JPS6244570B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a non-aqueous dispersion of an acid-type fluorinated polymer, and more specifically, a method for making an aqueous medium hydrophilic without destroying the dispersion state of the aqueous dispersion obtained by copolymerization in an aqueous medium. The present invention relates to a new manufacturing method capable of obtaining a highly concentrated non-aqueous dispersion by substituting an organic solvent. Conventionally, since fluorinated polymers generally have resistance to organic solvents, organic solvent solutions of such fluorinated polymers are hardly known.
In particular, no organic solvent is known that can satisfactorily dissolve fluorinated polymers in which a large number of fluorine atoms are bonded to the main chain carbon atoms. On the other hand, if a solution of the fluorinated polymer as described above can be obtained, various avenues for commercial use will be expanded.
For example, copolymers of fluorinated olefins such as tetrafluoroethylene and fluorinated monomers having sulfonic acid type side chains are cation exchangers with excellent oxidation resistance, chlorine resistance, alkali resistance, and heat resistance. Recently, attention has been paid to its use as a resin body in electrolysis membranes for producing alkali hydroxide and chlorine, fuel cell membranes, general dialysis membranes, and many other uses. If such an organic solvent solution of an acid-type fluorinated polymer can be obtained, the means and operations for forming a film will be extremely easy, and it will be possible to manufacture membranes of arbitrary complex shapes and extremely thin membranes. Various advantages are brought about by making the solution into a solution, such as facilitating the production of diaphragms by impregnation, and also making it possible to repair pinholes in diaphragms and appropriately coat the surfaces of objects with fluorinated polymers. In the case of fluorinated polymers having highly polar and strongly acidic groups such as sulfonic acid,
It is known that only when the sulfonic acid group is in a specific form such as acid, sulfonamide or sulfonate is it soluble in highly polar organic solvents, as seen in Japanese Patent No. 13333. The present applicant previously filed two patent applications regarding organic solvent solutions of carboxylic acid type fluorinated polymers. That is, a fluorinated polymer having a carboxylic acid side chain as -COOQ (Q is an alkali metal, etc.) described in JP-A-54-107949 is dissolved in a highly polar organic solvent such as alcohol or glycol. or the fluorinated polymer having a pendant side chain containing a carboxylic acid ester group as described in Japanese Patent Application No. 54-56912 is a fluorinated organic solvent such as trichlorotrifluoroethane or benzotrifluoride. It is a solution dissolved in According to the research conducted by the present inventors, it is difficult to increase the concentration of the fluorinated polymer in the organic solvent solution as described above, and a solution having a concentration of about 5% by weight is usually obtained. Considering film formation from such a solution, it is natural that it is desirable to increase the concentration of the fluorinated polymer as much as possible. As a result of various studies aimed at creating a highly concentrated solution, the inventors of the present invention have come to the following extremely interesting findings. That is, an acid type fluorinated polymer having an acid type functional group such as a sulfonic acid group or a phosphonic acid group can be produced as a highly concentrated aqueous dispersion by emulsion polymerization in an aqueous medium.
It is possible to replace the aqueous medium of such aqueous dispersions with a hydrophilic organic solvent such as an alcohol. Although the reason is not necessarily clear, the dispersion state is not destroyed even when replaced with a hydrophilic organic solvent, and a non-aqueous dispersion liquid that maintains a stable dispersion state can be obtained. Furthermore, the non-aqueous dispersion thus obtained can be applied to film production, etc., in the same way as an organic solvent solution. For example, an aqueous latex of a sulfonic acid type fluorinated polymer can be separated into an aqueous medium layer and a latex layer with increased polymer concentration by a suitable centrifugation operation, and a hydrophilic organic solvent is added to such a concentrated latex layer. In addition, repeated centrifugation operations reduce the aqueous medium content in the concentrated latex layer and achieve replacement by hydrophilic organic solvents. The sulfonic acid type fluorinated polymer is dispersed in the hydrophilic organic solvent while maintaining the dispersion state of the aqueous latex. By such substitution treatment, a non-aqueous dispersion can be obtained which maintains a polymer concentration similar to that in the aqueous latex. Thus, the present invention has been completed based on the above findings, and consists of a fluorinated ethylenically unsaturated monomer and an acid type functional group (provided that a carboxylic acid group or a functional group convertible to a carboxylic acid group) is used. An acid type fluorinated polymer having a functional monomer content of 5 to 40 mol % is obtained by copolymerizing a functional monomer having a polymerizable functional monomer having a polymerizable functional monomer (excluding the above) in an aqueous medium by the action of a polymerization initiation source. An acid-type fluorinated polymer, which is characterized by obtaining an aqueous dispersion containing in a dispersed state, and replacing the aqueous medium of the aqueous dispersion with a hydrophilic organic solvent without destroying the dispersion state of the aqueous dispersion. The present invention provides a new method for producing a non-aqueous dispersion of coalescence. According to the present invention, a non-aqueous dispersion with a high concentration of about 50% by weight can be easily obtained using a wide variety of hydrophilic organic solvents, and the mechanical or chemical stability of the dispersion is Very good. The viscosity of the dispersion can be freely adjusted depending on the purpose and use by selecting the type of solvent used. By casting the non-aqueous dispersion, a good copolymer film free from defects such as pinholes can be obtained. In the present invention, it is important to use a polymerizable monomer containing a sulfonic acid group, a phosphonic acid group, or an acid type functional group convertible to these groups as the functional monomer. In consideration of the chlorine resistance, oxidation resistance, etc. of the resulting polymer, such acid-type functional monomer () is usually desirably a fluorovinyl compound. CF ₂ =CX−(CFX′) _p −(OCF ₂ CFY) _l −(O) _n −
A fluorovinyl compound represented by (CFY') _o -A is exemplified. Here, p is 0 to 1, l is 0 to
3, m is an integer from 0 to 1, n is an integer from 0 to 12, X is a fluorine atom, a chlorine atom, or -CF ₃ , X' is a fluorine atom or -CF ₃ , and Y is a fluorine atom atom or _-CF3 , and Y' is a fluorine atom or a carbon number of 1 to 10
perfluoroalkyl group. Also, A is −SO ₂ F, −SO ₃ M, −SO ₃ H,

【formula】

【formula】

It is an acid type functional group such as [Formula], R ¹ is an alkyl group having 1 to 10 carbon atoms, and M is an alkali metal or a quaternary ammonium group. From the viewpoint of performance and availability, X is a fluorine atom, Y is -CF ₃ , Y' is a fluorine atom, p is 0, l
is 0 to 1, m is 0 to 1, and n is 0 to 8, and A is -SO ₂ F or

[Formula] and R is preferably a lower alkyl group. Preferred representative examples of such fluorovinyl compounds include CF ₂ = CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ SO ₂ F,
CF ₂ = CFSO ₂ F, CF ₂ = CFCF ₂ OCF ₂ CF ₂ SO ₂ F, etc. Next, examples of the fluorinated ethylenically unsaturated monomer () include ethylene tetrafluoride, ethylene trifluoride chloride, propylene hexafluoride, ethylene trifluoride, vinylidene fluoride, and vinyl fluoride. , preferably the general formula CF ₂ =CZZ′ (where Z, Z′ are fluorine atom, chlorine atom, hydrogen atom, or −CF ₃ )
It is a fluorinated olefin compound represented by
Among these, perfluoroolefin compounds are preferred, and tetrafluoroethylene is particularly preferred. In the present invention, each of the functional monomers () and ethylenically unsaturated monomers () may be used in combinations of two or more, and in addition to these compounds, other monomer compounds may also be used. components, such as olefin compounds () represented by the general formula CH ₂ =CR ₄ R ₅ (where R ₄ and R ₅ represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aromatic nucleus), CF ₂
= Fluorovinyl ether such as CFOR _f (R _f represents a perfluoroalkyl group having 1 to 10 carbon atoms), CF ₂ =CF−CF=CF ₂ , CF ₂ =CFO
( _CF2 ) _1~4 OCF=Divinyl monomer such as _CF2 ,
Furthermore, one or more types of other functional monomers such as carboxylic acid type functional groups can also be used in combination. Preferred representative examples of the olefin compound () include ethylene, propylene, butene-1, isobutylene, styrene, α-methylstyrene, pentene-1, hexene-1, heptene-1,3-methyl-butene-1,4-methyl -Pentene-1, etc. Among them, ethylene, propylene, isobutylene, etc. are particularly preferred from the viewpoint of production and performance of the resulting copolymer. In addition, for example, by using a divinyl monomer in combination, the resulting copolymer can be crosslinked to improve the mechanical strength of molded products such as films and membranes. In the acid-type fluorinated polymer of the present invention, the composition ratios of the functional monomer (), the fluorinated olefin compound (), and the olefin compound () and other components are primarily fluorinated. It is related to the performance of the chemical polymer, for example, when used as an ion exchange membrane for electrolytic cells, and it is also related to the stability of the dispersion state during substitution treatment from an aqueous dispersion to a non-aqueous dispersion with a hydrophilic organic solvent. It is important because First, the amount of the functional monomer () is directly related to the ion exchange capacity and also to the stability of the dispersion state, but it is 5 to 40 mol%, especially 10 to 30 mol% in the copolymer.
degree is suitable. If the amount of the functional monomer () present is too large, the mechanical strength of the ion exchange membrane will be impaired, and furthermore, the ion exchange performance will decrease due to an increase in water content. In addition to not exhibiting an ion exchange function, this is not preferable because it impairs the stability of maintaining the dispersed state during substitution treatment. In the present invention, the reason why the presence of acid type side chains in the fluorinated polymer is related to the stability of the dispersion state is not necessarily clear. However, in centrifugation treatment of aqueous dispersions, acid-type fluorinated polymers having acid-type functional groups such as sulfonic acid groups maintain a stable dispersion state in the concentrated latex layer, whereas sulfonic acid Since latex destruction is observed in fluorinated polymers that do not have functional groups such as groups at the same concentration, it is thought that the acid type side chains make some contribution to the stability of the dispersion state. It will be done. It goes without saying that such explanations are provided to assist in understanding the present invention and do not limit the present invention in any way. Therefore, the remainder of the compound () in the copolymer of the present invention is occupied by the () and other compounds (),
The amount of the olefin compound in parentheses () is important because it greatly affects the electrical, mechanical properties, chlorine resistance, etc. when used as an ion exchange membrane. Therefore, when the olefin compound () is used in combination, the molar ratio of the olefin compound ()/fluorinated olefin compound () is preferably from 5/95 to
A ratio of 70/30, particularly 10/90 to 60/40 is preferred. Also, when using fluorovinyl ether or divinyl ether, etc., 30%
It is suitable that the usage ratio is less than mol %, preferably about 2 to 20 mol %. In a preferred embodiment of the invention, the ion exchange capacity is selected from a wide range of 0.5 to 2.2 milliequivalents/gram dry resin, but what is distinctive is that even with increased ion exchange capacity, the resulting copolymer The molecular weight of the copolymer can be increased without deteriorating the mechanical properties or durability of the copolymer. The ion exchange capacity varies depending on the type of copolymer within the above range, but preferably 0.8 milliequivalents/gram dry resin or more, particularly 1.0 milliequivalents/gram dry resin or more, which is suitable for use as an ion exchange membrane. Preferable in terms of mechanical properties and electrochemical performance. In addition, the molecular weight of the acid-type fluorinated polymer in the present invention is important because it is related to the mechanical performance and film formability as an ion exchange membrane, and when expressed as a _TQ value, it is preferably 150°C or higher. The temperature is preferably about 170 to 340°C, particularly about 180 to 300°C. In this specification, the term " _TQ " is defined as follows. That is, _TQ is defined as the temperature at which the volume flow rate is 100 mm ³ /sec, which is related to the molecular weight of the copolymer. Here, the volumetric flow rate is the diameter of the copolymer under a pressure of 30 kg/cm ² at a constant temperature.
mm, let the melt flow out from the orifice with a length of 2 mm,
The amount of copolymer flowing out is shown in units of mm ³ /sec. Incidentally, the "ion exchange capacity" was determined as follows. That is, an H-type cation exchange resin membrane was left in 1N HCl at 60°C for 5 hours to completely remove H.
The mixture was converted into a mold and thoroughly washed with water to ensure that no HCl remained. Then, 0.5g of this H-type film was heated to 0.1N.
It was left standing at room temperature for 2 days in a solution prepared by adding 25 ml of water to 25 ml of NaOH. The membrane is then taken out and the amount of NaOH in the solution is determined by back titration with 0.1N HCl. In the present invention, the copolymerization reaction between the functional monomer and the fluorinated olefin compound is carried out at a weight ratio of 20/1 of the aqueous medium/functional monomer.
It is preferable to control the ratio to below, preferably 10/1 or less. If the amount of aqueous medium used is too large, the copolymerization reaction rate will decrease significantly,
It takes a long time to obtain a high copolymer yield. Also, too much aqueous medium makes it difficult to achieve high molecular weights when high ion exchange capacities are used. Furthermore, the following difficulties are recognized when using a large amount of an aqueous medium. For example, there are disadvantages in operational aspects such as an increase in the size of the reactor and separation and recovery of the copolymer. Next, in the present invention, it is preferable to employ a copolymerization reaction pressure of 7 kg/m ² or more. If the copolymerization reaction pressure is too low, the copolymerization reaction rate cannot be maintained at a level that is practically satisfactory, and there are also difficulties in forming a high molecular weight copolymer. Furthermore, if the copolymerization reaction pressure is too low, the ion exchange capacity of the resulting copolymer will become extremely high, and the mechanical strength and ion exchange performance will tend to decrease due to increased water content. In addition, the copolymerization reaction pressure is desirably selected from 50 kg/cm ² or less, taking into consideration the reaction apparatus or work operation in industrial implementation. Although it is possible to employ copolymerization reaction pressures higher than this range, it may not proportionately improve the objectives of the present invention. Therefore, in the present invention, the copolymerization reaction pressure is set at 7 to 50
Kg/cm ² , preferably selected from the range of 9 to 30 Kg/cm ² is optimal. In the copolymerization reaction of the present invention, conditions and operations other than the above-mentioned reaction conditions are not particularly limited and may be adopted over a wide range. For example, the optimum copolymerization reaction temperature can be selected depending on the type of polymerization initiation source, reaction molar ratio, etc., but normally, too high or too low a temperature is disadvantageous for industrial implementation. ℃, preferably from about 30 to 80℃. Therefore, in the present invention, as a polymerization initiation source,
It is desirable to select one that exhibits high activity at the above-mentioned suitable reaction temperature. For example, it is possible to use ionizing radiation that is highly active even at room temperature or lower, but it is usually more advantageous to use an azo compound or a peroxy compound for industrial implementation. Polymerization initiation sources suitably employed in the present invention include disuccinic acid peroxide, benzoyl peroxide, which exhibits high activity at about 20 to 90°C under the copolymerization reaction conditions,
Diacyl peroxides such as lauroyl peroxide and dipentafluoropropionyl peroxide, 2,2'-azobis(2-amidinopropane) hydrochloride, 4,4'-azobis(4-cyanowallerianic acid), azobisisobutyl Azo compounds such as lonitrile, peroxy esters such as t-butyl peroxy isobutyrate and t-butyl peroxy pivalate, peroxy dicarbonates such as diisopropyl peroxy dicarbonate, di-2-ethylhexyl peroxy dicarbonate, etc. carbonate,
These include hydroperoxides such as diisopropylbenzene hydroperoxide, inorganic peroxides such as potassium persulfate and ammonium persulfate, and their redox systems. In the present invention, the concentration of the polymerization initiator is 0.0001 to 3% by weight, preferably 0.001% by weight based on the total monomers.
It is about 2% by weight. By lowering the initiator concentration, it is possible to increase the molecular weight of the resulting copolymer and maintain a high ion exchange capacity. If the initiator concentration is too high, the tendency to decrease the molecular weight increases, which is disadvantageous to the production of high ion exchange capacity, high molecular weight copolymers. Other surfactants, dispersants, buffers, pH adjusters, etc. used in ordinary aqueous medium polymerization can also be added. In addition, as long as it does not inhibit the copolymerization reaction between the fluorinated olefin compound and the specific functional monomer and has low chain transfer, for example, fluorinated or fluorinated chlorinated solvents known as fluorocarbon solvents can be used. Inert organic solvents such as saturated hydrocarbons can also be added. Therefore, in the copolymerization in an aqueous medium in the present invention, it is preferable to control the concentration of the produced copolymer to 40% by weight or less, preferably 30% by weight or less. If the concentration is too high, problems such as increased stirring load, difficulty in removing heat, and insufficient diffusion of the fluorinated olefin monomer will occur. In the present invention, the aqueous dispersion obtained as described above is subjected to a substitution treatment with a hydrophilic organic solvent. As for the substitution treatment means, various means can be employed as long as they do not destroy the dispersion state of the aqueous dispersion. For example, a combination of separation of the aqueous medium layer by centrifugation and addition of a hydrophilic organic solvent, a combination of separation of the aqueous medium layer by an electric gradient method or freezing method and addition of a hydrophilic organic solvent, or a combination of separation of the aqueous medium layer by centrifugal separation and addition of a hydrophilic organic solvent, or Examples include a method of removing water by evaporation after adding a hydrophilic organic solvent. Usually, it is effective to gradually separate the aqueous medium layer by repeating the steps of separating the aqueous medium layer by centrifugation, adding a hydrophilic organic solvent to the concentrated layer, and subjecting this to centrifugation. can be adopted. Various hydrophilic organic solvents may be used in the substitution treatment in the present invention. Normally,
For the purpose of smoothly and advantageously displacing and separating the aqueous medium, it is desirable to employ a water-soluble organic solvent, and one that dissolves in water at 20° C. in an amount of 0.5% by weight or more is preferable. Specific examples include alcohols, ketones, organic acids, aldehydes, and amines. In addition, hydrophilic organic solvents that are easily compatible with water, such as pyrrolidones, esters, and ethers, may also be used even if their solubility in water is not necessarily high, and a mixed solvent system may also be used. In the operation of adding a hydrophilic organic solvent to the concentrated layer to replace the aqueous medium layer, it is sufficient to repeat the operation depending on the tolerance of water remaining in the non-aqueous dispersion, and usually several times is sufficient. It is. The amount of the organic solvent to be added is not particularly limited, but it is usually 0.5 to 20 parts by weight based on the weight of the polymer. According to the present invention, the concentration of the non-aqueous dispersion can be as high as 60% by weight, but it is usually produced at a concentration of 5% to 50% by weight, preferably 10% to 40% by weight. The viscosity of the non-aqueous dispersion can vary from 10 centipoise to 1,000,000 centipoise depending on the concentration of the dispersion and the type of hydrophilic organic solvent used, but it is suitable for purposes such as obtaining a good copolymer film by casting etc. Usually used in the range of 100 centipoise to 10,000 poise. The non-aqueous dispersion obtained in the present invention can be used in the same manner as an organic solvent solution, and can be used for various purposes and uses. Moreover, since it is possible to achieve a high concentration of about 60% by weight, the range of applications has been expanded and the effectiveness of its use has been excellent. For example, by casting the non-aqueous dispersion or impregnating it into a porous material such as asbestos or polytetrafluoroethylene, and drying and removing the hydrophilic organic solvent, it can be used for electrolysis, dialysis, fuel cells, etc. It is suitable for making films of arbitrary shapes, sheet-like products, etc., and is also suitable for making pinholes in films made in this way or other films for diaphragms, etc.
Extremely effective in repairing damaged areas such as tears. Further, by using the non-aqueous dispersion of the present invention, it becomes extremely convenient to coat the surfaces of objects such as spacer nets and electrodes. Next, embodiments of the present invention will be described in more detail, but it goes without saying that the present invention is not limited by such explanations. Incidentally, parts in the examples are parts by weight unless otherwise specified. Example 1 100 g of ion-exchanged water, 0.2 g of C ₈ F ₁₇ COONH ₄ , and Na ₂ HPO ₄ .
0.5g of 12H ₂ O, 0.3g of NaH ₂ PO ₄・2H ₂ O,
(NH ₄ ) ₂ S ₂ O ₈ was charged at 0.026 g, and then 20 g of CF ₂ =
CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ SO ₂ F was charged. After sufficient degassing with liquid nitrogen, the temperature was raised to 57°C, and 15.0 kg/cm ² of tetrafluoroethylene was introduced to carry out a reaction. During the reaction, tetrafluoroethylene was continuously introduced into the system and the pressure was maintained at 15.0 Kg/cm ² . After 3.5 hours, unreacted tetrafluoroethylene was purged to terminate the reaction. Furthermore, unreacted CF ₂ =
CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ SO ₂ F is extracted and separated by adding trichlorotrifluoroethane.
A stable aqueous dispersion with a concentration of 19% by weight was obtained. CF ₂ in copolymer = CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ SO ₂ F
The composition was 12.1 mol%. The aqueous dispersion was separated into an aqueous medium and a polymer concentrated layer using a centrifuge. The aqueous medium layer was removed, the same amount of water was newly added, and the centrifugation operation was repeated again. The operation was repeated three times to remove the electrolyte used in the polymerization. Next, 15 g of a mixed solvent of N-methylpyrrolidone and methanol (N-methylpyrrolidone/methanol = 2.5/1 weight ratio) was added to the concentrated layer to form a dispersion, and the centrifugation operation was repeated again. Finally, an organic solvent having the above composition was added to the concentrated layer again to produce a non-aqueous dispersion having a copolymer concentration of 20% by weight. The viscosity of the dispersion is
It was 1200 centipoise. The dispersion was cast onto a thoroughly washed glass plate, heated at 50°C for 10 hours, and then heated at 150°C for 5 hours.
A good copolymer film with a thickness of 300μ was obtained by leaving it in an electric furnace for an hour. An ion exchange membrane with an ion exchange capacity of 0.85 meq/g dry resin was obtained by hydrolyzing the film. Example 2 The same operation as in Example 1 was carried out except that the organic solvent used was changed from a mixed solvent of N-methylpyrrolidone and methanol to propanol.
A non-aqueous dispersion having a copolymer concentration of 35% by weight was produced.
The viscosity of the dispersion was 300 centipoise, and a good film was obtained by leaving it on a glass plate at 50°C for 20 hours. Example 3 In Example 1, instead of CF ₂ = CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ SO ₂ F

Polymerization was carried out in the same manner except that [formula] was charged and the reaction was carried out at a polymerization pressure of 14 kg/cm ² .

A 19% by weight aqueous dispersion of a copolymer having the formula: 14.3% by mole was obtained. Desalting the electrolyte from the aqueous dispersion using an ion exchange resin, adding 100 g of diethylene glycol monomethyl ester to the aqueous dispersion,
Water was evaporated using a rotary evaporator.
This operation was repeated three times while adding diethylene glycol monomethyl ester, and finally the diethylene glycol monomethyl ester was concentrated to obtain a stable non-aqueous dispersion having a copolymer concentration of 30% by weight and a viscosity of 420 centipoise.

Claims (1)

[Scope of Claims] 1. A polymerizable functional monomer having a fluorinated ethylenically unsaturated monomer and an acid-type functional group (excluding a carboxylic acid group or a functional group that can be converted to a carboxylic acid group) and copolymerizing the acid type fluorinated polymer in an aqueous medium by the action of a polymerization initiation source to obtain an aqueous dispersion containing the acid type fluorinated polymer having a functional monomer content of 5 to 40 mol% in a dispersed state, A method for producing a non-aqueous dispersion of an acid type fluorinated polymer, which comprises replacing the aqueous medium of the aqueous dispersion with a hydrophilic organic solvent without destroying the dispersion state of the aqueous dispersion. 2 The functional monomer has the general formula CF ₂ =CX−(CFX′) _p
−(OCF ₂ CFY) _l −(O) _n −(CFY′) _o −A (However,
In the formula, p is 0-1, l is 0-3, m is 0-1, n
is an integer from 0 to 12, X is a fluorine atom, a chlorine atom, or _-CF3 , and X' is a fluorine atom or _-CF3
, Y is a fluorine atom or _-CF3 , Y' is a fluorine atom or a perfluoroalkyl group having 1 to 10 carbon atoms, and A is _-SO2F , _-SO3M , -
SO ₃ H, [Formula] [Formula] [Formula] is an acid type functional group, R ¹ is an alkyl group having 1 to 10 carbon atoms, and M is an alkali metal or a quaternary ammonium group) The manufacturing method according to claim 1, which is a fluorovinyl compound represented by: 3 The fluorinated ethylenically unsaturated monomer has the general formula
The production according to claim 1, which is a fluorinated olefin compound represented by CF ₂ =CZZ' (where Z and Z' are a fluorine atom, a chlorine atom, a hydrogen atom, or _-CF3 ) Method. 4 Functional monomer has general formula (However, in the formula, q is 0 to 1, r is 0 to 1, and s is 0
3. The method according to claim 2, wherein the fluorovinyl compound is an integer of 8 to 8, B is -SO ₂ F or [Formula], and R is a lower alkyl group. 5. The manufacturing method according to claim 3, wherein tetrafluoroethylene is used as the fluorinated ethylenically unsaturated monomer. 6. The manufacturing method according to claim 1, which is carried out at a copolymerization reaction temperature of 20 to 90°C. 7. The manufacturing method according to claim 1, which is carried out at a copolymerization reaction pressure of 7 kg/cm ² or more. 8. The production method according to claim 1, wherein the copolymerization reaction is carried out while controlling the concentration of the acid type fluorinated polymer in the produced aqueous dispersion to 40% by weight or less.