JP2002293831A - Fluorine-containing olefin polymer particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition capable of giving a molded article excellent in heat resistance, mechanical strength and transparency or the like. SOLUTION: A fluorine resin particle has a melting point of 230-300 deg.C, an average particle size of 100 nm or less in which the melt process cannot be carried out and a melt flow rate measured at 327 deg.C under a load of 5 kg according to ASTM D3307 of 0.005-0.1 g/10 min. The composition comprises the particle and a fluorine-containing elastomer or a fluorine resin capable of melting process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluororesin particle to be filled in an elastomer or a resin molded product particularly preferably used for sealing parts such as an O-ring and a gasket of a semiconductor manufacturing apparatus. Such a filler imparts cleanness, heat resistance and strength to the obtained sealing material.

[0002]

2. Description of the Related Art Conventionally, it has been practiced to add a fluororesin particle as a filler to a fluorine-containing elastomer to improve the abrasion resistance of a molded article and to lower the friction coefficient. In recent years, such molded articles have been used for sealing parts (O-rings, gaskets, etc.) of semiconductor manufacturing equipment by utilizing the chemical resistance and heat resistance of the fluororesin.

[0003] For example, WO97 / 0823 pamphlet indicates that a composition containing 5 to 50 parts by weight of a fluororesin powder can provide a particularly clean sealant for an etching apparatus of a semiconductor manufacturing apparatus. . Also, in WO95 / 02634 pamphlet,
Fluororesin powder is added in an amount of 2 to 50 per 100 parts by weight of the rubber component.
It is described that a composition blended in parts by weight provides a clean environment as a sealing material for a wet processing device for semiconductors.

[0004] Further, JP-A-2000-239321 and JP-A-2000-239470 disclose that a high-strength is achieved by forming a fluorocarbon rubber and a fluororesin into a nanocomposite (fine dispersion), further improving the engine oil resistance and improving the surface properties. The smoothness is improved.

However, with respect to the heat resistance even when the nanocomposite is formed, the fluororesin melts at a temperature near the melting point of the finely dispersed fluororesin, and there is no merit of forming the nanocomposite. There is a problem that is difficult.

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to fluororesin particles to be filled in a fluorine-containing elastomer or resin,
It is an object of the present invention to provide fluororesin particles capable of imparting good properties to an elastomer vulcanizate even at a temperature exceeding the melting point of the fluororesin particles.

[0007]

That is, the present invention relates to a fluororesin particle having a melting point of 230 to 300 ° C. and an average particle diameter of 100 nm or less which cannot be melt-processed,
The melt flow rate (MFR) measured at 327 ° C. and a load of 5 kg according to D3307 is 0.005 to 0.1 g.
/ 10 min.

As the fluororesin particles, preferred are fluorocopolymers of tetrafluoroethylene (TFE) and a perfluoroolefin other than TFE, particularly fluororesin particles containing at least 90 mol% of TFE units.

The content of perfluoroethylene units other than TFE is preferably from 2 to 9 mol%, and the perfluoroolefin to be copolymerized with TFE is perfluoro (alkyl vinyl ether) (PAVE), especially perfluoro (methyl vinyl ether). Preferred.

[0010] The present invention also relates to an aqueous dispersion of fluororesin particles in which these fluororesin particles are dispersed in water.

The present invention also relates to a fluoroelastomer composition comprising these specific fluororesin particles and a fluoroelastomer, or a fluororesin composition comprising the specific fluororesin particles and a melt-moldable fluororesin.
A perfluoroelastomer is preferable as the fluorine-containing elastomer, and a perfluoro-based resin is preferable as the melt-processable fluororesin.

[0012] The present invention also relates to a sealing part for a semiconductor manufacturing apparatus obtained by molding from these elastomer compositions.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The fluororesin particles of the present invention
It is a crystalline fluororesin particle having a melting point of 0 to 300 ° C., but having a low fluidity even at a temperature higher than the melting point, and having a high molecular weight and cannot be melt processed.

Specifically, the melting point is 230 to 300 ° C., more preferably 250 to 290 ° C., and M at 372 ° C. which is higher than the melting point.
Fluororesin particles having a small FR (hard to flow) having a FR of 0.005 to 0.1 g / 10 min, and more preferably 0.01 to 0.05 g / 10 min are exemplified.

When the melting point is 230 to 300 ° C., the property of heat resistance can be imparted. In addition, since the melt fluidity (MFR) at a high temperature equal to or higher than the melting point is small, it can be used as a filler even at a temperature equal to or higher than the melting point. The characteristics are not significantly impaired.

MFR (372 ° C.) 0.005 g / 10
PTFs smaller than min are homopolymers of TFE
Only E itself exists, causing fibrillation when finely dispersed in the matrix polymer, making fine dispersion extremely difficult. When it is larger than 0.1 g / 10 min, it becomes difficult to impart heat resistance.

As such a fluororesin, a TFE copolymer containing at least 90 mol% of a TFE unit which gives a homopolymer having a relatively low cost, a high reactivity, a high molecular weight and a high crystallinity is most suitable. . The copolymerization component may be any monomer that can be copolymerized with TFE, but a perfluoroolefin other than TFE such as PAVE or hexafluoropropylene (HFP) is preferable from the viewpoint of achieving a high melting point (heat resistance). PAVE, particularly perfluoro (methyl vinyl ether) (PMVE), is preferred because it is relatively inexpensive and has good copolymerizability with TFE. These comonomer units are contained in an amount of 10 mol% or less, particularly 2 to 9 mol% (TFE is 91 to 98 mol%).
Mol%) is preferred. However, the resulting copolymer must be one that cannot be melt processed. When the content of the comonomer unit is reduced, fibrillation occurs during dispersion processing as in the case of PTFE, and fine dispersion becomes difficult. If the amount is too large, the melting point is lowered, so that heat resistance cannot be imparted even when the molecular weight is increased, and the MFR (372 ° C.) increases, so that the resin becomes a melt-processable resin and is not suitable as a heat-resistant filler.

The fluororesin particles for a filler of the present invention are fine particles having an average particle size of 100 nm or less, preferably 20 to 60 nm. By using these fine particles, high strength can be imparted to the molded article. In particular, when an elastomer or resin having excellent transparency is used as the matrix polymer, a transparent molded product can be provided. On the other hand, when the average particle size is large, it becomes difficult to finely disperse the particles in the matrix polymer.

The specific fluororesin particles of the present invention can be produced by a usual emulsion polymerization method, and the resulting polymerization reaction product emulsion can be used as it is or by adjusting the concentration appropriately to obtain an aqueous dispersion. it can. Alternatively, they may be dried once and then re-emulsified and dispersed. Generally, when re-emulsifying, the particle size becomes large.
m.

The present invention also relates to an aqueous dispersion in which the specific fluororesin particles are dispersed in water.

The present invention further relates to a composition comprising a matrix polymer such as a fluorine-containing elastomer or a melt-processable fluororesin, and the specific fluororesin particles as a filler.

The matrix elastomer used in the composition of the present invention may be any elastomer that can form an emulsion in the form of particles and has an affinity for fluororesin particles. In this respect, a fluorine-containing elastomer is preferable.

When a fluoroelastomer is used as the matrix polymer, when the fluororesin particles of the present invention are filled, the characteristics as a filler are not significantly impaired even in kneading or vulcanization at a high temperature.

As the fluorine-containing elastomer, for example, the following formula (1):

[0025]

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Where m / n = 95-50 / 5-5
(Mol%; the same shall apply hereinafter), and R _f is a binary copolymer elastomer (tetrafluoroethylene (TFE) / perfluoro (alkyl vinyl ether) (PAVE) -based elastomer) represented by the following formula: ), Equation (2):

[0027]

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Wherein l / m / n = 95-35 / 0-3
Ternary copolymer elastomer (TFE) represented by 0/5 to 35 and R _f is a perfluoroalkyl group having 1 to 8 carbon atoms)
/ Hexafluoropropylene (HFP) / PAVE elastomer), etc.

[0029]

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Where m / n = 85-60 / 15-4
0) a binary copolymer elastomer represented by the formula (4):

[0031]

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Where l / m / n = 85-20 / 0-4
0/15 to 40), a terpolymer elastomer represented by the formula (5):

[0033]

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(Where l / m / n = 95-45 / 0-1
0/5 to 45, Z ¹ , Z ² and Z ³ are each independently a fluorine atom or a hydrogen atom, and R _f is a perfluoroalkyl group having 1 to 8 carbon atoms), or

[0035]

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(L / m / n = 1 to 80/0 to 80/10
To 50, R _f is the same as described above).

More specifically, a TFE / PAVE copolymer elastomer, vinylidene fluoride (VdF) /
Hexafluoropropylene (HFP) copolymer elastomer, VdF / HFP / TFE copolymer elastomer,
Examples include VdF / TFE / PAVE copolymer elastomers, and these elastomers may further be copolymerized with a small amount of a monomer containing a crosslinkable reactive group.
Examples of the crosslinkable reactive group include an iodine atom, a bromine atom, a nitrile group, a carboxyl group, an unsaturated double bond, a hydroxyl group and the like.

These fluorinated elastomers can be produced by a usual emulsion polymerization method, and the resulting emulsion, which is a polymerization reaction product, can be used as it is or after appropriately adjusting its concentration for co-coagulation described below. it can. Or
Once dried, it may be re-emulsified and dispersed.

Examples of the elastomer other than the fluorine-containing elastomer include hydrogenated nitrile butadiene rubber,
Acrylic rubber, silicone rubber and the like can be mentioned.

The average particle size of the elastomer particles in the emulsion is not particularly limited and is, for example, 10 to 800 nm, preferably 20 to 500 nm. However, if it is smaller than 10 nm, coagulation becomes difficult, and if it is larger than 800 nm, the emulsion becomes unstable and co-coagulation becomes difficult.

The mixing ratio between the fluoroelastomer and the specific fluororesin particles may be appropriately selected depending on the properties to be imparted to the molded article.
1 part by weight or more, preferably 5 parts by weight or more, from the viewpoint of obtaining a reinforcing effect, and 150 parts by weight or less, preferably 100 parts by weight, from the viewpoint of easy rubber processing of the obtained crosslinked product with respect to parts by weight. It is desirable that the content be less than 50 parts by weight.

The combination of the elastomer and the fluororesin particles is determined according to the intended function, taking into account whether or not the coagulation properties are similar or not, and whether or not they have an affinity as a polymer. You just have to choose. Since a copolymer mainly composed of TFE is preferred as the fluororesin particles, the fluorine-containing elastomer is also preferably an elastomer containing TFE. For example, a TFE / PAVE-based elastomer or a TFE / HFP / PAVE-based elastomer obtained by copolymerizing at least one kind of fluoromonomer is used, but not limited thereto.

The elastomer composition of the present invention can be produced by mixing and co-coagulating the above-mentioned emulsion of elastomer particles and the emulsion of fluororesin particles. Co-coagulation can be performed according to a known coagulation method. For example, a method of dropping a mixed solution obtained by mixing an emulsion of elastomer particles and an emulsion of fluororesin particles into a coagulation liquid, or a method of dropping a coagulation liquid into an emulsion mixture can be adopted.

The concentration of the mixed emulsion may be appropriately determined depending on the productivity and the like, and is not particularly limited, but is usually 5 to 50% by weight, preferably 10 to 30% by weight. In coagulation, it is also possible to dilute with pure water 2 to 10 times.

Specific examples of the co-coagulation method include a salting out method, an acid coagulation method, a freeze coagulation method, and a method of coagulating by applying a mechanical shear force.

As the coagulant, for example, acids such as nitric acid, hydrochloric acid, sulfuric acid and the like; metal salts such as aluminum nitrate, aluminum sulfate and the like can be used. Metal salts are preferred from the viewpoint of ease.

The coagulated product obtained by co-coagulation can be used as a base material for molding by washing it if necessary and drying it in a hot air oven or a vacuum dryer.

When the fluoroelastomer composition of the present invention is used as a base material, the resulting molded article can be given excellent heat resistance, mechanical strength, abrasion resistance, transparency, moldability and the like.

By adding a crosslinking agent and a crosslinking accelerator to the fluorine-containing elastomer composition of the present invention, a crosslinkable fluorine-containing elastomer composition can be obtained.

As the cross-linking system, a cross-linking system generally used for a fluorine-containing elastomer can be applied.
Examples include a triazine cross-linking system, a peroxide cross-linking system, a polyol cross-linking system, and a polyamine cross-linking system. Further, crosslinking by radiation, electron beam, ultraviolet ray, or the like is also possible.

The crosslinking agent used in the oxazole crosslinking system, imidazole crosslinking system, and thiazole crosslinking system includes, for example, a compound represented by the formula (I):

[0052]

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(Wherein R ¹ is —SO ₂ —, —O—, —CO
-, An alkylene group having 1 to 6 carbon atoms, a perfluoroalkylene group having 1 to 10 carbon atoms or a bond, one of R ² and R ³ is -NH ₂ and the other is -NH ₂ , -OH or- A bisamino (thio) phenol crosslinking agent or a tetraamine crosslinking agent represented by the formula (I)
I):

[0054]

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(Wherein R ¹ is the same as above, and R ⁴ is

[0056]

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Or

[0058]

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A bisamidrazone-based crosslinking agent represented by the formula:
Formula (III) or (IV):

[0060]

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(Wherein, R _f ² is a perfluoroalkylene group having 1 to 10 carbon atoms)

[0062]

Embedded image

(Wherein, n is an integer of 1 to 10), such as a bisamidoxime-based crosslinking agent.

Further, if necessary, a crosslinking accelerator may be used in combination.

The amount of the crosslinking agent is 0.5 to 10 parts by weight, preferably 1 to 5 parts by weight, and the crosslinking accelerator is 0.1 to 10 parts by weight, based on 100 parts by weight of the fluorine-containing elastomer. Preferably it is 0.2 to 5 parts by weight.

The crosslinking agent used in the peroxide crosslinking system includes, for example, 1,1-bis (t-butylperoxy) -3,5,5-trimethylcyclohexane, 2,5
-Dimethylhexane-2,5-dihydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, α, α-bis (t-butylperoxy) -p-diisopropylbenzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t
-Butylperoxy) -hexyne-3, benzoyl peroxide, t-butylperoxybenzene, 2,5-
Examples thereof include dimethyl-2,5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, and t-butylperoxyisopropyl carbonate.

In the case of a peroxide crosslinking system, it is desirable to use a crosslinking accelerator. Examples of the crosslinking accelerator include triallyl cyanurate, triallyl isocyanurate, triallyl formal, triallyl trimellitate, N, N'-m-phenylenebismaleimide, dipropanegyl terephthalate, diallyl phthalate, and tetraallyl terephthalate amide And triallyl phosphate.

The amount of the crosslinking agent is 0.05 to 10 parts by weight, preferably 1.10 parts by weight, per 100 parts by weight of the elastomer.
0 to 5 parts by weight, and the crosslinking accelerator is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight.

As in the peroxide crosslinking system, it is not necessary to use an inorganic filler or the like for crosslinking, and no color is formed by crosslinking. An elastomer molded article can be provided.

The transparent crosslinked elastomer molded article obtained by the present invention has a haze value of 50% or less, preferably 40% or less, particularly 30% or less.

As the crosslinking agent used in the polyol crosslinking system, a commonly used polyhydroxy aromatic compound can be used, such as 2,2-bis (4-hydroxyphenyl) propane (so-called bisphenol A),
Bis (4-hydroxyphenyl) perfluoropropane (so-called bisphenol AF), resorcinol,
3,5-trihydroxybenzene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,
6-dihydroxynaphthalene, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxystilbene, 2,
6-dihydroxyanthracene, hydroquinone, catechol, 2,2-bis (4-hydroxyphenyl) butane (so-called bisphenol B), 4,4-bis (4-hydroxyphenyl) valeric acid, 2,2-bis (4-hydroxy Phenyl) tetrafluorochloropropane, 4,
4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylketone, tri (4-hydroxyphenyl) methane, 3,3 ', 5,5'-tetrachlorobisphenol A, 3,3', 5,5'- Examples thereof include tetrabromobisphenol A, and alkali metal salts or alkaline earth metal salts thereof.

It is preferable to use a crosslinking accelerator also in the polyol crosslinking system. Examples of the crosslinking accelerator include an ammonium compound, a phosphonium compound, an oxonium compound, a sulfonium compound and the like, and a quaternary ammonium salt and a quaternary phosphonium salt are particularly preferable.

The amount of the crosslinking agent is 0.5 to 5 parts by weight based on 100 parts by weight of the elastomer, and the crosslinking accelerator is 5 to 400 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the crosslinking agent. Department.

The crosslinking agent used in the polyamine crosslinking system includes a polyamine compound. The polyamine compound is a primary amine or a secondary amine that binds two or more basic nitrogens in a molecule, and in many cases, a compound obtained by adjusting these in a salt form to have a mild reactivity. use. As a specific example, for example, alkylenediamines such as ethylenediaminecarbamate, hexamethylenediaminecarbamate, and 4,4'-diaminocyclohexylmethanecarbamate are relatively frequently used. N, N'-dicinnamylidene-
Schiff salts such as 1,6-hexamethylenediamine can also be used. The polyamine aromatic compound having poor basicity can be preferably used in combination with another basic compound. Other basic compounds include, for example, diphenylguanidine, di-O-triguanidine, diphenylthiourea, 2-mercaptoimidazoline and the like, and -NH ₂ and / or A compound having -NH-, a divalent metal hydroxide, or the like.

The amount of the crosslinking agent is 0.1 to 10 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the elastomer.
-5 parts by weight.

Other additives include known additives such as fillers, pigments, ultraviolet absorbers and antioxidants other than the fluororesin particles of the present invention.

Other fillers include, for example, inorganic fillers such as carbon black (especially graphitized carbon black, silicon oxide, titanium oxide, and alumina) and organic fillers such as polyimide, etc. The blending amount is 100% by weight of elastomer. 100 parts by weight or less, preferably 1 to
50 parts by weight.

The above-mentioned additives such as a cross-linking agent, a cross-linking accelerator and other organic or inorganic fillers may be added at the time of the co-coagulation if possible. After production, they may be mixed. The mixing method may be a kneading method using a conventionally known roll.

The crosslinked elastomer composition containing the finely dispersed fluororesin particles thus obtained is kneaded and crosslinked to produce a crosslinked molded product. As a kneading method, a usual method, for example, roll kneading, kneading, and the like can be adopted, and a molding method is also a usual compression molding method, injection molding method,
A molding method such as an extrusion molding method or a transfer molding method can be employed. The molding conditions may be the same as the conventional conditions.

The obtained cross-linked molded product maintains its transparency when the matrix is a transparent elastomer when no other filler is contained. Although the transparency may slightly decrease, the visible light transmittance of 20% or more of that of the elastomer alone is still maintained.

The molded article of the present invention is excellent in heat resistance, mechanical strength, post-processability, plasma resistance and gas barrier properties.
Further, since the finely dispersed fluororesin fine particles hardly fall off from the matrix elastomer, there is little possibility that particles are generated even when they are used, for example, as sealing parts of a semiconductor manufacturing apparatus.

The fluorine-containing elastomer composition of the present invention is suitable as molded articles shown in the following Tables 1, 2 and 3 by utilizing its excellent properties.

[0083]

[Table 1]

[0084]

[Table 2]

[0085]

[Table 3]

More specifically, it can be used by being incorporated in the following semiconductor manufacturing apparatus. (1) Etching equipment Dry etching equipment Plasma etching equipment Reactive ion etching equipment Reactive ion beam etching equipment Sputter etching equipment Ion beam etching equipment Wet etching equipment Ashing equipment

(2) Cleaning device Dry etching cleaning device UV / O ₃ cleaning device Ion beam cleaning device Laser beam cleaning device Plasma cleaning device Gas etching cleaning device Extraction cleaning device Soxhlet extraction cleaning device High-temperature high-pressure extraction cleaning device Microwave extraction cleaning device Supercritical extraction cleaning equipment

(3) Exposure equipment Stepper Coater / Developer

(4) Polishing device CMP device

(5) Film forming apparatus CVD apparatus Sputtering apparatus

(6) Diffusion / ion implantation device Oxidation diffusion device ion implantation device

When a melt-processable fluororesin is used as the matrix polymer, the molded article has high strength,
Excellent properties such as improved chemical resistance can be imparted in a well-balanced manner.

PFA, FEP, ET and the like can be used as the melt-processable fluororesin used as the matrix polymer.
FE, PCTFE, ECTFE, etc.
Value (372 ° C., 5 kg) is 0.1 to 50 g / 10 min,
Preferably, it is 5 to 30 g / 10 min.

Among them, a perfluoro-based resin is preferable because of its excellent heat resistance and chemical resistance. In particular,
For example, TFE / HFP (HFP content 5-15 mol%), TFE / HFP / PAVE (HFP content 5-15 mol%)
Mol%, PAVE content 0.5-3 mol%), TFE / P
AVE (PAVE content: 0.5 to 8 mol%).

As a method of uniformly mixing and finely dispersing specific fluororesin particles as a filler into a melt-processable fluororesin as a matrix polymer, the co-coagulation method described for the above-mentioned fluoroelastomer composition is preferable. Can be adopted.

The non-melt-processable fluororesin particles as a filler are 1 to 50 parts by weight, especially 5 to 50 parts by weight, per 100 parts by weight of the matrix polymer (melt-processable fluororesin).
-30 parts by weight are preferred. Further, various additives described for the fluorine-containing elastomer composition can be used in the same manner.

Such a fluororesin composition utilizes heat resistance, non-staining adhesion prevention property, chemical resistance, cleanness, etc.
It is suitable for manufacturing molded products such as electric wire covering materials, chemical solution containers, tubes and hoses, pump lining materials, etching carriers, and the like.

[0098]

EXAMPLES The present invention will be described below with reference to Synthesis Examples and Examples, but the present invention is not limited to only these Synthesis Examples and Examples.

Synthesis Example 1 (Emulsion of fluororesin fine particles)
Production of stainless steel without ignition source
3 liters of pure water and emulsifier
Then C_ThreeF₇OCF (CF_Three) CF_TwoOCF (CF _Three) CO
ONH_Four30 g of dinatto hydrogen phosphate as a pH adjuster
Charge 0.27 g of lithium and 12 hydrates.
After thoroughly displacing with degassing, stir at 600 rpm.
Then, the temperature was raised to 80 ° C., and tetrafluoroethylene (TF
E) and perfluoro (methyl vinyl ether) (PMV
E) mixed gas (TFE / PMVE = 88/12 mol)
) Was charged so that the internal pressure became 0.20 MPa.
Then, 2.5 mg / Am of ammonium persulfate (APS)
Start reaction by injecting 4 ml of aqueous solution with a concentration of ml under nitrogen pressure
did.

As the polymerization proceeds, the internal pressure becomes 0.15 MPa.
At the time of dropping to the TFE / PMVE mixed gas (T
FE / PMVE = 95/5 molar ratio) with an internal pressure of 0.20M
It was press-fitted with nitrogen gas to Pa. Thereafter, as the reaction proceeds, the TFE / PMVE mixed gas (95 /
(5 mol ratio), and the pressure was repeatedly increased and decreased between 0.15 and 0.20 MPa.

4.5 hours after the start of the polymerization reaction, TFE
When the total charged amount of PMVE and PMVE reached 331 g, the autoclave was cooled and unreacted monomers were released to obtain an emulsion of fine particles of fluororesin (average particle size: 44 nm) having a solid content of 9.7% by weight. . The average particle size is obtained by mixing 120 mg of the emulsion with 4.4 g of dimethyl sulfoxide, and using LPA-3000, 310 manufactured by Otsuka Electronics Co., Ltd.
It was measured at zero.

A part of this emulsion was taken out, coagulated by adding nitric acid, and the precipitate was washed and dried to obtain white fluororesin fine particles. This had a composition ratio of TFE / PMVE = 94.5 / 5.5 (mol%) in ¹⁹ F-NMR analysis.
Met.

The melt flow rate (MFR) of the fluororesin particles was 0.01 g / 10 min under the conditions of a load of 5 kg and holding at 372 ° C. for 5 minutes.
^st the run) the melting temperature was 290 ° C., a melting point (2 ^nd run) was 264 ° C..

Synthesis Example 2 (Production of Emulsion of Fluororesin Fine Particles) In Synthesis Example 1, the initial monomer charge composition was changed to TFE / P
An emulsion of fluororesin particles having an average particle size of 56 nm was produced in the same manner except that MVE was 88/12 (molar ratio) and the additional monomer composition was TFE / PMVE = 98/2 (molar ratio). . This had a composition ratio of TFE / PMVE = 97.5 / 2.5 (mol%) in ¹⁹ F-NMR analysis.

Melt flow rate of the fluororesin particles
(MFR) is under the condition of 5 kg load and 372 ° C for 5 minutes.
0.01 g / 10 min or less, the first measured by DSC
Period (1 ^strun) The melting temperature is 314 ° C and the melting point (2^ndru
n) was 290 ° C.

Synthesis Example 3 (Production of Emulsion of Fluororesin Fine Particles) In Synthesis Example 1, the initial monomer charge composition was changed to TFE / P
An emulsion of fluorine-containing resin particles having an average particle diameter of 46 nm was produced in the same manner except that MVE was 82/18 (molar ratio) and the additional monomer composition was TFE / PMVE = 92/8 (molar ratio). . This had a composition ratio of TFE / PMVE = 91.7 / 8.3 (mol%) in ¹⁹ F-NMR analysis.

[0107] The melt flow rate of the fluorine resin particles (MFR) is in the condition of holding the load 5 kg, 372 ° C. 5 min 0.1 g / 10min, the initial (1 ^st measured by DSC
run) melt temperature was 262 ° C., a melting point (2 ^nd run) 2
36 ° C.

Synthesis Example 4 (Evaluation of fluorine-containing elastomer particles)
Manufacture of marshon) Stainless steel with a volume of 3 liters without ignition source
1 liter of pure water and emulsifier
Then C_ThreeF₇OCF (CF_Three) CF_TwoOCF (CF _Three) CO
ONH_Four10 g, dinatto hydrogen phosphate as a pH adjuster
Charge 0.09 g of lithium and 12 hydrates.
After thoroughly displacing with degassing, stir at 600 rpm.
Then, the temperature was raised to 53 ° C and tetrafluoroethylene (TF
E) and perfluoro (methyl vinyl ether) (PMV
E) mixed gas (TFE / PMVE = 25/75 mol)
) Was charged such that the internal pressure became 0.78 MPa.
Then, 264 mg / ammonium persulfate (APS)
The reaction is started by injecting 20 ml of aqueous solution of
Started.

Due to the progress of the polymerization, the internal pressure becomes 0.69 MPa.
At the time when it descends to CF ₂ = CFOCF ₂ CF (C
2.2 g of F ₃ ) OCF ₂ CF ₂ CN (CNVE) was injected under nitrogen pressure. Then, 4.7 g of TFE and 5.3 g of PMVE were respectively injected under their own pressure so that the pressure became 0.78 MPa. Thereafter, as the reaction progresses, TFE and PMVE are similarly injected, and 0.69 to 0.78
The pressure was repeatedly increased and decreased between MPa, and when the total amount of TFE and PMVE became 70 g, 2.2 g of CNVE was injected at a nitrogen pressure.

Six hours after the start of the polymerization reaction, when the total charged amount of TFE and PMVE reached 130 g,
The autoclave was cooled and unreacted monomers were discharged to obtain 1160 g of an emulsion of fluorine-containing elastomer particles (A-2) having a solid content of 11.3% by weight.

100 g of this emulsion was mixed with water 3
The mixture was diluted with 00 g and slowly added to 280 g of a 3.5% by weight aqueous hydrochloric acid solution with stirring. After the addition, the mixture was further stirred for 5 minutes, and the obtained coagulated product was separated by filtration. The obtained elastomer particles were further washed with 200 g of HCFC-141b and filtered. Washing with HCFC-141b and filtration were repeated four times, and then vacuum dried at 60 ° C. for 72 hours to obtain 11.2 g of a fluorine-containing elastomer.

The fluorine-containing elastomer was obtained from ¹⁹ F-
When the composition ratio was determined by NMR analysis, TFE / PM
VE / CNVE = 60.4 / 38.9 / 0.7 (mol%).

Example 1 The emulsion of the fluoroelastomer particles obtained in Synthesis Example 4 and the emulsion of the fluororesin fine particles obtained in Synthesis Examples 1 to 3 were mixed (solid content ratio: fluoroelastomer / fluororesin = (85/15 weight ratio), and dropped into a stirring 9% aqueous nitric acid solution over 10 minutes to perform co-coagulation. The obtained co-coagulated product was washed with water and dried to obtain an elastomer composition in which fluororesin fine particles were finely dispersed in a fluoroelastomer.

Then, the obtained elastomer composition 100 was obtained.
In weight parts, 2,2-bis-[(3-amino-
4-phenylamino) phenyl] hexafluoropropane (Journal of Polymer Science, edited by Polymer Chemistry, Vol. 20, 2381-239)
3 (synthesized by the method described in 1982)) and kneaded with an open roll at 40 ° C. to obtain a crosslinkable elastomer composition. The winding property on the roll was observed on the basis described later in the kneading. Table 4 shows the results
Shown in

Further, the crosslinkable elastomer composition was mixed with 170
Press-crosslink at 15 ° C for 15 minutes, then at 204 ° C for 18 hours,
Subsequently, oven crosslinking was performed at 288 ° C. for 18 hours to obtain a crosslinked product. The physical properties of this crosslinked product were measured under normal conditions. Further, an O-ring (P-24) was manufactured under the same crosslinking conditions, and the compression set (CS) was measured. Table 4 shows the results.

(Roll wrapping property) ロ ー ル: The surface of the roll is sufficiently wound around the roll at room temperature. Δ: Rolling occurs when the roll surface temperature is set to 50 ° C. ×: No winding occurs even when the roll surface temperature is 50 ° C.

(Physical properties under normal conditions) The 100% modulus, tensile strength, tensile elongation and hardness (JIS A hardness) under normal conditions (25 ° C) are measured according to JIS K6301.

(Compression Set) The compression set (%) after 70 hours at 275 ° C. and 25% compression is measured according to JIS K6301.

[0119]

[Table 4]

As shown in Table 4, when the specific fluororesin particles of the present invention are blended as a filler, excellent mechanical properties are well balanced and a small value of compression set is given even at a high temperature of 275 ° C. Can be.

Example 4 Emulsion of melt-processable TFE / HFP / perfluoro (propyl vinyl ether) (= 87.5 / 11.5 / 1.0 mol ratio) particles and fluororesin fine particles obtained in Synthesis Example 1 (Solid content ratio: FEP)
/ Fluororesin = 70/30 weight ratio), 9% stirring
Co-coagulation was carried out by dropping into a nitric acid aqueous solution over 10 minutes. The obtained co-coagulated product was washed with water and dried to obtain a fluororesin composition in which fluororesin fine particles were finely dispersed in FEP.

The fluororesin composition was press-molded at 372 ° C. to produce a sheet (1 mm thick). When the mechanical strength (JIS K6891) of this sheet was measured, the tensile strength was 32.8 MPa and the tensile elongation was 291%. Then, after heating this sheet at a temperature of 250 ° C. for 100 hours, the mechanical strength was measured. As a result, the tensile strength was 33.1 MPa and the tensile elongation was 300%, and no decrease in mechanical properties was observed.

[0123]

According to the present invention, heat resistance, mechanical strength,
Further, a composition capable of providing a molded article having excellent transparency and the like can be provided.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hirofumi Nishibayashi 1-1, Nishiichitsuya, Settsu-shi, Osaka Daikin Industries, Ltd. Yodogawa Works (72) Inventor Hiroyuki Tanaka 1-1-1, Nishiichitsuya, Settsu-shi, Osaka Daikin Industries Inside Yodogawa Works, Ltd. (72) Inventor Go Noguchi 1-1, Nishi-Itsuya, Settsu-shi, Osaka Daikin Industries, Ltd. Inside Yodogawa Works, Ltd. F-term in Yodogawa Works (reference) 4J002 BB10W BD14W BD15W BD152 BD16W FD010 FD140 GM00 4J100 AC26P AE35Q CA04 DA24 EA09 JA28

Claims (11)

[Claims] 1. Fluororesin particles having a melting point of 230 to 300 ° C. and an average particle diameter of 100 nm or less which cannot be melt-processed, and are prepared at 327 ° C. and 5 ° C. in accordance with ASTM D3307.
The melt flow rate measured under kg load is 0.005
Fluororesin particles of 0.1 g / 10 min. 2. The fluororesin particles according to claim 1, wherein the fluororesin particles are fluorocopolymer particles of tetrafluoroethylene and a perfluoroolefin other than tetrafluoroethylene. 3. The fluororesin particles according to claim 2, wherein the fluorocopolymer particles contain 90 mol% or more of tetrafluoroethylene units. 4. The fluororesin particles according to claim 2, wherein the content of perfluoroethylene units other than tetrafluoroethylene is 2 to 9 mol%. 5. The fluororesin particles according to claim 2, wherein the perfluoroolefin copolymerized with tetrafluoroethylene is perfluoro (alkyl vinyl ether). 6. An aqueous dispersion of fluororesin particles, wherein the fluororesin particles according to claim 1 are dispersed in water. 7. A fluoroelastomer composition comprising a fluoroelastomer and the fluororesin particles according to claim 1. 8. The fluoroelastomer composition according to claim 7, wherein the fluoroelastomer is a perfluoroelastomer. 9. A sealing part for a semiconductor manufacturing apparatus obtained by molding from the elastomer composition according to claim 7 or 8. 10. A fluororesin which can be melt-processed, and a fluorine resin.
A fluororesin composition comprising the fluororesin particles of (1) to (5). 11. The fluorine-containing resin composition according to claim 10, wherein the melt-processable fluorine resin is a perfluoro resin.