloidal (5% w / w) Nafion 117 in a mixture of light alcohols (Aldrich).
The The system is treated at 130 ° C. to ensure the cohesion of the Nafion particles.
The Current collectors consist of grooved graphite plates for ensure the the distribution of gases. The experimental stack is tested with a hydrogen supply and oxygen at ordinary pressure. The open circuit voltage is 1.2 V
and the curve Current-voltage measured on this circuit shows that 500 mA / cm2 are obtained at the voltage of 0.65 V. The replacement of the platinum of the negative electrode by a alloy platinum-ruthenium 50:50 allows the use as methanol fuel with a current density of 150 mA / cm2 at a voltage of 0.6 V. The permeation of the methanol in these conditions are less than 5 mol / cm 2 = s'.

Example 13 An experimental fuel cell is made from a membrane prepared according to Example 9 in the form of precursors -SO2F. The electrode of carbon platinum of Example 11 is applied on both sides of the membrane by serigraphy of a suspension of this material in a solution of fluoride poly (trifluoromethylstyrene sulfonyl) in 1,2-dichloroethane. The crosslinking -SO2F functions of the complete system is, in a manner similar to that of example 7, WO 99/38897

23 PCT / CA99 / 00078 -by reaction on a mixture of sodium derivative of hexamethyldisilazane and sodium trimethylsilanoate in 10 ml in an o-xylene / diglyme mixture (50:50 v / v). After crosslinking, the Nd ions of the membrane and the binder of the electrodes are exchanged with protons using concentrated hydrochloric acid and rinsing.

The experimental fuel cell using this assembly has performances similar to those obtained for the battery described in Example 12.

Example 14 Electrolysis of sodium chloride is carried out in a two-cell lo compartments separated by a membrane prepared according to Example 3, the anode being of type DSA ("dimensionnaly stable electrode") and made of titanium coated a RuO2 ruthenium oxide layer, in contact with the membrane, the cathode being in nickel. The ohmic drop for 2 A / cm2 is 0.4V, and the ion permeation OH- to through the membrane is less than 8.5 gmol / cm 2 s.

Example 15 The membrane prepared according to Example 4 is used for the preparation of ozone by electrolysis of water on a lead dioxide anode. The cathode is a platinum grid, the two electrodes being pressed onto the membrane whose side cathodic is immersed in water. Faradic efficiency in ozone and 20%
under 4.5V.

Example 16

- 24 -The porous ion exchange resin prepared in Example 5 is used as the chemical reaction catalyst. In active proton form after dehydration under empty, the resin catalyzes the reactions of Friedel-Craft, the esterifications, Acetalizations etc. To an equimolecular mixture of anisole and acetic anhydride are added 3% in weight of the resin in acid form. The formation reaction of the 4-methoxyacetophenone is complete in 45 minutes at room temperature.

Proton exchange for transition ions and earth metals rare, in particular La + 3 and Y + 3 gives a catalyst for the Friedel-Craft and lo cross-aldolization.

Has an equimolecular mixture of cyclopentadiene and vinyl methyl ketone (10 mmol in 30 cc of dichloromethane) are added 5% by weight of the resin under form Y + 3 dried under vacuum at 60 C. The formation reaction of the compound of Diels-Alder condensation is complete at 25 C in 30 minutes, the ratio endo / exo being close to 90:10.

In both cases, the catalyst is removed by simple filtration and reusable.
Although the present invention has been described using implementations specific, it is understood that several variations and modifications may add to implemented, and the present application is intended to cover such changes, uses or adaptations of the present invention according to, in general, the principles of invention and including any variation of the present description which will become known or WO 99/38897

25 PCT / CA99 / 00078 -Convention in the field of activity in which this invention, and which can be applied to the essential elements mentioned above, in agreement with the scope of the following claims.

Claims (29)

1. Process for crosslinking sulfonyl groups of a sulfonated polymer wherein at least a fraction of the crosslink bonds carry a ion charge, the method comprising contacting the polymer with a crosslinking allowing the reaction between 2 sulphonyl groups coming from chains polymers adjacent ones, to form the crosslinking bonds, the bonds of crosslinking are:
P-SO2-Y-(M+)-SO2-P'; Where P-SO2(M+)Y-SO2-(Q-SO2),Y-(M+)SO2-P' in which - P and P' are identical or different and form part of a polymer chain;

- Y is N or CR where R is H, CN, F, SO2R 3, C1-20 substituted or unsubstituted alkyl substituted;
C6-20 substituted or unsubstituted aryl or C2-20 substituted or unsubstituted alkylene substituted, the substituent being a halogen or halogens, and in which the chain comprises a or some substituents chosen from F, SO2R where R is defined above, aza, oxa, thia and dioxathia;

- R3 is F, C1-20 substituted or unsubstituted alkyl; C6-20 substituted aryl or non-substituted or C2-20 substituted or unsubstituted alkylene, the substituent being one or more halogens;

- M+ is H+; a metal cation selected from an alkali metal, an alkaline metal earthy, a transition metal and a rare earth; an organometallic cation or a cation organic onium;

- Q is a divalent radical C1-20 alkyl, C1-20 oxaalkyl, C1-20 azaalkyl, C1-20 thiaalkyl, C6-20 aryl or C6-20 alkylaryl, each is optionally substituted with a or some halogens, and in which the chain is substituted with one or more oxa, aza substituents or thia; and remainder 0 or 1, the divalent radical and the sulfonated polymer are partially or totally fluorinated. 2. Process according to claim 1, in which the organometallic cation or the organic cation onium is optionally substituted by radical(s) organic choose from:

- the proton, alkyl, alkenyl, oxaalkyl, oxaalkenyl radicals, azaalkyls, azaalkenyls, thiaalkyls, thiaalkenyls, dialkylazo, silaalkyls optionally hydrolyzable or optionally hydrolyzable silaalkenyl radicals, the radicals are linear, branched or cyclic and have 1 to 18 carbon atoms;

- cyclic or heterocyclic aliphatic radicals with 4 to 26 carbon atoms carbon optionally having at least one side chain having one or more heteroatoms selected from nitrogen, oxygen and sulfur; and - aryls, arylalkyls, alkylaryls or alkenylaryls with 5 to 26 carbon atoms carbon having optionally one or more heteroatoms in the aromatic ring or in a substitute. 3. Process according to claim 1, in which the organometallic cation is selected from a metallocenium, an arene-metallocenium, an alkylsilyl, an alkylgermany or an alkyltin. 4. Process according to claim 1, in which the organic onium cation is chosen from an oxonium R"O+, an ammonium NR"+, an amidinium R"C(NHR")2+, an guanidinium C(NHR")3+, a pyridinium C5R"N+, an imidazolium C3R"N2+, a triazolium C2R"N3+, an imidazolinium C3R"N2+, a sulfonium SR"+, an phosphonium PR"+, an iodonium IR"+ and a carbonium (C6R")3C+, in which R" is a radical organic as defined in claim 2, and when a cation organic onium comprises at least two radicals R" different from H, these radicals form together one aromatic ring or not, optionally including the center bearing the load cationic. 5. Process according to claim 1, in which a labile group is bound to the sulphonyl groups before carrying out the crosslinking. 6. Process according to claim 5, in which the labile group is selected from F, Cl, Br, an electrophilic heterocycle N-imidazolyl, N-triazolyl and R2SO3, R2 being an optionally halogenated organic radical, the organic radical is chosen among :

- the proton, alkyl, alkenyl, oxaalkyl, oxaalkenyl radicals, azaalkyls, azaalkenyls, thiaalkyls, thiaalkenyls, dialkylazo, silaalkyls optionally hydrolyzable or optionally hydrolyzable silaalkenyl radicals, the radicals are linear, branched or cyclic and have 1 to 18 carbon atoms;

- cyclic or heterocyclic aliphatic radicals with 4 to 26 carbon atoms carbon optionally having at least one side chain having one or more heteroatoms selected from nitrogen, oxygen and sulfur; and - aryls, arylalkyls, alkylaryls or alkenylaryls with 5 to 26 carbon atoms carbon having optionally one or more heteroatoms in the aromatic ring or in a substitute. 7. Process according to claim 1, in which the crosslinking agent understand an organometallic cation selected from organo-lithium, organo-magnesium and organo-aluminum, or a compound of general formula (M+)A2Y-, (M+)AY-SO2Y-A(M+), or (M+)AY-SO2QY-A(M+), wherein Y, Q and M+ are as defined in claim 1, and A
is chosen from Si(R')3, Ge(R')3 and Sn(R')3, where R' is C1-18 alkyl. 8. Process according to claim 7, in which A is a group tri(C1-18)alkyl silyl. 9. Process according to claim 7, in which the crosslinking agent is selected from the group comprising: Li3N, C3Al4, [(CH3)3Si]2NLi, [(CH3)3Si]2NNa, [(CH3)3Si]2NK, NH3 + 3 DABCO, CF3SO2C[(CH3)3Si][Li(TMEDA)]2, (CH3)3CNH2 +
3 TEA, NH2SO2NH2 + 4 TEA, [[(CH3)3Si](Li)N]2SO2, [(TMEDA)(Mg)N]2SO2, CH3Li, (CH3)3Al, NH2Li, NH2Na, NH2K, [[Si(CH3)3](Li)NSO2]2CF2, [Li[Si(CH3)3]NSO2CF2]2CF2, [(Li)Si(CH3)3NSO2CF2], [Li[Si(CH3)3]NSO2CF2CF2]2O, SO2Cl2 + 3 DABCO, SO2(imidazole)2, [FSO2CF2]2 + 3 TEA, (ClSO2CF2)CF2 + 3 DABCO and (FSO2CF2CF1)2O + 3 DABCO. 10. Process according to claim 1, in which the uncrosslinked polymer is molded before being cured. 11. Process according to claim 1, in which the uncrosslinked polymer is mechanically mixed with the crosslinking agent, pressed and heated. 12. Process according to claim 1, in which the uncrosslinked polymer is molded and contacted with a solution of the crosslinking agent in a solvent inert. 13. Process according to claim 12, in which the crosslinking density is controlled by solvent immersion time, solvent temperature, or the concentration of crosslinking agent in the solvent. 14. Process according to claim 12, in which the solvent is chosen from the group comprising: aromatic hydrocarbons, hydrocarbons and ethers partially or totally halogenated aliphatics, THF, ethers alkyl mono-, di-, tri- and tetraethylene glycols, the selected tertiary alkylamides among the DMF, N-methylpyrrolidone, tetramethylurea and its cyclic analogues, N-alkylimidazoles, tetraalkylsulfamides, and mixtures thereof. 15. Process according to claim 1, in which the uncrosslinked polymer is molded and contacted with the crosslinking agent and a non-ionogenic agent crosslinker to form the end groups -SO3-(M+), or -[SO2YSO2R]-(M+), R is a organic radical as defined in claim 2 and optionally halogen. 16. Process according to claim 15, in which R is halogenated. 17. Process according to claim 15, in which R is perfluorinated. 18. Process according to claim 15, in which the uncrosslinked polymer is molded and contacted sequentially or simultaneously with the crosslinking and the non-crosslinking ionogenic agent. 19. A method according to claim 15 wherein the non-ionogenic agent crosslinker is chosen from (CH3)3SiO-(M+) and [(CH3)3SiNSO2R F]-(M+) where M+ is such that defined at the claim 1 and RF is alkyl, oxaalkyl, azaalkyl or thiaalkyl essentially perfluorinated with 1 to 12 carbon atoms. 20. A method according to claim 1 wherein a reinforcing agent is added to the polymer before crosslinking. 21. Electrochemical cell in which a membrane comprising a crosslinked polymer as obtained according to claim 1 is used as electrolyte solid. 22. Cell according to claim 21 comprising a fuel cell, a water electrolyser, a chlorine-soda battery, an electrochemical battery recovery of salts or acid, or an ozone-generating battery. 23. Cell according to claim 22 comprising the fuel cell in which M+ is a hydrated proton and the positive electrode contains a reducing catalyst of oxygen. 24. Sulfonated polymer obtained according to the process defined in claim 1 having some or all of the cross-linked sulfonyl groups, and in which at least a fraction of the crosslinking bonds carry an ionic charge, the links of crosslinking are:

P-SO2-Y-(M+)-SO2-P'; Where P-SO2(M+)Y-SO2-(Q-SO2)r Y-(M+)SO2-P' in which - P and P' are identical or different and form part of a polymer chain;

- Y is N or CR where R is H, CN, F, SO2R 3, C1-20 substituted or unsubstituted alkyl substituted;
C6-20 substituted or unsubstituted aryl or C2-20 substituted or unsubstituted alkylene substituted, the substituent being a halogen or halogens, and in which the chain comprises a or some substituents chosen from F, SO2R where R is defined above, aza, oxa, thia and dioxathia;

- R3 is F, C1-20 substituted or unsubstituted alkyl; C6-20 substituted aryl or non-substituted or C2-20 substituted or unsubstituted alkylene, the substituent being one or more halogens;

- M+ is H+; a metal cation selected from an alkali metal, an alkaline metal earthy, a transition metal and a rare earth; an organometallic cation or a cation organic onium;

- Q is a divalent radical C1-20 alkyl, C1-20 oxaalkyl, C1-20 azaalkyl, C1-20 thiaalkyl, C6-20 aryl or C6-20 alkylaryl, each is optionally substituted with a or some halogens, and in which the chain is substituted with one or more oxa, aza substituents or thia; and r is 0 or 1, the divalent radical and the sulfonated polymer are partially or totally fluorinated. 25. Polymer according to claim 24 in which the organometallic cation or the organic onium cation is optionally substituted by one or more radicals organic chosen from:

- the proton, alkyl, alkenyl, oxaalkyl, oxaalkenyl radicals, azaalkyls, azaalkenyls, thiaalkyls, thiaalkenyls, dialkylazo, silaalkyls optionally hydrolyzable or optionally hydrolyzable silaalkenyl radicals, the radicals are linear, branched or cyclic and having from 1 to 18 carbon atoms;

- cyclic or heterocyclic aliphatic radicals with 4 to 26 carbon atoms carbon optionally having at least one side chain having one or more heteroatoms selected from nitrogen, oxygen and sulfur; and - aryls, arylalkyls, alkylaryls or alkenylaryls with 5 to 26 carbon atoms carbon having optionally one or more heteroatoms in the aromatic ring or in a substitute. 26. Polymer according to claim 24 in which the organometallic cation is selected from a metallocenium, an arene-metallocenium, an alkylsilyl, an alkylgermany and an alkyltin; and the organic onium cation is selected from a oxonium R"O+, an ammonium NR"+, an amidinium R"C(NHR")2+, a guanidinium C(NHR")3+, a C5R"N+ pyridinium, a C3R"N2+ imidazolium, a triazolium C2R"N3+, an imidazolinium C3R"N2+, a sulfonium SR"+, a phosphonium PR"+, an iodonium IR"+ and a carbonium (C6R")3C+, in which R" is defined as a radical organic as defined in claim 25, and when a cation organic comprises at least two radicals R" different from H, these radicals form together one aromatic ring or not, optionally including the center bearing the load cationic. 27. Polymer according to claim 24 derived from at least one of the monomers next :

in which - X is F, Cl or CF3;

- n varies between 0 and 10 inclusive;
- E is absent, O, S or SO2, - Z is H or F; and - L is a labile group. 28. Sulfonated polymer obtained according to the process of claim 20. 29. Use of a crosslinked polymer according to claim 24 in a process chlorine-soda electrolysis, as a separator in a preparation electrochemical organic and inorganic compounds, as a separator between an aqueous phase and an organic phase, or as a catalyst for Diels-Alder additions, reactions Friedel-Craft, aldol condensations, cationic polymerization, esterifications, and the formation of acetals.