DE2709097A1 - PHOSPHONIZED FLUORTELOMERS - Google Patents

Description

In technical chlorine alkali cells for the production of Chlorine, hydrogen and sodium hydroxide are made from sodium chloride to separate the anode chambers from the cathode chambers usually asbestos diaphragms are used. Such diaphragms are generally satisfactory however, they have a high electrical resistance, so that cells equipped with them have an undesirably high electrical energy requirement. From U.S. Patent 3,853,721 are asbestos diaphragms treated with certain ion exchange resins are also known.

The invention relates to phosphonated fluorotelomers of the general formulas I or II

(D

(H)

in which Y ₁ »Y ₂ * Y ₅ and Y * are identical or different and each represent an alkyl radical with 1 to 10 carbon atoms» an alkyl radical with 1 to 10 carbon atoms substituted by at least one alkyl radical with 1 to 4 carbon atoms or a monovalent metal » X is a homo- or cotelomeric portion

(a) one or more monoethylenically unsaturated monomers » that (the) fully by fluorine atoms or a combination of at least one fluorine atom and chlorine or Bromine atoms is (are) substituted »and / or

(b) a perfluoroalkyl vinyl ether, the alkyl radical of which has 1 to carbon atoms »

represents »

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FF 6080 A

Z * and Z _{2 are} identical or different and are each a divalent metal »an alkylene radical with 1 to 10 carbon atoms or an alkylene radical with 1 to 10 carbon atoms substituted by at least one alkyl radical with 1 to 4 carbon atoms * where Z ₂ also consists of Y ₁ and Y «can exist» and
η has a value from 2 to 500.

"Cotelomeric portion" in Formulas I and II means one telomeric part consisting of two or more different types of monomer units »while" homotelomeric part " means a telomeric portion consisting of one kind of monomer units.

The term "fully substituted" means that there are few or no CH bonds in the telomeric portion. Although this is preferred, the telomere need not be ( ^{in the} strict sense) fully substituted.

The telomers of the formula I can also be in the form of salts of trivalent metals which have a crosslinked structure have »in one or two metal valence (s) of one fluorotelomer molectile and the remaining valence (s) of another Fluorotelomer molecules are used.

They salts of fluorotelomers with monovalent »divalent ones and trivalent metals can be generated in situ in a chlor-alkali cell "in which the fluorotelomer is used" will.

Those fluorotelomers of the formulas I and II "which are not hydrophilic or just barely hydrophilic" can be converted into hydrophilized the free acid forms or in metal salts are »as explained below.

They are preferred phosphonated fluorotelomers according to the invention

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because of their ease of manufacture »their good ion exchange capacity and their low solubility in cell fluids are those fluorotelomers of the formula I those

X means a telomeric fraction of tetrafluoroethylene (TFE) »

T ₁ * T ₂ * T, and T. each represent an ethyl group or each a butyl group, or T ₁ and T ₂ each represent an ethyl group and T * and T. each represent a butyl group and

η has a value from 20 to 100 *

Those are also preferred because of their low melting points and easy processability into diaphragms Fluorotelomers of the formula I »where

Z is a cotelomeric portion of tetrafluoroethylene and one Ferfluoropropyl vinyl ether in a weight ratio of 83:17 or a telomeric proportion of hexafluoropropylene represents «

T ₁ * T ₂ * T, and Tj each represent an ethyl group and η has a vert of 20 to 100.

For certain purposes, the fluorotelomers of the formula II * are also preferred for those

I a cotelomeric portion of tetrafluoroethylene and hexafluoropropylene (HFP) in a weight ratio of 5: 1 means »

Z _{1 represents} an ethylene group » Z _{2 represents} two ethyl groups (diethyl) and

η has a value from 20 to 100.

Part »percentages and ratios relate to

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lying frame on weight »unless otherwise stated is. In practical use, the preferred telomers are converted into the corresponding ones in an electrolytic cell Converted to sodium salts.

In addition to the pluortelomers, the invention also relates to methods for their production in the ester »acid and salt forms» diaphragms and membranes produced from them, as well as the Use of such diaphragms and membranes.

The invention will now be explained in more detail.

In contrast to conventional pluortelomers, those are according to the invention Pluortelomers are hydrophilic or can be easily hydrophilized. "Hydrophilic" in this context means » that the telomeres absorb water rather than repel it. In more specific respects, "hydrophilic" means "that the telomere has a water contact angle of 0 ° to about 50 ° (determined according to the method and with the help of the gate direction » which is described on page 137 of "Contact Angle" Wettability and Adhesion "" American Chemical Society "1964" are).

Produced from mixtures of the hydrophilic pluortelomers according to the invention with inert fiber materials and binders Diaphragms or membranes made from these pluortelomers, preferably with an inert fabric carrier can be used in ion exchange processes »especially those» where hydrophilicity is desired or necessary » will. Such diaphragms used in chlor-alkali cells surprisingly have a significantly smaller one electrical resistance than conventional asbestos diaphragms. Therefore, with the help of cells, which with the diaphragms containing hydrophilic pluortelomers according to the invention are equipped »despite operation at

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lower voltages have the same chlorine, hydrogen and alkali production capacity as when using asbeat diaphragms achieve. In addition, the fluorotelomers according to the invention have the diaphragms produced generally have a higher resistance to the effects of the electrolytic cell fluids » a longer service life and a higher dimensional stability or dimensional accuracy than the conventional Asbestos diaphragms.

Production of the phosphonated fluorotelomers

You can phosphonated pluortelomers according to the invention be prepared by adding a suitable mono-ethylenically unsaturated fluoromonomer with a compound converts »which is capable of forming a phosphorus-containing free radical of the general formula below

O
YO-P

ότ

in which T. and Y ₂ mean identical or different radicals »preferably alkyl radicals with 1 to 10 carbon atoms or alkyl radicals with 1 to 10 carbon atoms» which are substituted by at least one alkyl radical with 1 to 4 carbon atoms ».

Examples of suitable fluoromonomers are tetrafluoroethylene (TFE) * monochlorotrifluoroethylene, dichlorodifluoroethylene, monobromotrifluoroethylene, Dibromodifluoroethylene »hexafluoropropylene (HFP) and perfluoroalkyl vinyl ethers» their alkyl radicals 1 to 10 Have carbon atoms.

These fluoromonomers can be used individually to produce homotelomeric forms or in combinations of two or more

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-J.

Types of monomers for the formation of cotelomeric forms of the phosphonated Fluorotelomers are used.

Examples of compounds having the ability to generate the required phosphorus-containing free radical are

Tetraalkyl hypophosphates (their alkyl radicals 1 to 10 carbon have atoms) »

letraalkylpyrophosphites (their alkyl radicals 1 to 10 carbon have atoms) »

Cycloalkyl hypophosphates (their alkyl radicals 1 to 10 carbon have atoms) »

Cycloalkylpyrophosphites (their alkyl radicals 1 to 10 carbon atoms have) and

the compounds of the general formula

0
T ₁ O — PPP — OT.

• ι ι

T ₂ O OT ₃

in which T ₁ * T ₂ »T ~ and T. each have the meanings given for formula I. Mixtures of these compounds can also be used.

The reaction of the fluoromonomer with the radical-forming compound takes place according to the following reaction equations:

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OR OR
(4)

OR OB
i «.U <L« initiator O
j 2 RO-P OR Tetraalkyl
pyrophosphite free radical O O O ti
2 RO-P + Plus monomer ->
t
OR RO-P (X) = - P-OR
t ^U I
OR OR free radical Telomeres

0 0
η η
2 RO-P-P-OR initiator ^ O
2 RO-P II *
OR OR OR Tetraalkyl
hypophosphate free radical 0
If
2 RO-P * + pluox monomer
f OO
η η
RO-P frX) = ^p - ° ^R
ft A * m OR OR OB. free radical Telomeres

The telomers of the formula II can after the same reactions using cycloalkyl hypophosphates or Cycloalkylpyrophoepb.iten as radical-forming compounds getting produced.

You implementations according to equations (4) and (5) are thereby

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6080 a 7709097

- ♦ f.

made "that one" makes a 1 to 50 wt .- # solution of the respective hypophosphate or pyrophosphite in a halogenated hydrocarbon. You solution will then with 0.1 to 10% by weight of a radical-forming initiator (such as di-tert-butyl peroxide or azo-bis-isobutyronitrile) ▼ replaced.

The solution is then placed in a pressure vessel and the gaseous or liquid fluoromonomer is added. The added one The proportion of fluorinated monomers depends on the desired chain length of the telomer (i.e. the vert η in formulas I and II) and is usually in the range of 2 to 500 hol per 2 moles Pyrophosphite or hypophosphate.

The vessel is then closed, heated to 50 to 300 ⁰ C (preferably from 60 to 120 ° C) and as long maintained under shaking at these temperatures until the pressure in the vessel drops (from which it follows that the reaction is complete). The vessel is then opened, the dispersion of the phosphonated pluortelomer is removed and the solvent is evaporated from the dispersion. The product obtained is washed out with methanol and dried and is then ready for use.

The physical state of the pluortelomer isolated in this way can range from a viscous liquid to a waxy pest.

The mixed telomers according to the invention, ie those telomers in which Y ₁ and Y ₂ are different from Y and Y., can be prepared according to the following reaction equation as an example:

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PP 6080 A 7709097

O (6) CH ₅ (CHg) ₃ O-P P-OCH ₂ CH ₃

CH ₃ (CH ₂ ) ₃ 0 OCH ₂ CH ₃

bleached tetraalkyl hypophosphate

initiator

CH ₃ (CHg) ₃ OP * CH ₃ (CH ₂ ) _3-0

free radical CH ₃ CH ₂ OP *

CH ₃ CH ₂ -

free radical

O η

CH ₃ (CHg) ₃ -OP * CH, (CHo), 0

CH, CH ₉ 0-P

CH ₃ CH ₂

—0

Pluormonomeres

It

CH

₃ (CH ₂ ) ₃ -O-F

JH ₃ (CH ₂ ) _: O
PO-CH ₉ CH

CH ₂ CH ₃

Telomeres

The conversion according to equation (6) takes place in the same way like those of equations (4) and (5)

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When the free radicals are formed, some other types of end groups, such as carboxyl groups, can be introduced. However, this may reduce the ability of the fluorotelomer end that is still present "described type to ensure the advantages of the invention are not impaired.

Mixed tetraalkyl hypophosphate used according to reaction equation (6) can according to Bull.Acad.Polon.Sei. " Ser.Sci.Chim., 13 (1965). Page 253 and Z. Anorg.Allg.Che. » 288 (1956), p 171 are produced.

The metal salts of the phosphonated pluortelomers can thereby to be produced »that a telomer is hydrolyzed (saponified) to the free acid form and then the hydrogen atoms of the carboxyl groups replaced by metal atoms by metathesis.

To produce a fluorotelomer salt, one-, two- or trivalent metals can be used. Specific examples of suitable metals are sodium »potassium, lithium, Calcium »Barium» Magnesium »Aluminum» Manganese »Iron» Cobalt »Copper» Zinc and Cadmium.

The pluortelomers according to the invention are usually used in the ester form for the production of diaphragms for chlor-alkali cells used. If the diaphragm with the sodium hydroxide contained in the cell fluid (electrolyte) comes in contact »the ester form changes to the sodium salt form. Furthermore, the ester form can easily be saponified (e.g. with suitable acids) can be converted into the acid form.

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Division of diaphragms from the telomeres

For any purpose suitable diaphragms containing a phosphonated fluorine according to the invention can telomer be made from a composition »which

a) one or more pluortelomer (s) of the formula 1 »

b) a fiber material »which serves as a base or support for the diaphragm»

c) a fluoropolymer as a binder and

d) a liquid carrier
contains.

The composition can also contain conventional auxiliaries »such as wetting agents» surface-active agents or foam inhibitors » included in the usual proportions.

The manufacture of a diaphragm from such a composition (hereinafter the expression "Hasse" is used for this) can be done by first deagglomerating the fibers of (b) and then separating them of the carrier creates a mat from the fibers. The methods of paper production are preferably used for this. Afterward the mat is heated up to the melting or softening temperature of the binding agent »whereby a coherent Structure is given »that can be used directly for the intended purpose.

The diaphragm mat can be produced directly on the wire mesh cathode of the electrolysis cell in which it is to be used and then heated until the binder melts or softens. The resulting diaphragm can be used directly without further treatment. At in

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PP 6080 A

Diaphragms produced in this way must comply with the manufacturer's regulations in terms of permeability »Stromaüsbeüte and dimensional stability (dimensional accuracy) to be fulfilled. These regulations depend on the manufacturer, on each cell type used »on the electrical energy demand of the cell and on other factors. For the production of The same apply to diaphragms made from the masses according to the invention technical principles as for the production of conventional asbestos diaphragms.

Any fiber material can be used which corresponds to the firing temperatures to be used and the effects of the Resist environment »in which the membrane is to be used». Examples of suitable fiber materials are Asbestos »glass fibers * fluoropolymer fibers» such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene / hexafluoropropylene copolymers, and potassium titanate fibers. Mixtures of such fiber materials can also be used. For electrolytic cell diaphragms Asbestos is the preferred fiber material. Particularly preferred is a chrysotile asbestos and its fibers an average diameter (determined with an electron microscope) of about 200i and an average length of have about 70 mm. The asbestos fibers are preferably completely or practically completely with those according to the invention Fluorotelomer coated.

The fluoropolymer used as a binder can also be any fluoropolymer which can be influenced by the Environment in which it is intended to be used. Examples of suitable fluoropolymers are polytetrafluoroethylene, Tetrafluoroethylene / hexafluoropropylene copolymers (with all Monomer proportions) »polyvinyl fluoride» polyvinylidene fluoride and vinylidene fluoride / ccafluoropropylene copolymers (with all monomer proportions). Man can also use mixtures of binders.

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- κ

The tetrafluoroethylene / hexafluoropropylene copolymers are Preferred as a binder for electrolytic cell diaphragms due to their inert nature.

Any liquid which has the chemical or physical properties of the Diaphragm not noticeably impaired. Examples of such liquids are water »chlorinated hydrocarbons» Methanol »hexane and sodium chloride solution. When the hate about making an electrolytic cell diaphragm should serve »one preferably uses 15-year-olds as a carrier aqueous sodium chloride solution there is such a solution contributes »to keeping the fiber material in suspension.

The components of the masses are preferably present in the following concentrations:

(a) Telomeres: 10 to 90 wt .- # (especially 40 to 60% by weight of the total of (a) and (b);

(b) Binder: 10 to 90 parts by weight (especially 40% by weight) to 60% by weight of the total of (a) and (b)>

with (a) plus (b) 10 to 90% by weight preferably 20 to 25 wt. 5t) of the totality of (a) «(b) and (c) make up;

(c) Fiber material: 10 to 90 parts by weight (especially 70%) to 80 wt .- ^) of the total of (a), (b) and (c);

(d) Carrier: remaining portion.

The masses contain 0.01 to 3 wt. -36 (preferably about 1 wt. Ji) solids.

In the case of modified compositions according to the invention, suitable proportions of the telomer and binder can be mixed and the

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sermaterial as well as the carrier of the mixture obtained immediately add Hasse to a slide pragma before processing.

Such masses each contain 1 to 99 parts by weight (preferably 10 to 90% by weight of telomeres or binders (based on on the totality of telomer and binder).

The phosphonated fluorotelomers of the invention are suitable calibrated particularly well for the production of diaphragms for electrolysis cells · especially chlor-alkali cells. One can but also produce membranes from the fluorotelomers »with the help of which various substances (either electrolytically or non-electrolytically) can be separated from each other. They can be used, for example, in ion exchange processes (as in the desalination of sea water) and for the production of osmotic methods and dialysis processes Use suitable semipermeable membranes (such as Donnan's dialysis). The telomers can also be used to produce of - especially in alkaline cells - to be used battery partitions. Fluorotelomere of Formeini and II »where η has a value from 2 to 20» can also be used for passivating metals.

Membranes differ from diaphragms in that they are essentially impermeable to water and, on the other hand, in dependence are selectively permeable to either cations or unions by their permselectivity. Semipermeable membranes also have a very low porosity »which allows the passage of liquids» those of however, inhibits relatively large substances (such as the particles of some colloids). Diaphragms, on the other hand, allow considerable amounts of liquid through »while inhibiting the passage of unions or cations.

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Membranes can be manufactured and used using conventional methods. One can use the phosphonated fluorotelomers of the invention to form membranes, which preferably have a thickness of 0.1 to 0.25 am (typical Diaphragm thicknesses are 2.5 mm). Such thin membranes usually maintain a tissue (preferably with a coarse-meshed structure) from a material that is inert to the environment during operation to become. Fluorocarbon polymers (such as polytetrafluoroethylene) are suitable as carriers for phosphonated pluortelomers according to the invention, which are for use in chlor-alkali cells are provided.

The following examples are intended to explain the invention in more detail » but without restricting them. In the examples, the diaphragms produced are each while maintaining a Space between the cathode and anode of 0.635 cm (1/4 in.) Inserted. Typical conventional asbestos diaphragm cells require a voltage of at this electrode spacing to achieve a current density of 0.204 A / cm 3.5 to 3.7 volts. Although the diaphragms in the examples are produced in plate form and then in the electrolytic cells are installed, corresponding results are achieved »if the diaphragms are placed on one of the cells in the cell Manufactures wire mesh cathode.

example 1

(A) A pressure vessel is charged with the following components:

1) Trichlorotrifluoroethane 160 parts

2) Solution of 6.45 parts of tetraethyl pyrophosphite in 20 parts of trichlorotrifluoroethane

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3) Solution of 2 parts of di-tert-butylperozide in 20 parts trichlorotrifluoroethane

4) Tetrafluoroethylene 50 parts

The batch is placed under nitrogen, and after the vessel has been closed, it is heated to 100 ^° C. and kept at this temperature for 2 hours. The temperature is then increased to 120 ° C. and held at this value for 2 hours. Finally, the temperature is increased to 140 ^° C. and the batch is kept at this temperature for 2 hours. Thereafter, a pressure drop within the vessel indicates that the reaction has been completed.

You open the vessel and transfer its contents into one Distillation device »in which the solvent at 40 to 50 ° C is distilled off.

The waxy solid obtained is washed twice with methanol and then dried in vacuo.

(B) The following components are produced:

1) solution of 363 parts of sodium chloride in 2420 parts of distilled water and

2) mixture of

(a) 5 »5 parts of an aqueous dispersion of a tetrafluoroethylene / hexafluoropropylene (85:15) copolymer with a solids content of 55 pounds and

(b) 3> O3 parts of the product of (A) in 30 parts Isopropanol.

Put the solution (1) in a knife and add 24 »2 Parts of asbestos fibers (mean diameter 200 i, mean length 70 mm; Commercial product Chlorbestos SP-25 from

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? 709097

Johns-Manville Co.). Then the mixture (2) is added. The carrion is 2 Hin. mixed at medium speed and then to deagglomerate the Asbestos fibers flushed with air for 2 hours.

The resulting mixture is then diluted with the same volume of distilled water and poured into a plate form from which the liquid is then drawn off at a vacuum of 250 mm. The mat obtained is washed by sucking 2000 parts of distilled water through it, dried at 95 ^° C. for 1 hour and dried for 30 hours. Fired at 275 ^{° C.} A 2.5 mm thick product is obtained.

Then the hat is 2.75 hours. In 5 # aqueous Sodium hydroxide solution boiled and then dried.

(C) The hat produced according to (B) is in the diaphragm position applied to the cathode of a chloralkaliζeile. When operating the cell, a diaphragm area is required to achieve a current density of 0.204 A / cm average voltage of 3.7 volts required.

example

(A) Han provides a pluortelomer according to Example 1 (A), however using the following approach:

1) Solution of 16.5 parts of dibutyl diethyl hypophosphate in 200 parts of trichlorotrifluoroethane

2) Azo-bis-isobutyronltrile 4t1 parts

3) Tetrafluoroethylene 50 parts

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6, 95 Parts 40 Parts 1, 11 Parts 20th Parts.

- 34-

Moreover, the reaction temperature is maintained for 3 h. At 65 ⁰ C and then for 3 hrs. At 9O ⁰ C.

(B) There are 3 * 7 parts of the asbestos fibers in Example 1 (B) used type and 370 parts of distilled water in a niche. Bann adds a mixture of the following Components:

Dispersion of (A)
Methanol

aqueous dispersion of a tetrafluoroethylene / hexafluoropropylene (85:15) copolymer (55 % solids)

distilled water

The batch is mixed for 10 minutes at low speed and the resulting slurry is diluted with it 1558 parts of distilled water. The resulting slurry becomes the liquid in one Büchner funnel sucked out at a vacuum of 250 mm.

The mat obtained is dried under low pressure for 5 minutes at 25 ^° C. and then for 30 minutes at 95 ^° C. and finally ^{fired at 275 °} C. for 30 minutes. A product 2.5 mm thick is obtained.

Then the mat is 90 minutes in aqueous 5 pounds Boiled caustic soda.

(C) The mat produced according to (B) is in the diaphragm position applied to the cathode of a chlor-alkali cell. When operating the cell is for achieving a current density of 0.204 A / cm diaphragm area medium voltage of 3ι26 volts required.

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If Example 2 is repeated with the exception that in approach (A) instead of tetrafluoroethylene, the same Amount of a 5O: 16 mixture of tetrafluoroethylene and Bromotrifluoroethylene used, practically the same results were obtained.

example

(A) A fluorotelomer is prepared according to Example 1 (A)> but using the following approach:

1) Solution of 12 parts of tetraethyl pyrophosphite in 120 parts of trichlorotrifluoroethane

2) Solution of 3 »65 parts of di-tert-butyl peroxide in 40 parts of trichlorotrifluoroethane

3) Mixture of 50 parts of tetrafluoroethylene and 10 parts of perfluoropropyl vinyl ether.

Moreover, the reaction temperature is maintained UO 2 hrs. At 100 ⁰ C, followed by 2 more hours at 120 ° C and finally a further 2 hours. ⁰ C.

(B) A slurry of the following ingredients is flushed with air for 2 hours:

Distilled water 2420 parts

Sodium chloride 263 parts

asbestos

(same type as in example 1) 24 »2 parts.

The slurry is then mixed with a Dispersion of the following ingredients:

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709836/0921

1) Sispersion -of 3 * 03 parts of the telomer of (A) in 14.91 parts of methanol

2) Powdered tetrafluoroethylene / hexafluoropropylene (85:15) copolymer 3 »03 parts.

The slurry becomes 30 hin. flushed with air and then in a niche 1 min. at medium speed mixed.

The slurry is poured into a plate form and a mat is created from it by sucking off the liquid under a vacuum of 250 mm Hg. The mat is washed by sucking 2000 parts of distilled water through it, pressed between sheets of blotting paper and then ^{held at 135 °} C. for 5 minutes between the sheets of paper.

The dry 1.5 mm thick mat obtained is finally ^{fired at 275 °} C. for 30 minutes.

(C) The mat produced according to (B) is in the diaphragm position applied to the cathode of a chlor-alkali cell. When operating the cell is for achieving A current density of 0.129 A / cm requires an average voltage of 2.96 volts.

If example 3 is repeated with the exception that in approach (A) instead of the fluoromonomers used there the equimolar amount of a 80: 20 mixture of tetrafluoroethylene and hexafluoropropylene is achieved you get practically the same results.

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Example 4

(A) A pluortelomer is prepared according to Example 1 (A), but using the following approach:

1) Solution of 12 parts of tetraethyl pyrophosphite in 120 parts of trichlorotrifluoroethane

2) Solution of 3 »65 parts of tert-butyl perpivalate in 40 parts of trichlorotrifluoroethane

3) Mixture of 50 parts of tetrafluoroethylene and 15 parts Hexafluoropropylene.

In addition, the reaction ^{temperature is kept at 60 °} C. for 2 hours and then at 80 ^° C. for a further 2 hours.

(B) A slurry of the following components is purged with air for 2 hours:

Distilled water Sodium chloride Asbestos

(same type as in example 1)

A dispersion of the following ingredients is then added to the slurry:

1) Dispersion of 4 * 54 parts of the part of (A) in 50 parts of methanol

2) Powdered tetrafluoroethylene / hexafluoropropylene (85:15) copolymer 1.90 parts,

The slurry is purged with air for 2 hours and then in a mixer for 1 minute on medium speed mixed.

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2420 2 Parts 263 Parts 24, Parts

The slurry is then made according to the example 3 (B) made a mat.

(C) The mat produced according to (B) is in the diaphragm position applied to the cathode of a chlor-alkali cell. When operating the cell are to achieve the The following current densities require the following mean voltages:

YoIt

2.86 0.129

3 »04 0.182

3.10 0.204

Such results are also achieved if the diaphragm is placed directly on the cathode using analogous methods generated.

End of description

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... .i.: i! t}. ' Mü. :: hc-i SG. Γ. . . ·. ":,; I 28

March 2, 1977 ΪΡ 6080 A

EGG. PU PONT SE HEMOUES AND COMPANY Wilmington, Delaware »V.St.A.

Phosphonated fluorotelomers

709836/0921

Claims (2)

BI. DU PONT DB HEMOUHS AND COMPANY 27 0909 7 FP 6ΟΘΟ A PATENT CLAIMS 1. Fluorotelomers made from polymeric fluorocarbons with phosphorus-containing end groups »characterized by the general formulas 0 0 η η Y ₁ 0-P-OY fc% P. OY ₂ OY, or / OvO ° / 0v Z ₁ P (X) = P Z ₀ \ q ^ ^x 0 ^ in which Y ₁ »Y ₂ * Y * and Y. are identical or different and each represent an alkyl radical having 1 to 10 carbon atoms, an alkyl radical having 1 to 10 carbon atoms substituted by at least one alkyl radical having 1 to 4 carbon atoms or a monovalent metal
Z is a homo- or cotelomeric portion - 1 709836/0921 ORIGINAL INSPECTED ET 6080 A (a) one or more monoethylenically unsaturated Monomers »that (which) are fully composed of fluorine atoms or a combination of at least one fluorine atom and chlorine or Bromine atoms is (are) substituted »and / or (b) a perfluoroalkyl vinyl ether whose alkyl radical 1 has up to 10 carbon atoms » represents » Z ₁ and Z ₂ »which are identical or different and each represent a divalent metal» an alkylene radical having 1 to carbon atoms or an alkylene radical having 1 to 10 carbon atoms substituted by at least one alkyl radical having 1 to 4 carbon atoms »where Z _{2 is} also derived from T ₁ and T _{2 can} consist »and η has a value from 2 to 500, as well as the salts of these fluorotelomers with one or more trivalent metal (s). 2. Compositions useful in the manufacture of a Diaphragms for an electrolytic cell containing a cell fluid »characterized» in that they (a) 10 to 90 parts by weight, based on the total of (a) and (b), at least one telomer according to claim 1" (b) 10 to 90% by weight based on the total of (a) and (b), a fluoropolymer binder, where (a) plus (b) 10 to 90 weight percent of the total of (a)> (b) and (c) make up » (c) 10 to 90 wt .-% »based on the total of (a), (b) and (c), a fiber material resistant to attack by the cell fluid as (d) a liquid carrier contain. 709836/0921 FF 6080 A 3 * Process for the production of the fluorotelomers according to claim 1 »characterized» that one (a) one or more monoethylenically unsaturated Monomer (s) that (s) are fully composed of fluorine atoms or a combination of at least one fluorine atom and chlorine or bromine atoms is (are) substituted, and / or (b) a perfluoroalkyl vinyl ether »whose alkyl radical has 1 to 10 carbon atoms» brings into contact with a compound under suitable reaction conditions which leads to the formation of a free radical of the general formula T ₁ OP *
• t OY ₂ in which Y ₁ and Y _{2 are} identical or different and each represent an alkyl radical having 1 to 10 carbon atoms or an alkyl radical having 1 to 10 carbon atoms substituted by at least one alkyl radical having 1 to 4 carbon atoms. 709836/0921