JP2017020014A - Fluorine resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally stable fluorine resin hardly generating foam during melting molding or burning.SOLUTION: There is provided a fluorine resin containing a vinylidene fluoride unit and having a -CONHgroup at a main chain terminal and the vinylidene fluoride unit is 10.0 to 100 mol% of the total monomer unit constituting the fluorine resin.SELECTED DRAWING: None

Description

The present invention relates to a fluororesin containing vinylidene fluoride units.

Fluororesin containing a vinylidene fluoride unit is excellent in heat resistance and chemical resistance, and at the same time has a large difference between the melting point and the thermal decomposition temperature and is easy to process.

As a method for producing a fluororesin containing a vinylidene fluoride unit, for example, Patent Document 1 describes a method for producing a vinylidene fluoride polymer using a dialkyl peroxydicarbonate.

JP-A-11-193269

However, when dialkyl peroxydicarbonate is used as a polymerization initiator, a thermally unstable group is generated at the end of the main chain of the resulting fluororesin. When the fluororesin is melted by heating and molded, an unstable group is decomposed to generate gas, which causes a problem that foam marks remain in the obtained molded body.

An object of the present invention is to provide a fluororesin that is a thermally stable fluororesin and does not cause foaming during melt molding or firing.

The present invention is a fluororesin containing a vinylidene fluoride unit having a —CONH ₂ group at the end of the main chain, and the vinylidene fluoride unit is 10.0 to 100 of all monomer units constituting the fluororesin. It is a fluororesin characterized by being mol%.

The fluororesin further contains a tetrafluoroethylene unit, the vinylidene fluoride unit is 10.0 to 70.0 mol% of the total monomer units constituting the fluororesin, and the tetrafluoroethylene unit constitutes the fluororesin It is preferable that it is 30.0-85.0 mol% of all the monomer units to perform.

The fluororesin further includes a tetrafluoroethylene unit and at least one ethylenically unsaturated monomer unit selected from the group consisting of ethylenically unsaturated monomers represented by the formulas (1) and (2). The vinylidene fluoride unit is 10.0 to 44.9 mol% of the total monomer units constituting the fluororesin, and the tetrafluoroethylene unit is 50.0 to 85.0 of the total monomer units constituting the fluororesin. It is preferable that the ethylenically unsaturated monomer unit is 0.1 to 5.0 mol% of all monomer units constituting the fluororesin.
Formula (1): CX ¹¹ X ¹² = CX ¹³ (CX ¹⁴ X ¹⁵ ) _n11 X ¹⁶
(In the formula, X ^{11 to} X ¹⁶ are the same or different and represent H, F or Cl, and n ¹¹ represents an integer of 0 to 8, except for tetrafluoroethylene and vinylidene fluoride.)
Equation ^{(2): CX 21 X 22} = CX 23 -O (CX 24 X 25) n21 X 26
(Wherein X ^{21 to} X ²⁶ are the same or different and represent H, F or Cl, and n ²¹ represents an integer of 0 to 8)

Since the fluororesin of the present invention has the above configuration, it is thermally stable. Therefore, since foaming due to unstable groups does not occur during melt molding, a molded body without foaming marks can be obtained.
Since the molded article of the present invention has the above-described configuration, there is no foaming trace and the appearance is good.
Since the powder coating material of the present invention has the above-described configuration, foaming due to an unstable group does not occur during firing, so that a coating film having no foaming trace can be formed.

Hereinafter, the present invention will be specifically described.

The fluororesin of the present invention contains 10.0 to 100 mol% vinylidene fluoride units of all monomer units constituting the fluororesin, and has a -CONH ₂ group at the end of the main chain. Features.

When the -CONH ₂ group in the main chain terminal is present, in the infrared absorption spectrum of the fluorine resin obtained by infrared absorption spectrum analysis, a peak derived from N-H of the -CONH ₂ group to the absorption wavelength 3400～3470Cm ^-1 appear. By confirming the presence of this peak, it can be confirmed that a —CONH ₂ group is present at the end of the main chain. The —CONH ₂ group is a thermally stable end group.

The fluororesin preferably has 20 or more —CONH ₂ groups per 10 ⁶ main chain carbon atoms at the end of the main chain. The number of —CONH ₂ groups is more preferably 30 or more. An upper limit is not specifically limited, 500 or less may be sufficient and it may be 250 or less.

The number of —CONH ₂ groups is obtained by performing infrared absorption spectrum analysis on a film having a thickness of 200 μm, and the absorbance of the peak appearing at 2900 to 3100 cm ⁻¹ due to the CH ₂ group of the main chain in the obtained infrared absorption spectrum. The absorbance A of the peak due to the NH bond of the terminal NH ₂ group appearing in the vicinity of 3400 to 3470 cm ^{−1 of the} spectrum is obtained and calculated by the following formula.
Number of —CONH ₂ groups per 10 ⁶ main chain carbon atoms = 4258 × A

From the viewpoint of thermal stability, the fluororesin preferably has 0 to 40 unstable terminal groups per 10 ⁶ main chain carbon atoms at the main chain terminals. The number of unstable terminal groups is more preferably 0-20, and still more preferably 0.

The unstable terminal group may be at least one selected from the group consisting of —COF group, —COOH group, —COOCH ₃ group, —CF═CF ₂ group, —OH group, and ROCOO— group. R in the ROCOO- group is preferably a linear or branched alkyl group, and the alkyl group may have 1 to 15 carbon atoms.

The number of the unstable terminal groups is the absorbance of a peak appearing at 2900 to 3100 cm ⁻¹ due to the CH ₂ group of the main chain in the obtained infrared absorption spectrum by performing infrared absorption spectrum analysis on a film having a thickness of 200 μm. Is normalized to 1.0, and the absorbance A of the peak due to the unstable end group appearing in the spectrum is obtained and calculated by the following formula. The coefficient K is as shown in Table 1.
The number of backbone unstable terminal group of 10 ⁶ per carbon = K × A

The fluororesin preferably further contains a tetrafluoroethylene unit. In this case, the vinylidene fluoride unit is 10.0 to 70.0 mol% of all monomer units constituting the fluororesin, and the tetrafluoroethylene unit is 30.0 to 85 of all monomer units constituting the fluororesin. It is preferably 0.0 mol%. More preferably, the vinylidene fluoride unit is 15.0 to 60.0 mol% of all monomer units constituting the fluororesin, and the tetrafluoroethylene unit is 40.0% to all monomer units constituting the fluororesin. 85.0 mol%.

The fluororesin further contains a tetrafluoroethylene unit and at least one ethylenically unsaturated monomer unit selected from the group consisting of ethylenically unsaturated monomers represented by formulas (1) and (2). It is preferable.

Formula (1): CX ¹¹ X ¹² = CX ¹³ (CX ¹⁴ X ¹⁵ ) _n11 X ¹⁶
(In the formula, X ^{11 to} X ¹⁶ are the same or different and represent H, F or Cl, and n ¹¹ represents an integer of 0 to 8, except for tetrafluoroethylene and vinylidene fluoride.)

Equation ^{(2): CX 21 X 22} = CX 23 -O (CX 24 X 25) n21 X 26
(Wherein X ^{21 to} X ²⁶ are the same or different and represent H, F or Cl, and n ²¹ represents an integer of 0 to 8)

Examples of the ethylenically unsaturated monomer represented by the formula (1) include CF ₂ = CFCl, CF ₂ = CFCF ₃ , and the following formula (3):
_{CH 2 = CF- (CF 2)} n11 X 16 (3)
(Wherein X ¹⁶ and n ¹¹ are the same as above), and the following formula (4):
_{CH 2 = CH- (CF 2)} n11 X 16 (4)
(Wherein X ¹⁶ and n ¹¹ are the same as above)
It is preferably at least one selected from the group consisting of: CF ₂ = CFCl, CH ₂ = CFCF ₃ , CH ₂ = CH-C ₄ F ₉ , CH ₂ = CH-C ₆ F ₁₃ , CH ₂ = more preferably at least one selected from the group consisting of _CF-C 3 _{F 6} H, and _{CF 2 = CFCF 3, CF 2} = CFCl, CH 2 = CH-C 4 F 9, CH 2 = CH- C ₆ F _{13, CH} and still more preferably from _{2 = CF-C 3 F 6} H , and _CH 2 = CFCF ₃ is at least one selected.

The ethylenically unsaturated monomer represented by the formula _(2), selected from the group consisting of _{CF 2 = CF-OCF 3,} CF 2 = CF-OCF 2 CF 3 and _{CF 2 = CF-OCF 2 CF} 2 CF 3 It is preferable that it is at least one kind.

When the fluororesin further has a tetrafluoroethylene unit and the ethylenically unsaturated monomer unit, the vinylidene fluoride unit is 10.0 to 44.9 mol% of the total monomer units constituting the fluororesin, The ethylene unit is 50.0 to 85.0 mol% of all monomer units constituting the fluororesin, and the ethylenically unsaturated monomer unit is 0.1 to 5.0 mol of all monomer units constituting the fluororesin. % Is preferred. More preferably, the vinylidene fluoride unit is 15.0 to 49.9 mol% of all monomer units constituting the fluororesin, and the tetrafluoroethylene unit is 50.0 to 50.0% of all monomer units constituting the fluororesin. 70.0 mol%, and the ethylenically unsaturated monomer unit is 0.1 to 5.0 mol% of all monomer units constituting the fluororesin.
When the fluororesin further has a tetrafluoroethylene unit and the ethylenically unsaturated monomer unit, the vinylidene fluoride unit is 10.0 to 49.9 mol% of all monomer units constituting the fluororesin, The tetrafluoroethylene unit is 50.0 to 85.0 mol% of the total monomer units constituting the fluororesin, and the ethylenically unsaturated monomer unit is 0.1 to 5% of the total monomer units constituting the fluororesin. It may be 0 mol%.

The fluororesin of the present invention is
55.0-90.0 mol% tetrafluoroethylene,
5.0-49.9 mol% vinylidene fluoride, and
0.1 to 10.0 mol% of an ethylenically unsaturated monomer represented by the formula (1),
It is preferable that it is a copolymer containing these copolymer units.

More preferably,
55.0-85.0 mol% tetrafluoroethylene,
10.0-44.9 mol% vinylidene fluoride, and
0.1 to 5.0 mol% of an ethylenically unsaturated monomer represented by the formula (1),
It is a copolymer containing the copolymerization unit.

More preferably,
55.0-85.0 mol% tetrafluoroethylene,
13.0-44.9 mol% vinylidene fluoride, and
0.1 to 2.0 mol% of an ethylenically unsaturated monomer represented by the formula (1),
It is a copolymer containing the copolymerization unit.

In addition to improving the mechanical strength of the fluororesin at high temperatures, the low permeability of the fluororesin is particularly excellent, so that the ethylenically unsaturated monomer represented by the formula (1) is CF ₂ = CFCl, CH ₂ = _CH-C 4 _F 9, particularly preferably _{CH 2 = CH-C 6 F} 13 and _{CH 2 = CF-C 3 F} 6 of at least one monomer selected from the group consisting of H. Preferably, the group ethylenically unsaturated monomer represented by the formula (1) is composed of _{CH 2 = CH-C 4 F} 9, CH 2 = CH-C 6 F 13 and _{CH 2 = CF-C 3 F} 6 H Tetrafluoroethylene having at least one monomer selected from 55.0 to 80.0 mol% of a fluororesin,
19.5-44.9 mol% vinylidene fluoride, and
0.1 to 0.6 mol% of an ethylenically unsaturated monomer represented by the formula (1),
It is a copolymer containing the copolymer unit of this.

The fluororesin of the present invention is
58.0-85.0 mol% tetrafluoroethylene,
10.0-41.9 mol% vinylidene fluoride, and
0.1 to 5.0 mol% of an ethylenically unsaturated monomer represented by the formula (1),
A copolymer containing the copolymer unit may be used.

The fluororesin of the present invention is
55.0-90.0 mol% tetrafluoroethylene,
9.2-44.2 mol% vinylidene fluoride, and
0.1 to 0.8 mol% of an ethylenically unsaturated monomer represented by the formula (2),
It is also preferable that it is a copolymer containing these copolymer units.

More preferably,
58.0-85.0 mol% tetrafluoroethylene,
14.5 to 39.9 mol% vinylidene fluoride, and
0.1 to 0.5 mol% of an ethylenically unsaturated monomer represented by the formula (2),
It is a copolymer containing the copolymerization unit.

The fluororesin of the present invention is
55.0-90.0 mol% tetrafluoroethylene,
5.0-44.8 mol% vinylidene fluoride,
0.1 to 10.0 mol% of an ethylenically unsaturated monomer represented by the formula (1), and
0.1 to 0.8 mol% of an ethylenically unsaturated monomer represented by the formula (2),
It is also preferable that it is a copolymer containing these copolymer units.

More preferably,
55.0-85.0 mol% tetrafluoroethylene,
9.5-44.8 mol% vinylidene fluoride,
0.1 to 5.0 mol% of an ethylenically unsaturated monomer represented by the formula (1), and
0.1 to 0.5 mol% of an ethylenically unsaturated monomer represented by the formula (2),
It is a copolymer containing the copolymerization unit.

More preferably 55.0-80.0 mol% tetrafluoroethylene,
19.8-44.8 mol% vinylidene fluoride,
0.1 to 2.0 mol% of an ethylenically unsaturated monomer represented by the formula (1), and
0.1 to 0.3 mol% of an ethylenically unsaturated monomer represented by the formula (2),
It is a copolymer containing the copolymerization unit. When the fluororesin of the present invention has this composition, it is particularly excellent in low permeability.

The fluororesin of the present invention is
58.0-85.0 mol% tetrafluoroethylene,
9.5-39.8 mol% vinylidene fluoride,
0.1 to 5.0 mol% of an ethylenically unsaturated monomer represented by the formula (1), and
0.1 to 0.5 mol% of an ethylenically unsaturated monomer represented by the formula (2),
A copolymer containing the copolymer unit may be used.

When the content of each monomer is within the above range, the fluororesin of the present invention is excellent in mechanical strength, chemical resistance and low permeability at high temperatures. The low permeability at a high temperature is, for example, low permeability to methane, hydrogen sulfide, CO ₂ , methanol, hydrochloric acid and the like.

The content of each monomer in the copolymer can be calculated by appropriately combining NMR and elemental analysis depending on the type of monomer.

The fluororesin of the present invention preferably has a melt flow rate (MFR) of 0.1 to 100 g / 10 min, more preferably 0.1 to 50 g / 10 min, and 0.1 to 10 g / 10 min. More preferably.

The above MFR is based on ASTM D3307-01 and uses a melt indexer (manufactured by Toyo Seiki Co., Ltd.) at 297 ° C. under a load of 5 kg and the mass of the polymer flowing out from a nozzle having an inner diameter of 2 mm and a length of 8 mm per 10 minutes. (G / 10 minutes).

The melting point of the fluororesin of the present invention is preferably 180 ° C. or higher, and the upper limit may be 290 ° C. A more preferred lower limit is 200 ° C and an upper limit is 270 ° C.

The melting point is measured by using a differential scanning calorimeter RDC220 (manufactured by Seiko Instruments) according to ASTM D-4591 at a heating rate of 10 ° C./min, and the temperature corresponding to the peak of the endothermic curve obtained is measured. The melting point.

The fluororesin of the present invention preferably has a thermal decomposition start temperature (1% mass loss temperature) of 360 ° C. or higher. A more preferred lower limit is 370 ° C., and a more preferred lower limit is 380 ° C. If the said thermal decomposition start temperature is in the said range, an upper limit can be 410 degreeC, for example.

The thermal decomposition start temperature is a temperature at which 1% by mass of the fluororesin subjected to the heating test is decomposed, and can be determined by the following method.
Using a differential heat / thermogravimetric measuring device (TG-DTA6200 (manufactured by Hitachi High-Tech Science Co., Ltd.)), using fluororesin powder or 10 mg of pellets for measurement, the temperature was raised at 10 ° C./min in an air atmosphere, and 1 mass Measure the temperature when decreasing by%.

The fluororesin of the present invention can be produced by a production method including a step of obtaining a fluororesin by polymerizing vinylidene fluoride in the presence of a polymerization initiator and a step of amidating the fluororesin.

The amidation treatment can be performed by bringing the fluororesin obtained by polymerization into contact with aqueous ammonia, ammonia gas, or a nitrogen compound that can generate ammonia.

By adding ammonia water to the fluororesin obtained by polymerization, the fluororesin before treatment can be brought into contact with ammonia water. As said ammonia water, what is the density | concentration of 0.01-28 mass% of ammonia can be used, and contact time may be 1 minute-24 hours. The number of —CONH ₂ groups can be adjusted by adjusting the concentration of ammonia water and the contact time.

As a method for bringing the fluororesin before the treatment into contact with the ammonia gas, there is a method in which the fluororesin before the treatment is installed in the reaction vessel and the ammonia gas is supplied into the reaction vessel. The supply of ammonia gas into the reaction vessel may be performed after mixing with a gas inert to amidation to form a mixed gas.

The gas inert to the amidation is not particularly limited, and examples thereof include nitrogen gas, argon gas, and helium gas. The ammonia gas is preferably 1% by mass or more of the mixed gas, more preferably 10% by mass or more, and may be 80% by mass or less as long as it is within the above range.

The amidation treatment is preferably performed at 0 ° C. or more and 100 ° C. or less, more preferably 5 ° C. or more, further preferably 10 ° C. or more, more preferably 90 ° C. or less, and further preferably 80 ° C. or less. It is. If the temperature is too high, the fluororesin may be decomposed or fused. If it is too low, the treatment may take a long time, which is not preferable from the viewpoint of productivity.

The time of the amidation treatment is usually about 1 minute to 24 hours, although it depends on the amount of the fluororesin.

The amidation treatment may be carried out so that the ratio of —CONH ₂ group of the fluororesin after the amidation treatment to 25% or more of the unstable terminal group of the fluororesin before the amidation treatment is present. preferable. The ratio is more preferably 50% or more, further preferably 60% or more, particularly preferably 80% or more, and may be 100%. The greater the ratio, the higher the thermal stability of the resulting fluororesin.
The unstable terminal group may be at least one selected from the group consisting of —COF group, —COOH group, —COOCH ₃ group, —CF═CF ₂ group, —OH group, and ROCOO— group. R in the ROCOO- group is preferably a linear or branched alkyl group, and the alkyl group may have 1 to 15 carbon atoms.

The polymerization of the vinylidene fluoride may be solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization, etc., but emulsion polymerization or suspension polymerization is preferable from the viewpoint of easy industrial implementation, and suspension polymerization. Is more preferable.

As the polymerization initiator, an oil-soluble radical polymerization initiator or a water-soluble radical polymerization initiator can be used, but an oil-soluble radical polymerization initiator is preferable.

The oil-soluble radical polymerization initiator may be a known oil-soluble peroxide, for example, dialkyl such as diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, disec-butyl peroxydicarbonate, etc. Peroxyesters such as peroxycarbonates, t-butylperoxyisobutyrate and t-butylperoxypivalate, and dialkyl peroxides such as di-t-butylperoxide are also used as di (ω-hydro -Dodecafluoroheptanoyl) peroxide, di (ω-hydro-tetradecafluoroheptanoyl) peroxide, di (ω-hydro-hexadecafluorononanoyl) peroxide, di (perfluorobutyryl) peroxide, di (Perful Valeryl) Par Xide, Di (perfluorohexanoyl) peroxide, Di (perfluoroheptanoyl) peroxide, Di (perfluorooctanoyl) peroxide, Di (perfluorononanoyl) peroxide, Di (ω-chloro-hexafluoro Butyryl) peroxide, di (ω-chloro-decafluorohexanoyl) peroxide, di (ω-chloro-tetradecafluorooctanoyl) peroxide, ω-hydro-dodecafluoroheptanoyl-ω-hydrohexadecafluoro Nonanoyl-peroxide, ω-chloro-hexafluorobutyryl-ω-chloro-decafluorohexanoyl-peroxide, ω-hydrododecafluoroheptanoyl-perfluorobutyryl-peroxide, di (dichloropentafluorobutanoy ) Peroxide, di (trichlorooctafluorohexanoyl) peroxide, di (tetrachloroundecafluorooctanoyl) peroxide, di (pentachlorotetradecafluorodecanoyl) peroxide, di (undecachlorodotriacontafluoro) Typical examples include docosanoyl) peroxide di [perfluoro (or fluorochloro) acyl] peroxides.

The water-soluble radical polymerization initiator may be a known water-soluble peroxide, for example, ammonium salts such as persulfuric acid, perboric acid, perchloric acid, perphosphoric acid, percarbonate, potassium salts, sodium salts. , T-butyl permalate, t-butyl hydroperoxide and the like. A reducing agent such as sulfites and sulfites may be used in combination with the peroxide, and the amount used may be 0.1 to 20 times the peroxide.

As the oil-soluble radical polymerization initiator, dialkyl peroxycarbonate is preferable, and is selected from the group consisting of diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, and disec-butyl peroxydicarbonate. At least one is preferred.

In the above polymerization, a surfactant, a chain transfer agent, and a solvent can be used, and conventionally known ones can be used.

As the surfactant, a known surfactant can be used. For example, a nonionic surfactant, an anionic surfactant, a cationic surfactant, or the like can be used. Among these, fluorine-containing anionic surfactants are preferable, and may include ether-bonded oxygen (that is, oxygen atoms may be inserted between carbon atoms), linear or branched having 4 to 20 carbon atoms. A fluorine-containing anionic surfactant is more preferable. The addition amount (with respect to polymerization water) is preferably 50 to 5000 ppm.

Examples of the chain transfer agent include hydrocarbons such as ethane, isopentane, n-hexane and cyclohexane; aromatics such as toluene and xylene; ketones such as acetone; acetates such as ethyl acetate and butyl acetate; Examples include alcohols such as methanol and ethanol; mercaptans such as methyl mercaptan; halogenated hydrocarbons such as carbon tetrachloride, chloroform, methylene chloride, and methyl chloride. The addition amount may vary depending on the chain transfer constant of the compound used, but is usually used in the range of 0.01 to 20% by mass with respect to the polymerization solvent.

Examples of the solvent include water, a mixed solvent of water and alcohol, and the like.

In the suspension polymerization, a fluorine-based solvent may be used in addition to water. Examples of the fluorine-based solvent include hydrochlorofluoroalkanes such as CH ₃ CClF ₂ , CH ₃ CCl ₂ F, CF ₃ CF ₂ CCl ₂ H, CF ₂ ClCF ₂ CFHCl; CF ₂ ClCFClCF ₂ CF ₃ , CF ₃ CFClCFClCF _3, etc. Perfluoroalkanes such as perfluorocyclobutane, CF ₃ CF ₂ CF ₂ CF ₃ , CF ₃ CF ₂ CF ₂ CF ₂ CF ₃ , CF ₃ CF ₂ CF ₂ CF ₂ CF ₂ CF ₃ , etc. Among them, perfluoroalkanes are preferable. The amount of the fluorine-based solvent used is preferably 10 to 100% by mass with respect to the aqueous medium from the viewpoint of suspendability and economy.

It does not specifically limit as polymerization temperature, It may be 0-100 degreeC. The polymerization pressure is appropriately determined according to other polymerization conditions such as the type, amount and vapor pressure of the solvent to be used, the polymerization temperature, etc., but may usually be 0 to 9.8 MPaG.

The fluororesin of the present invention may be in any form, and may be an aqueous dispersion, powder, pellet or the like.

The fluororesin of the present invention can be molded into various molded products, and the resulting molded products are excellent in mechanical strength and chemical resistance at high temperatures, low permeability at high temperatures, and the like.

It does not specifically limit as a shape of the said molded object, For example, a hose, a pipe, a tube, a sheet | seat, a seal, a gasket, packing, a film, a tank, a roller, a bottle, a container etc. may be sufficient.

The molding method of the fluororesin is not particularly limited, and examples thereof include compression molding, extrusion molding, transfer molding, injection molding, lottery molding, lotining molding, and electrostatic coating. When the fluororesin of the present invention is formed into a pipe, extrusion molding is preferred.

In the fluororesin of the present invention, a filler, a plasticizer, a processing aid, a release agent, a pigment, a flame retardant, a lubricant, a light stabilizer, a weather stabilizer, a conductive agent, an antistatic agent, an ultraviolet absorber, and an antioxidant , Foaming agent, fragrance, oil, softening agent, dehydrofluorinating agent and the like may be mixed and then molded. Examples of the filler include polytetrafluoroethylene, mica, silica, talc, celite, clay, titanium oxide, and barium sulfate. Examples of the conductive agent include carbon black. Examples of the plasticizer include dioctyl phthalic acid and pentaerythritol. Examples of processing aids include carnauba wax, sulfone compounds, low molecular weight polyethylene, and fluorine-based aids. Examples of the dehydrofluorinating agent include organic oniums and amidines.

The fluororesin of the present invention can be suitably used for a riser pipe for transporting goods from the sea floor to the sea surface in a seabed oil field or gas field. Further, it can be suitably used as a coating material or lining material for the innermost surface and outermost surface of a fluid transfer metal pipe for crude oil or natural gas, regardless of whether it is underground, on the ground, or on the seabed. The purpose of coating and lining the innermost surface is that crude oil and natural gas contain carbon dioxide and hydrogen sulfide, which cause corrosion of metal pipes. This is to reduce the fluid friction of crude oil of viscosity. The outermost surface is also for suppressing corrosion caused by seawater or acidic water. When lining and coating the innermost surface and outermost surface, in order to further improve the rigidity and strength of the fluororesin of the present invention, glass fiber, carbon fiber, aramid resin, mica, silica, talc, celite, clay, titanium oxide Etc. may be filled. Moreover, in order to make it adhere | attach with a metal, you may perform the process which uses an adhesive agent or roughens the metal surface.
Furthermore, it can be suitably used as a molding material for the following molded articles.

As the molded body, for example,
Fluid transport members for food production equipment such as food packaging films, lining materials for fluid transfer lines used in food manufacturing processes, packing, sealing materials, sheets;
Chemical liquid transfer members such as medicine stoppers, packaging films, lining materials for fluid transfer lines used in chemical manufacturing processes, packing, seal materials, sheets;
Internal lining material for chemical tanks and piping in chemical plants and semiconductor factories;
Fuel transfer members such as O (square) rings, tubes, packings, valve cores, hoses, seals, etc. used in automobile fuel systems and peripheral devices, hoses, seals, etc. used in automobile AT devices;
Car parts such as carburetor flange gaskets, shaft seals, valve stem seals, sealing materials, hoses, etc. used in automobile engines and peripheral devices, and other automobile parts such as automobile brake hoses, air conditioner hoses, radiator hoses, and wire covering materials;
Chemical solution transfer members for semiconductor devices such as O (square) rings, tubes, packings, valve cores, hoses, sealing materials, rolls, gaskets, diaphragms, joints, etc. of semiconductor manufacturing equipment;
Paint and ink components such as paint rolls, hoses, tubes, and ink containers for painting equipment;
Tubes for food and drink or tubes for food and drink, hoses, belts, packings, food and drink transfer members such as joints, food packaging materials, glass cooking equipment;
Waste liquid transport components such as waste liquid transport tubes and hoses;
High temperature liquid transport members such as tubes and hoses for high temperature liquid transport;
Steam piping members such as tubes and hoses for steam piping;
Anticorrosion tape for piping such as tape wrapped around piping of ship decks;
Various coating materials such as an electric wire coating material, an optical fiber coating material, a transparent surface coating material and a back surface agent provided on the light incident side surface of the photovoltaic element of the solar cell;
Sliding members such as diaphragm pump diaphragms and various packings;
Agricultural film, weatherproof covers such as various roof materials and side walls;
Interior materials used in the construction field, glass covering materials such as non-flammable fire safety glass;
Lining materials such as laminated steel sheets used in the field of home appliances;
Etc.

Examples of the fuel transfer member used in the fuel system of the automobile further include a fuel hose, a filler hose, and an evaporation hose. The fuel transfer member can also be used as a fuel transfer member for fuel containing gasoline additives such as for sour gasoline resistant, alcohol resistant fuel, methyl tertiary butyl ether / amine resistant, etc.

The above-mentioned drug stopper / packaging film has excellent chemical resistance against acids and the like. Moreover, the said chemical | medical solution transfer member can also mention the anticorrosion tape wound around chemical plant piping.

Examples of the molded body include a radiator tank, a chemical tank, a bellows, a spacer, a roller, a gasoline tank, a waste liquid transport container, a high temperature liquid transport container, and a fishery / fish farm tank.

As the above molded products, there are also automobile bumpers, door trims, instrument panels, food processing equipment, cooking equipment, water and oil repellent glass, lighting related equipment, display boards / housings for office automation equipment, electric signs, displays, liquid crystals Examples include members used for displays, mobile phones, printed boards, electrical / electronic components, sundries, trash cans, bathtubs, unit baths, ventilation fans, lighting frames, and the like.

A powder coating material comprising the fluororesin is also one aspect of the present invention. The powder coating material may have an average particle size of 10 to 500 μm. The average particle size can be measured using a laser diffraction particle size distribution analyzer. A coating film without foaming marks can be obtained by spraying the powder coating material onto the substrate by electrostatic coating and then baking.

Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

Each numerical value of the examples was measured by the following method.

Using fluorine resin monomer composition nuclear magnetic resonance apparatus AC300 (manufactured by Bruker-Biospin), ¹⁹ F-NMR measurement was performed at a measurement temperature of (polymer melting point + 20) ° C., depending on the integrated value of each peak and the type of monomer. It was determined by combining elemental analysis as appropriate.

Using a melting point differential scanning calorimeter RDC220 (manufactured by Seiko Instruments), heat measurement was performed at a heating rate of 10 ° C./min in accordance with ASTM D-4591, and the melting point was obtained from the peak of the obtained endothermic curve. .

Melt flow rate [MFR]
MFR is based on ASTM D3307-01, and uses a melt indexer (manufactured by Toyo Seiki Co., Ltd.) at a mass of 297 ° C. under a 5 kg load from a nozzle having an inner diameter of 2 mm and a length of 8 mm per 10 minutes. g / 10 min) was defined as MFR.

Thermal decomposition start temperature (1% mass loss temperature)
Using a differential heat / thermogravimetric measuring device (TG-DTA6200 (manufactured by Hitachi High-Tech Science Co., Ltd.)), using fluororesin powder or 10 mg of pellets for measurement, the temperature was raised at 10 ° C./min in an air atmosphere, and 1 mass The temperature at the time of decrease by% was defined as the thermal decomposition start temperature.

Obtaining the number of —CONH ₂ groups (amide groups) of fluororesin Each piece (or pellet) of fluororesin powder (or pellet) was compression molded at room temperature to produce a film having a thickness of 200 μm (± 5 μm). The infrared absorption spectrum analysis of these films was performed. Scanning was performed 128 times using Perkin-Elmer Spectrum Ver3.0, the obtained infrared absorption spectrum was analyzed, and the absorbance of the peak was measured.
The film thickness was measured with a micrometer.
In the obtained infrared absorption spectrum, the absorbance of the peak appearing at 2900 to 3100 cm ⁻¹ due to the CH ₂ group of the main chain was normalized to 1.0.
The absorbance of the peak due to the NH bond of the amide group (—CONH ₂ ) appearing in the vicinity of 3400 to 3470 cm ^{−1 of} the spectrum is determined. The baseline is automatically determined, and the peak height is determined as the peak absorbance A. Using the absorbance A of the peak derived from the amide group (—CONH ₂ ), the number (number) of amide groups per 10 ⁶ carbon atoms is determined by the following formula.
Number of amide groups per 10 ⁶ carbon atoms = K × A
A: Absorbance of peak derived from amide group (—CONH ₂ ) K: Coefficient 4258

In the same manner as the method of determining the absorbance A of a peak derived from the unstable terminal number Determination of amide groups based on the fluorocarbon resin, determined absorbance A of the unstable terminal groups, by the following formula, having 10 per ⁶ carbon Determine the number of each unstable end group.
Number of each unstable terminal group per 10 ⁶ carbon atoms = K × A
A: Absorbance of peak derived from each unstable terminal group K: Coefficient shown in Table 2

The number of unstable terminal groups is calculated by adding the number of each unstable terminal group determined by the above formula.

Comparative Example 1
Distilled water 900 L was charged into a 3000 L autoclave and sufficiently purged with nitrogen. Then, 674 kg of perfluorocyclobutane was charged, and the temperature in the system was maintained at 35 ° C. and a stirring speed of 140 rpm. Subsequently, 207 g of CH ₂ = CHCF ₂ CF ₂ CF ₂ CF ₂ CF ₂ CF _3, 62.0 kg of tetrafluoroethylene (TFE) and 18.1 kg of vinylidene fluoride (VDF) were sequentially charged, and then the polymerization initiator di-n Polymerization was initiated by adding 2.24 kg of 50% by weight methanol solution of propylperoxydicarbonate. Simultaneously with the start of polymerization, 7.0 kg of ethyl acetate was charged. Since the system pressure decreases as the polymerization proceeds, a TFE / VDF mixed gas monomer (TFE / VDF: 60.2 / 39.8 (mol%)) is charged, and CH _{2 is} added to 100 parts of the added mixed gas. = CHCF ₂ CF ₂ CF ₂ CF ₂ CF ₂ CF ₃ was simultaneously charged so as to be 1.21 parts, and the system internal pressure was kept at 0.8 MPa. When the additional charge of the mixed gas monomer finally reached 110 kg, the polymerization was stopped, the pressure was released and the pressure was returned to atmospheric pressure, and then the obtained TFE / VDF / CH ₂ = CHCF ₂ CF ₂ CF ₂ CF _{2 was obtained.} The CF ₂ CF ₃ copolymer was washed with water and dried to obtain 400 kg of powder.

The obtained powder had the following composition and physical properties.
_{TFE / VDF / CH 2 = CHCF} 2 CF 2 CF 2 CF 2 CF 2 CF 3: 59.9 / 39.8 / 0.3 ( mol%)
Melting point: 218 ° C
MFR: 9.0 g / 10 min (297 ° C.-5 kg)

Comparative Examples 2-6
By changing the charged amounts of ethyl acetate as a chain transfer agent and di-n-propyl peroxydicarbonate as a polymerization initiator, a fluororesin having the same composition as Comparative Example 1 but having a different MFR was used. A powder was obtained.
Comparative Example 2 0.5 g / 10 min
Comparative Example 3 1.5 g / 10 min
Comparative Example 4 3.4 g / 10 min
Comparative Example 5 35.0 g / 10 min
Comparative Example 6 80.0 g / 10 min

Comparative Example 7
Distilled water (52.2 L) was charged into a 174 L autoclave and sufficiently purged with nitrogen. Then, 39.1 kg of perfluorocyclobutane was charged, and the temperature in the system was maintained at 35 ° C. and a stirring speed of 200 rpm. Next, 0.34 kg of perfluoro (propyl) vinyl ether, 6.00 kg of TFE, and 1.08 kg of VDF were sequentially added, and then 130 g of a 50 mass% methanol solution of a polymerization initiator di-n-propyl peroxydicarbonate (NPP) was added. The polymerization was started. Simultaneously with the initiation of polymerization, 0.37 kg of ethyl acetate was charged. Since the system pressure decreases as the polymerization proceeds, TFE / VDF mixed gas monomer (TFE / VDF: 65.5 / 34.5 (mol%)) is charged, and perfluoro is added to 100 parts of the added mixed gas. (Propyl) vinyl ether was charged simultaneously to 0.9 part, and the system pressure was kept at 0.9 MPa. When the additional charge of the mixed gas monomer finally reached 8 kg, the polymerization was stopped, and after releasing the pressure to return to atmospheric pressure, the resulting TFE / VDF / perfluoro (propyl) vinyl ether copolymer was washed with water. And dried to obtain 7.5 kg of powder.

The obtained powder had the following composition and physical properties.
TFE / VDF / perfluoro (propyl) vinyl ether: 65.5 / 34.3 / 0.2 (mol%)
Melting point: 228 ° C
MFR: 2.5 g / 10 min (297 ° C.-5 kg)

Comparative Example 8
Distilled water (52.2 L) was charged into a 174 L autoclave and sufficiently purged with nitrogen. Then, 39.1 kg of perfluorocyclobutane was charged, and the temperature in the system was maintained at 35 ° C. and a stirring speed of 200 rpm. Subsequently, 0.34 kg of chlorotrifluoroethylene (CTFE), 5.96 kg of tetrafluoroethylene (TFE) and 0.96 kg of vinylidene fluoride (VDF) were sequentially added, and then a polymerization initiator di-n-propyl peroxydicarbonate. Polymerization was initiated by adding 130 g of a 50 wt% methanol solution of (NPP). Simultaneously with the start of polymerization, 0.40 kg of ethyl acetate was charged. Since the system pressure decreases as the polymerization proceeds, TFE / VDF / CTFE mixed gas monomer (TFE / VDF / CTFE: 64.7 / 32.9 / 2.4 (mol%)) is charged, and the system pressure is reduced. The pressure was kept at 0.9 MPa. When the additional amount of the mixed gas monomer finally reached 8 kg, the polymerization was stopped, and the pressure was released to return to atmospheric pressure. Then, the obtained TFE / VDF / CTFE copolymer was washed with water and dried to obtain 7 .5 kg of powder was obtained.

The obtained powder had the following composition and physical properties.
TFE / VDF / CTFE: 64.9 / 32.7 / 2.4 (mol%)
Melting point: 226 ° C
MFR: 4.5 g / 10 min (297 ° C.-5 kg)

Production of Examples 1 to 8 Each powder obtained in Comparative Examples 1 to 8 was brought into contact with ammonia water to be reacted (amidation treatment). The reaction was carried out so that the number of —CONH ₂ groups became the number shown in Table 3 while changing the concentration of ammonia water, the reaction temperature, and the reaction time.

With respect to the fluororesins obtained in Comparative Examples and Examples, the number of —CONH ₂ groups and unstable terminal groups were determined.

The main unstable terminal groups of Comparative Examples 1-8 and Examples 1-8 are carbonate groups derived from initiators (ROCOO groups). The number of carbonate groups was determined as the total number of unstable terminal groups according to the above-described “How to determine the number of unstable terminal groups of a fluororesin”.
Since the peak derived from the polymer overlaps with the vicinity of the peak due to the carbonate group of Comparative Examples 1 to 8 and Examples 1 to 8 (1780 to 1830 cm ⁻¹ ), a fully amidated polymer was prepared, and the spectrum of the polymer was Take the difference spectrum. The peak (1780 to 1830 cm ⁻¹ ) due to the carbonate group in the difference spectrum is essentially the peak absorbance of the carbonate group. The number of carbonate groups is calculated from the peak absorbance value.
The polymer of Comparative Example 1 was reacted with 1 wt% aqueous ammonia at a reaction temperature of 80 ° C. for 10 hours to obtain a completely amidated polymer. Since the polymer so obtained is fully amidated, there are no unstable initiator-terminated carbonate groups. The obtained polymer had MFR 9.0 g / 10 min, 145 amide groups, and thermal decomposition starting temperature (1% mass loss temperature) of 390 ° C.

Moreover, about the fluororesin obtained by the comparative example and the Example, the thermal decomposition start temperature (1% mass loss temperature) was measured.
The results are shown in Table 4.

Test Example A foaming cup test was performed on the fluororesins obtained in Comparative Examples and Examples.

Method of cup test A sample weight of 10 g was placed in an aluminum cup and placed in a hot air type electric furnace at 300 ° C. for 2 hours.
After 2 hours, the cup was taken out and the state of the resin was visually observed.
The results are shown in Table 5.

Claims (3)

A fluororesin containing vinylidene fluoride units,
-CONH ₂ group at the end of the main chain,
A fluororesin characterized in that the vinylidene fluoride unit is 10.0 to 100 mol% of all monomer units constituting the fluororesin. Further comprising tetrafluoroethylene units,
Vinylidene fluoride units are 10.0 to 70.0 mol% of all monomer units constituting the fluororesin,
The fluororesin according to claim 1, wherein the tetrafluoroethylene unit is 30.0 to 85.0 mol% of all monomer units constituting the fluororesin. And further comprising tetrafluoroethylene units and at least one ethylenically unsaturated monomer unit selected from the group consisting of ethylenically unsaturated monomers represented by formula (1) and formula (2),
The vinylidene fluoride unit is 10.0 to 44.9 mol% of the total monomer units constituting the fluororesin,
Tetrafluoroethylene unit is 50.0-85.0 mol% of all monomer units constituting the fluororesin,
The fluororesin according to claim 1, wherein the ethylenically unsaturated monomer unit is 0.1 to 5.0 mol% of all monomer units constituting the fluororesin.
Formula (1): CX ¹¹ X ¹² = CX ¹³ (CX ¹⁴ X ¹⁵ ) _n11 X ¹⁶
(In the formula, X ^{11 to} X ¹⁶ are the same or different and represent H, F or Cl, and n ¹¹ represents an integer of 0 to 8, except for tetrafluoroethylene and vinylidene fluoride.)
Equation ^{(2): CX 21 X 22} = CX 23 -O (CX 24 X 25) n21 X 26
(Wherein X ^{21 to} X ²⁶ are the same or different and represent H, F or Cl, and n ²¹ represents an integer of 0 to 8)