JPH0873689A - Production of perfluorocopolymer composition - Google Patents

Abstract

PURPOSE: To obtain a composition having excellent surface smoothness and stress crack resistance of molded article by copolymerizing tetrafluoroethylene with a perfluoro (alkyl vinyl ether) in a dispersion medium of a perfluoropolymer. CONSTITUTION: Tetrafluoroethylene and perfluoro (alkyl vinyl ether) are copolymerized with a perfluoro (alkyl vinyl ether) in a medium such as methanol in which a perfluoropolymer is dispersed and which has >=0.1mm<3> /second volume flow velocity to give the tetrafluoroethylene/a perfluoro (alkyl vinyl ether) copolymer having a higher content of a polymerization unit based on the perfluoro (alkyl vinyl ether) than that of the component of the perfluoropolymer which is tetrafluoroethylene/perfluoro copolymer and/or tetrafluoroethylene polymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a perfluoro copolymer composition, more specifically, it has excellent surface smoothness,
The present invention also relates to a method for producing a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition which gives a molded product excellent in stress crack resistance.

[0002]

2. Description of the Related Art Recently, a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer (hereinafter referred to as P
FA) is a polymer material that has excellent heat resistance, chemical resistance, solvent resistance, etc., and is thermoplastic and easily moldable. It is used in various applications such as parts of semiconductor manufacturing equipment such as required fluid transportation tubes, materials for inner surface coating of containers, and wire coating materials.

[0003] PFA is a crystalline resin, and when it is cooled and solidified after melt molding, PFA is recrystallized to generate a large number of crystal nuclei in the melt, and crystals grow in the same direction around the crystal nuclei. However, the growth stops when the crystals come into contact with each other, and so-called spherulites are generated. PFA
It is known that the surface smoothness of the molded product depends on the size of the spherulites.

In conventional PFA, spherulites generally grow large, and as a result, many irregularities occur on the surface of the molded body. In the tube formed from such PFA, a turbulent flow is generated in the fluid flowing along the inner peripheral surface, and the transport resistance at this time hinders the smooth transport of the fluid. In such a PFA tube, when the flow velocity is low, a portion where no flow occurs on the surface irregularity portion occurs, and the fluid stays in that portion for a long time. Therefore, when ultrapure water is passed through such a PFA tube, there is a problem that bacteria etc. are generated in the portion and the cleanliness of the fluid is impaired. Also,
When it is used as a coating material for the inner surface of a container, a film in which large spherulites are formed is liable to cause stress cracks, resulting in a decrease in durability.

It is known that the size of spherulites depends on the cooling rate after melt-forming, and fine spherulites are formed as the material is rapidly cooled, but rapid cooling may not be possible depending on the molding method. For example, when a thick-walled tube is obtained by an extrusion molding method, if the extruded tube is cooled from the outer surface, the inner surface of the pipe is not rapidly cooled, so that large spherulites are formed and the inner surface of the tube is inferior in smoothness.

Japanese Unexamined Patent Publication No. 48-22183 and Japanese Unexamined Patent Publication No.
JP-A-216548 proposes a method for improving the crystallization characteristics of polyvinylidene fluoride.

The former is a method in which a fluorine-based monomer which produces a polymer having a higher crystallization temperature than that of polyvinylidene fluoride is added to a system in which particles of polyvinylidene fluoride are present, and then the polymerization is carried out. There is a drawback that the physical properties of itself are deteriorated. Further, the former method may not have the effect of improving the crystallization characteristics.

The latter method is a method in which vinylidene fluoride is copolymerized with a small amount of another fluorine-based monomer and has an appropriate molecular weight distribution. This method is essentially the same as polyvinylidene fluoride itself. Relates to different copolymers.

[0009]

SUMMARY OF THE INVENTION The present invention provides a method for producing a PFA composition having crystallization characteristics with a small spherulite size without impairing the excellent physical properties and molding processability of PFA itself. The present invention also provides a PFA composition having crystallization properties that facilitates the formation of fine spherulites even at relatively slow cooling rates. Furthermore, the present invention provides a PFA composition which can give a molded article having excellent surface smoothness and stress crack resistance.

[0010]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that by containing a specific perfluoropolymer in PFA, PF
It was found that the spherulite size in the PFA molded body can be reduced and the surface of the molded body becomes smooth while maintaining the original physical properties and molding processability. And such PFA
It has been found that the composition can be produced smoothly and advantageously by copolymerizing tetrafluoroethylene and perfluoro (alkyl vinyl ether) in a medium in which a specific perfluoropolymer is dispersed.

That is, the present invention is at least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer (A) and a tetrafluoroethylene polymer (B), and a volume flow rate (X ) Is 0.1 mm ³ / sec or more, tetrafluoroethylene and perfluoro (alkyl vinyl ether) are copolymerized in a medium in which a perfluoro polymer is dispersed. ), A tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer (C) having a large content of polymerized units is formed, thereby comprising a mixture of the perfluoropolymer and the resulting copolymer (C). Tetrafluoroethylene / perfluoro characterized by obtaining a composition To provide a manufacturing method of alkyl vinyl ether) copolymer composition.

However, the volumetric flow rate (X) was measured by using a Koka type flow tester at a temperature of 380 ° C. and a load of 25 kg / c.
In m ² , the copolymer (A) and / or the polymer (B) is melted and flown out from a nozzle having a diameter of 2 mm and a length of 8 mm,
It is the volume (mm ³ ) of the copolymer (A) and / or the polymer (B) flowing out in a unit time (second).

In the present invention, the copolymer (C) produced by the copolymerization reaction in a specific medium has a higher content of polymer units based on perfluoro (alkyl vinyl ether) than the copolymer (A). Ethylene / perfluoro (alkyl vinyl ether) copolymer, usually perfluoro (alkyl vinyl ether)
It is preferable that the content of the polymerized units based on (1) is 1.0 to 3.0 mol% and the volume flow rate (Y) is 0.5 to 100 mm ³ / sec.

However, the volumetric flow rate (Y) was measured using a Koka type flow tester at a temperature of 380 ° C. and a load of 7 kg / cm.
² is the volume (mm ³ ) of the copolymer (C) that is melted and flown out from a nozzle having a diameter of 2 mm and a length of 8 mm and flows out in a unit time (second).

If the volumetric flow rate (Y) is too low, the molding processability is insufficient, and if it is too high, the strength decreases. The more preferable copolymer (C) has a volume flow rate (Y) of 1 to 50 mm.
It is a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer that is ³ / sec.

Further, the copolymer (A) and / or the polymer (B) is used as the perfluoropolymer.
The copolymer (A) is a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer having a smaller content of polymer units based on perfluoro (alkyl vinyl ether) than the copolymer (C). B) is a polymer of tetrafluoroethylene alone. The volumetric flow rate (X) of these perfluoropolymers was 0.1 mm ³
/ Sec or more. The volume flow rate (X) of the copolymer (A) or the polymer (B) is preferably 0.1 to ³⁰ mm ³ / sec.

The perfluoropolymer may be a mixture of two or more kinds of copolymers (A) or a mixture of two or more kinds of polymers (B), and further, the copolymer (A) and the polymer (B). )
May be a mixture of. In the case of adopting such a mixture as a perfluoro polymer, volume flow rate of the mixture (X) is a 0.1 mm ³ / sec or more, volume flow rate of the mixture (X) is 0.1 to 30 mm ³ / Seconds are preferred.

If the volume flow rate (X) is too high, the copolymer (A) and / or the polymer (B) is completely melt-mixed with the copolymer (C), so that crystal nuclei are less likely to be formed. As a result, the effect of reducing the spherulite size is reduced. On the other hand, if the volume flow rate (X) is too low, melt mixing with the copolymer (C) becomes difficult. The more preferable copolymer (A) and / or polymer (B) is a perfluoropolymer having a volume flow rate (X) of 0.2 to 10 mm ³ / sec.

Incidentally, a usual tetrafluoroethylene polymer or a copolymer having a small content of polymerized units based on perfluoro (alkyl vinyl ether) has an extremely small volumetric flow rate and is crystallized as a PFA composition in the present invention. The effect of improving the characteristics is not recognized.

The PFA composition preferably has a volume flow rate (Z) of 0.5 to 100 mm ³ / sec. If the volume flow rate is too low, the molding processability is insufficient, and if it is too high, the strength decreases. A more preferred PFA composition is a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition having a volume flow rate (Z) of 1 to 50 mm ³ / sec.

However, the volumetric flow rate (Z) was measured using a Koka type flow tester at a temperature of 380 ° C. and a load of 7 kg / cm.
² , the tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition is melted and flown out from a nozzle having a diameter of 2 mm and a length of 8 mm, and the tetrafluoroethylene / perfluoro (alkyl vinyl ether) flows out in a unit time (second). ) Volume of copolymer composition (mm ³ )
Is.

The melting temperature of the copolymer (C) is 3 in the range of the volume flow rate (X) or (Y) in the present invention.
The melting temperature of the copolymer (A) is about 308 to 332 ° C, and the melting temperature of the polymer (B) is about 3 to 300 ° C.
It is about 23 to 333 ° C. Generally, when the content of polymerized units based on perfluoro (alkyl vinyl ether) is decreased, the melting temperature is increased and the melt moldability is deteriorated.

Therefore, in the PFA composition of the present invention, the amount of the copolymer (A) and / or the polymer (B) contained is 100 parts by weight of the copolymer (C),
It is selected from the range of 0.05 to 20 parts by weight. Per 100 parts by weight of the copolymer (C), the copolymer (A) and /
Alternatively, it is particularly preferable to contain about 0.5 to 10 parts by weight of the polymer (B). When the content of the copolymer (A) and / or the polymer (B) is too small, the effect of reducing the spherulite size is small, while when it is too large, the moldability of the PFA composition is impaired.

Perfluoro (alkyl vinyl ether) which is a copolymerization component in the copolymer (C) or the copolymer (A) has a general formula CF ₂ ═CFO (CF ₂ ) _n CF ₃
Is preferable, since the copolymer (C) or the copolymer (A) has excellent mechanical strength at high temperature,
More preferably, n is an integer of 0-6. Particularly preferred is perfluoro (propyl vinyl ether) where n is 2.

The content of polymerized units based on perfluoro (alkyl vinyl ether) in the copolymer (C) is 1.0 as described above from the viewpoint of moldability of the copolymer.
It is preferably about 3.0 mol%.

The content of polymer units based on perfluoro (alkyl vinyl ether) in the copolymer (A) is preferably 0.3 mol% or less, more preferably 0.2 mol% or less. When the content of the polymerized units based on perfluoro (alkyl vinyl ether) in the copolymer (A) is too large, the generation of crystal nuclei is not sufficient and the effect of reducing the spherulite size becomes small.

The content of polymerized units based on perfluoro (alkyl vinyl ether) in the PFA composition is
From the viewpoint of moldability as a PFA composition, 0.9-3.
It is preferably about 3 mol%.

In the present invention, in a medium in which the copolymer (A) and / or the polymer (B) are dispersed, tetrafluoroethylene and perfluoro (alkyl vinyl ether) are copolymerized to obtain a copolymer ( C) may be produced, or the copolymer (A) may be previously prepared by a polymerization reaction in a medium.
After synthesizing a perfluoropolymer composed of the polymer (B) and / or the polymer (B), the copolymer (C) may be subsequently produced in a medium in which the perfluoropolymer is dispersed.

In the former production method, the perfluoropolymer (copolymer (A) and / or polymer (B)) in the medium is swollen and dispersed by the medium, and the tetrafluoropolymer is dispersed in the medium. By copolymerizing ethylene and perfluoro (alkyl vinyl ether), a PFA composition composed of a mixture of the resulting copolymer (C) and a perfluoropolymer can be obtained. The copolymer (A) and / or polymer (B) used is preferably composed of particles having a particle size of 100 μm or less, and particularly preferably 30 μm or less in order to obtain good dispersion in the medium. If the particle size of the perfluoropolymer is too large, spots due to aggregates of the perfluoropolymer particles are likely to occur on the surface of the molded product from the PFA composition, which is disadvantageous from the viewpoint of the surface smoothness of the molded product. .

Since the copolymer (A) and / or the polymer (B) are inactive, they do not affect the copolymerization reaction of tetrafluoroethylene and perfluoro (alkyl vinyl ether).

The latter manufacturing method is as follows. Generally, the composition based on the monomer unit of the copolymer in radical polymerization is determined by the concentration ratio of the monomer in the polymerization field. In this case, the composition ratio derived from the monomers of the produced copolymer is different from the ratio of the monomers present in the reactor because it depends on the reactivity ratio between the respective monomers.

Therefore, in the latter production method, first, the ratio of tetrafluoroethylene monomer / perfluoro (alkyl vinyl ether) monomer present in the reactor at the beginning of the polymerization reaction process is changed to perfluoro (alkyl). The content of polymerized units based on vinyl ether) is 0.
3 mol% or less, particularly preferably 0.2 mol% or less, set so as to synthesize a copolymer (A), or
The tetrafluoroethylene polymer (B) is synthesized by using the tetrafluoroethylene monomer alone. Next, after producing a predetermined amount of the copolymer (A) or the polymer (B), the reaction is continued to synthesize the copolymer (C). In the latter stage of continuously supplying the monomer consumed by the reaction, the ratio of tetrafluoroethylene monomer / perfluoro (alkyl vinyl ether) monomer is changed to the content of polymerized units based on perfluoro (alkyl vinyl ether). The amount is 1.
It is set to produce a copolymer (C) of 0 to 3.0 mol%.

In the present invention, tetrafluoroethylene and perfluoro (alkyl vinyl ether) in the medium
For the copolymerization reaction, various polymerization methods such as solution polymerization, suspension polymerization and emulsion polymerization can be adopted. In particular, the solution polymerization method and suspension polymerization method are preferably applied.

CF ₂ ClCF ₂ has a small ozone depletion potential and can increase the molecular weight of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer as a polymerization medium in the solution polymerization method or suspension polymerization method. C
It is preferable to use a mixed medium of HClF and water.

In the present invention, a wide range of reaction conditions can be adopted without particular limitation. For example, the polymerization reaction temperature can be selected as an optimum value depending on the type of the polymerization initiation source and the like, and usually about 0 to 100 ° C, particularly about 30 to 90 ° C can be adopted. The reaction pressure can be appropriately selected and is usually 2 to 100 k.
From the viewpoint of reaction rate, it is preferable to employ g / cm ² , especially about 5 to ²⁰ kg / cm ² . In the present invention, the polymerization reaction can be advantageously carried out without requiring an excessive reaction pressure, but it is also possible under reduced pressure conditions.

In the present invention, as chain transfer agents for controlling the molecular weight of the copolymer, hydrocarbons such as hexane, hydrofluorocarbons such as CF ₂ H ₂ , ketones such as acetone, alcohols such as methanol and ethanol are used. , Or mercaptans such as methyl mercaptan, etc., and methanol is preferred from the viewpoints of easy handling and thermal stability of the produced copolymer.

In the present invention, the polymerization initiator can be appropriately selected from those conventionally used. For example,
Organic peroxides such as di (chlorofluoroacyl) peroxide, di (perfluoroacyl) peroxide, t-butylperoxyisobutyrate, diisopropylperoxydicarbonate, azo compounds such as azobisisobutyronitrile, persulfate Inorganic peroxides such as potassium may be mentioned. It is preferable to use di (perfluoroacyl) peroxide from the viewpoint of thermal stability of the produced copolymer.

The amount of the polymerization initiator used can be appropriately set depending on the type, the polymerization reaction conditions and the like, but is usually 0.005 to 5% by weight based on the total amount of the monomers to be subjected to the copolymerization reaction. In particular, about 0.05 to 0.5% by weight can be adopted.

The PFA composition according to the present invention gives a molded product having a spherulite size of 25 μm or less, and an inner surface roughness of 0.
It gives extruded tubes of 5 μm or less. Furthermore, since the PFA composition according to the present invention has a crystallization property that easily produces fine spherulites even at a relatively slow cooling rate, it has excellent inner surface smoothness even when a thick tube is molded by an extrusion molding method. The tube can be obtained smoothly and advantageously.

In the present invention, spherulite size, inner surface roughness,
And the crystallization temperature is defined as follows.

[Spherulite size] Samples at 340 ° C. and thickness of 20
A test film is prepared by compression-molding into a film of 0 μm, and then rapidly cooling to near room temperature in a cooling press machine for 5 minutes. The spherulite size is measured by observing the surface of the test film with a polarizing microscope.

[Crystallization temperature] Scanning differential calorimeter (DS
The exothermic peak when the temperature is lowered at 10 ° C./min is obtained by C), and the temperature at that time is set as the crystallization temperature.

[Inner Surface Roughness] A sample is extruded into a tube having an inner diameter of 8 mm and an outer diameter of 10 mm at 380 ° C. using a short-axis extruder, and then water-cooled from the outside of the tube to prepare a test tube. The inner surface roughness of the test tube is measured with a roughness meter (Surfcoder SE-30H manufactured by Kosaka Laboratory: trade name).

[0044]

In the molded article from the PFA composition of the present invention,
The reason why the spherulite size is reduced and improved is not always clear, but it is considered as follows.

That is, generally, when the content of polymerized units based on perfluoro (alkyl vinyl ether) in PFA decreases, the crystallization temperature increases with the melting temperature of the copolymer. For example, a polymer (B) containing no polymerized units based on perfluoro (alkyl vinyl ether)
Has a crystallization temperature of about 312 to 317 ° C., and the copolymer (A) having a small content of polymer units based on perfluoro (alkyl vinyl ether) has a crystallization temperature of 290.
It is about 310 ° C.

On the other hand, a copolymer (C) having a large content of polymerized units based on perfluoro (alkyl vinyl ether)
Has a crystallization temperature of about 280 ° C., which is lower than that of the copolymer (A) or the polymer (B).

Therefore, in the case of only the copolymer (C), the number of crystal nuclei is small because the crystallization temperature is low and it is difficult to generate crystal nuclei when solidified after melt-molding, and the spherulites centering on the small crystal nuclei. Grows big. On the other hand, P of the present invention
In the case of an FA composition, when solidifying after melt molding, the copolymer (A) or the polymer (B) starts to crystallize at a temperature higher than the crystallization temperature of the copolymer (C). Crystal nuclei are formed.

The larger the number of crystal nuclei, the more the crystals come into contact with the adjacent crystals before the crystals grow larger, and thus the growth stops and the spherulite size becomes smaller. Then, if crystal nuclei other than the copolymer (C) are present, the copolymer (C) is also easily crystallized,
It is considered that the crystallization temperature of the PFA composition of the present invention is higher than that of the copolymer (C).

[0049]

EXAMPLES Examples 1, 2 and 3 are examples, and Example 4 is a comparative example. Note that the PFA generated in Examples 1 to 3
The property value of the copolymer was measured for the PFA copolymer obtained by the copolymerization reaction under the same conditions except that the perfluoropolymer was not produced or was not charged.

Example 1 A stainless steel reactor having an internal volume of 1.1 liter was degassed, and 470 g of water and CF ₂ ClCF _{2 were used.}
290 g of CHClF (hereinafter referred to as R225), perfluoro (propyl vinyl ether) (hereinafter referred to as PPVE
5 g of tetrafluoroethylene (hereinafter referred to as TF)
Charged 80 g (referred to as E) and 19 g of methanol, and 5
Keeping at 0 ° C., 0.5 g of 1% by weight R225 solution of di (perfluorobutyryl) peroxide as a polymerization initiator
Was charged to start the reaction. TF consumed during the reaction
An amount of TFE commensurate with E was continuously introduced into the reactor, and the reaction pressure was maintained at 13.0 kg / cm ² .

When 15 g of TFE was introduced, PPVE
Was added to the reactor. The particle size of the perfluoropolymer produced up to this point was 10 μm or less, which was almost the same as the amount of TFE consumed by the reaction.

While continuously introducing TFE, P
The synthetic reaction of the FA copolymer was continued. 40g TFE
20 g of PPVE was further added at the time of introducing. During the polymerization reaction, a polymerization initiator was continuously added so that the polymerization rate became almost constant. Total TFE 100g, PPVE
40 g in total was introduced to complete the synthesis reaction of the PFA copolymer, and 105 g of a white copolymer composition was obtained as a slurry.

Amount and property value of perfluoropolymer, amount and property value of PFA copolymer, composition of the obtained copolymer composition (perfluoropolymer / PFA copolymer weight ratio) and Table 1 shows the property values and the physical property values of the molded product of the copolymer composition.

[Example 2] A stainless steel reaction vessel having an internal volume of 1.1 liter was degassed, and 470 g of water and 29 of R225 were used.
Charge 0 g, 56 g of TFE, 19 g of methanol,
The temperature was maintained at 50 ° C., and 1 g of a 0.25 wt% R225 solution of di (perfluorobutyryl) peroxide as a polymerization initiator was charged to start the reaction. An amount of TFE commensurate with the TFE consumed during the reaction was continuously introduced into the reactor,
The reaction pressure was maintained at 10.0 kg / cm ² .

When 5 g of TFE was introduced, 25 g of PPVE was added to the reactor. The particle size of the perfluoropolymer produced up to this point was 10 μm or less, which was almost the same as the amount of TFE consumed by the reaction.

While continuously introducing TFE, P
The synthetic reaction of the FA copolymer was continued. During the polymerization reaction, a polymerization initiator was continuously added so that the polymerization rate became almost constant. A total of 100 g of TFE was introduced to complete the synthesis reaction of the PFA copolymer, and 106 g of a white copolymer composition was obtained as a slurry.

Amount and property value of perfluoropolymer, amount and property value of PFA copolymer, composition of the obtained copolymer composition (weight ratio of perfluoropolymer / PFA copolymer) and Table 1 shows the property values and the physical property values of the molded product of the copolymer composition.

Example 3 A stainless steel reaction vessel having an internal volume of 1.1 liter was degassed, and 470 g of water and 29 of R225 were used.
0 g, 56 g of TFE, 25 g of PPVE, a volume flow rate (X) of 1.3 mm ³ / sec, a perfluoropolymer of 5 g of a tetrafluoroethylene polymer having a particle diameter of 30 μm or less, and 19 g of methanol were charged at 50 ° C. And 1 g of a 0.25 wt% R225 solution of di (perfluorobutyryl) peroxide as a polymerization initiator was charged,
The reaction was started. An amount of TFE commensurate with the TFE consumed during the reaction was continuously introduced into the reactor and the reaction pressure was adjusted to 1
It was maintained at 0.0 kg / cm ² . During the polymerization reaction, a polymerization initiator was continuously added so that the polymerization rate became almost constant.

When the amount of TFE introduced reached 100 g, the PFA copolymer synthesis reaction was terminated, and 112 g of a white copolymer composition was obtained as a slurry.

Charge amount and property value of perfluoropolymer, production amount and property value of PFA copolymer, composition of the obtained copolymer composition (perfluoropolymer / PFA copolymer weight ratio) and Table 1 shows the property values and the physical property values of the molded product of the copolymer composition.

Example 4 PPVE was used only at the start of polymerization.
TFE was introduced into the reactor in the same manner as in Example 1 except that the reaction mixture was charged and the post-addition was not performed during the polymerization reaction, the reaction pressure was kept constant, and 100 g of TFE was added after the completion of the polymerization. The amount of PFA copolymer produced was 104 g. PF obtained
Table 1 shows the production amount and property value of the A copolymer, and the physical property value of the molded product of the PFA copolymer.

[0062]

[Table 1]

[0063]

According to the production method of the present invention, a PFA composition in which powdery particles of a specific perfluoropolymer are uniformly dispersed in PFA can be produced smoothly and advantageously. PFA obtained
The composition maintains the physical properties and molding processability of PFA, and
A molded product having fine spherulites and excellent surface smoothness can be provided.

Claims (11)

[Claims] 1. At least one selected from the group consisting of a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer (A) and a tetrafluoroethylene polymer (B) and having a volume flow rate (X) of 0. .1
Polymerization based on perfluoro (alkyl vinyl ether) from copolymer (A) by copolymerizing tetrafluoroethylene and perfluoro (alkyl vinyl ether) in a medium in which a perfluoro polymer having a rate of mm ³ / sec or more is dispersed. By producing a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer (C) having a large content of units, a composition comprising a mixture of the perfluoropolymer and the resulting copolymer (C) is obtained. A method for producing a tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition, comprising: However, the volumetric flow rate (X) was measured using a Koka type flow tester at a temperature of 380 ° C. and a load of 25 kg / cm ^2.
Then, the copolymer (A) and / or the polymer (B) is melted and flown out from a nozzle having a diameter of 2 mm and a length of 8 mm and flows out in a unit time (second). It is the capacity (mm ³ ) of (B). 2. The copolymer (C) produced has a content of polymerized units based on perfluoro (alkyl vinyl ether) of 1.0 to 3.0 mol%, and a volume flow rate (Y) of 0.1. The manufacturing method according to claim 1, which is 5 to 100 mm ³ / sec.
However, the volumetric flow rate (Y) was ² at a temperature of 380 ° C., a load of 7 kg / cm ² , and a diameter of 2
This is the volume (mm ³ ) of the copolymer (C) which is melted and flown out from a nozzle having a length of 8 mm and a length of 8 mm and flows out in a unit time (second). 3. The method according to claim 1, wherein 100 parts by weight of the copolymer (C) is produced with respect to 0.05 to 20 parts by weight of the perfluoropolymer. 4. The copolymer (A) has a content of polymerized units based on perfluoro (alkyl vinyl ether) of 0.3.
Mol% or less, and volume flow rate (X) is 0.1 to 30
The manufacturing method according to claim 1, wherein the manufacturing method is mm ³ / sec. 5. The polymer (B) has a volume flow rate (X) of 0.1.
The production method according to any one of claims 1 to 4, which is a tetrafluoroethylene polymer having a rate of -30 mm ³ / sec. 6. The perfluoropolymer has a particle size of 100 μm.
It is the following, The manufacturing method in any one of Claims 1-5. 7. The perfluoropolymer is obtained by polymerizing tetrafluoroethylene and / or copolymerizing tetrafluoroethylene and perfluoro (alkyl vinyl ether) in a medium. Production method. 8. The tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition has a content of polymer units based on perfluoro (alkyl vinyl ether) of 0.9 to 3.3 mol%, and a capacity. The flow velocity (Z) is 0.5 to 100 mm ³ / sec.
One of the manufacturing method of. However, the volume flow rate (Z) was measured using a Koka type flow tester at a temperature of 380 ° C. and a load of 7
A tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition is melted and flown out from a nozzle having a diameter of 2 mm and a length of 8 mm at kg / cm ² , and tetrafluoroethylene / perfluoro flows out in a unit time (second). It is the volume (mm ³ ) of the (alkyl vinyl ether) copolymer composition. 9. Perfluoro (alkyl vinyl ether)
Is perfluoro (propyl vinyl ether), The manufacturing method in any one of Claims 1-8. 10. The method according to claim 1, wherein the tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition gives a molded product having a spherulite size of 25 μm or less. 11. The method according to claim 1, wherein the tetrafluoroethylene / perfluoro (alkyl vinyl ether) copolymer composition gives an extruded tube having an inner surface roughness of 0.5 μm or less.