WO2017018354A1

WO2017018354A1 - Fluorine-containing copolymer composition and molded article

Info

Publication number: WO2017018354A1
Application number: PCT/JP2016/071596
Authority: WO
Inventors: 真和安宅; 海野　正男; 正登志阿部; 定雄兼徳; 渡辺　良二
Original assignee: 旭硝子株式会社
Priority date: 2015-07-28
Filing date: 2016-07-22
Publication date: 2017-02-02
Also published as: JP2018145209A

Abstract

Provided are: a fluorine-containing copolymer composition which is capable of forming a molded article having excellent stiffness at high temperatures and having stress crack resistance at even higher temperatures; and a molded article obtained from the fluorine-containing copolymer composition. This fluorine-containing copolymer composition contains a fluorine-containing copolymer and a copper oxide, and satisfies α₀≥ 10, 0.8 ≤ α₂₄/α₀≤ 1.2, and 0.8 ≤ α₉₆/α₀≤ 1.2, wherein the fluorine-containing copolymer is a specific ethylene/tetrafluoroethylene copolymer. In the above equations, α₀ represents a volume flow rate (in g/10 minutes) of the fluorine-containing copolymer composition under a load of 49 N at 297°C, α₂₄ represents a volume flow rate (in g/10 minutes) of the fluorine-containing copolymer composition under a load of 49 N at 297°C after being heated for 24 hours at 225°C, and α₉₆ represents a volume flow rate (in g/10 minutes) of the fluorine-containing copolymer composition under a load of 49 N at 297°C after being heated for 96 hours at 225°C.

Description

Fluorine-containing copolymer composition and molded article

The present invention relates to a fluorine-containing copolymer composition and a molded body formed by molding the fluorine-containing copolymer composition.

An ethylene / tetrafluoroethylene copolymer (hereinafter also referred to as “ETFE”) is excellent in heat resistance, weather resistance, electrical insulation, non-adhesiveness, water / oil repellency, and the like among fluororesins. It is characterized by high moldability and mechanical strength. Therefore, various molded products such as wire coating, tubes, sheets, films, filaments, pump casings, fittings, packing, linings, coatings, etc., can be obtained by melt molding methods such as extrusion molding, blow molding, injection molding, and rotational molding. It is manufactured.

However, a molded body made of ETFE is inferior in stress crack resistance at a high temperature as compared with a molded body made of other fluororesins such as a tetrafluoroethylene / hexafluoropropylene copolymer.
For example, Patent Document 1 includes a monomer unit based on another monomer in addition to an ethylene unit and a tetrafluoroethylene unit, and the content of each unit is in a specific range. A fluorine-containing copolymer composition in which a small amount of copper oxide is blended with a fluorine copolymer is disclosed. In the examples of Patent Document 1, it is shown that a molded article obtained by molding the fluorine-containing copolymer composition has a stress crack temperature of 197 to 199 ° C. The higher the stress crack temperature, the better the stress crack resistance at high temperatures.

International Publication No. 2013/015202

However, recently, there has been a demand for a fluorine-containing copolymer composition capable of producing a molded article having resistance to stress cracking at a higher temperature. In addition, since the molded article of Patent Document 1 uses a fluorine-containing copolymer having a low melting point, it is excellent in flexibility at high temperature and advantageous in terms of stress crack resistance, but is inferior in rigidity at high temperature, In some cases, the application was limited.

The present invention provides a fluorine-containing copolymer composition capable of forming a molded article having excellent rigidity at high temperatures and having stress crack resistance at higher temperatures, and a molded article of the fluorine-containing copolymer composition With the goal.

As a result of intensive studies on a fluorine-containing copolymer composition containing a fluorine-containing copolymer and copper oxide, the present inventors have specifically controlled the type and content of monomer units constituting the fluorine-containing copolymer. The melting point of the fluorinated copolymer is increased so that the main chain terminal of the fluorinated copolymer does not have a chlorine atom, and the fluorinated copolymer composition satisfies the following formulas (i) to (iii): Then, it discovered that the molded object which was excellent in the rigidity at high temperature, and was equipped with the stress cracking resistance in higher temperature can be shape | molded.

The present invention has the following configuration.
[1] A fluorine-containing copolymer composition containing a fluorine-containing copolymer and copper oxide,
The fluorine-containing copolymer has an ethylene unit, a tetrafluoroethylene unit, and a monomer unit based on a third monomer copolymerizable with ethylene and tetrafluoroethylene, and the main chain terminal has a chlorine atom. Without
The molar ratio of the ethylene unit to the tetrafluoroethylene unit [ethylene unit / tetrafluoroethylene unit] is 44/56 to 50/50, and the third ratio with respect to all the monomer units constituting the fluorine-containing copolymer. The monomer unit content based on the monomer is 1.6 to 2.4 mol%,
The fluorine-containing copolymer composition, wherein the fluorine-containing copolymer composition satisfies the following formulas (i) to (iii):
α ₀ ≧ 10 (i)
0.8 ≦ α ₂₄ / α ₀ ≦ 1.2 (ii)
0.8 ≦ α ₉₆ / α ₀ ≦ 1.2 (iii)
However, the symbol in the said formula means the following.
α ₀ : Capacity flow rate (unit: g / 10 minutes) of the fluorine-containing copolymer composition at 297 ° C. and a load of 49 N.
α ₂₄ : a fluorine-containing copolymer composition obtained by heating a pellet comprising a fluorine-containing copolymer composition having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 24 hours. Capacity flow rate at 297 ° C. and a load of 49 N (unit: g / 10 minutes).
α ₉₆ : A fluorine-containing copolymer composition obtained by heating a pellet comprising a fluorine-containing copolymer composition having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 96 hours. Capacity flow rate at 297 ° C. and a load of 49 N (unit: g / 10 minutes).

[2] The fluorine-containing copolymer composition according to [1], wherein the fluorine-containing copolymer has a hydroxyl group-containing terminal group at the end of the main chain.
[3] The fluorine-containing copolymer composition according to [1] or [2], wherein the third monomer is a compound represented by the following formula.
CH ₂ = CX (CF ₂ ) _n Y
(In the formula, X and Y are each independently a hydrogen atom or a fluorine atom, and n is an integer of 1 to 10.)
[4] The content of the monomer unit based on the third monomer with respect to all monomer units constituting the fluorine-containing copolymer is 1.8 to 2.2 mol%, Any fluorine-containing copolymer composition.
[5] The fluorine-containing copolymer composition according to any one of [1] to [4], wherein the melting point of the fluorine-containing copolymer is 250 ° C. to 265 ° C.
[6] The fluorine-containing copolymer composition according to any one of [1] to [5], wherein the volume flow rate of the fluorine-containing copolymer at 297 ° C. and a load of 49 N is 15 to 40 g / 10 minutes.

[7] The fluorine-containing copolymer composition according to any one of [1] to [6], wherein the copper oxide is cupric oxide.
[8] The fluorine-containing copolymer composition according to any one of [1] to [7], wherein the copper oxide has an average particle size of 0.1 to 10 μm and a BET specific surface area of 5 to 30 m ² / g. .
[9] The fluorine-containing material according to any one of [1] to [8], wherein the content of the copper oxide is 0.00015 to 0.02 parts by mass with respect to 100 parts by mass of the fluorine-containing copolymer. Copolymer composition.
[10] The fluorine-containing copolymer composition according to [9], wherein the content of the copper oxide is 0.0003 to 0.001 parts by mass with respect to 100 parts by mass of the fluorine-containing copolymer.
[11] The fluorine-containing copolymer composition according to any one of [1] to [10], which is a wire coating material.

[12] A molded article obtained by molding the fluorine-containing copolymer composition according to any one of [1] to [11].
[13] A coated electric wire having a coating layer formed from the fluorine-containing copolymer composition of any one of [1] to [11].
[14] The covered electric wire according to [13], wherein the deformation rate represented by the following formula (iv) is 11% or less.
| D ₁ -D ₀ | / D ₀ × 100 (iv)
However, the symbol in a formula means the following.
D ₀ : Diameter of covered electric wire before self-winding [mm]
D ₁ : Maximum diameter [mm] of the wound covered electric wire after self-diameter winding
(However, self-diameter winding means that the covered electric wire is wound around the covered electric wire itself 12 times without a gap. Further, the maximum diameter means the diameter of each winding of the wound covered electric wire by 12 turns. Is the maximum of the diameters obtained and measured.)

According to the present invention, a fluorine-containing copolymer composition capable of forming a molded article having excellent rigidity at high temperatures and resistance to stress cracking at higher temperatures, and a molded article of the fluorine-containing copolymer composition Can provide.

2 is a graph showing the relationship between heating time and α _n / α ₀ when the fluorine-containing copolymer composition of Example 1 and the fluorine-containing copolymer of Comparative Example 1 are heated at 225 ° C., respectively. It is explanatory drawing regarding the measurement of the deformation rate of a covered electric wire.

The fluorine-containing copolymer composition of the present invention contains a fluorine-containing copolymer composed of specific ETFE and copper oxide. Hereinafter, the fluorine-containing copolymer composition of the present invention is also referred to as “composition A”. Further, the fluorine-containing copolymer in the present invention is also referred to as “copolymer A”.

[Fluorine-containing copolymer]
The fluorine-containing copolymer in the present invention (that is, copolymer A) has an ethylene unit, a tetrafluoroethylene unit, and a monomer unit based on a third monomer copolymerizable with ethylene and tetrafluoroethylene. The main chain terminal does not have a chlorine atom.
Hereinafter, the ethylene unit is also referred to as “E unit”. Tetrafluoroethylene is also referred to as “TFE”, and tetrafluoroethylene units are also referred to as “TFE units”. A monomer unit based on the third monomer is also referred to as a “third monomer unit”.

As the third monomer, for example, the general formula CH ₂ = CX (CF ₂ ) _n Y (wherein X and Y are each independently a hydrogen atom or a fluorine atom, and n is an integer of 1 to 10) .). 1 type (s) or 2 or more types can be used for a 3rd monomer.

When a compound represented by the above general formula CH ₂ ═CX (CF ₂ ) _n Y (hereinafter, also referred to as “FAE”) is used as the third monomer, the stress crack resistance of the molded article comprising the composition A is as follows. Is better.
X in the formula is preferably a hydrogen atom. Y in the formula is preferably a fluorine atom.
N in the formula is preferably 2 to 8, and more preferably 2 to 6. If n is more than the said lower limit, the heat resistance of the molded object which consists of a composition A and the stress crack resistance in high temperature will be more excellent. If n is not more than the upper limit of the above range, FAE has sufficient polymerization reactivity. n is particularly preferably 2, 4 or 6.
Preferable specific examples of FAE include CH ₂ ═CH (CF ₂ ) ₂ F, CH ₂ ═CH (CF ₂ ) ₄ F, CH ₂ ═CH (CF ₂ ) ₆ F, CH ₂ ═CF (CF ₂ ) ₄ F, CH ₂ ═CF (CF ₂ ) ₃ H and the like, and in particular, the stress crack resistance of the molded body made of the composition A is more excellent, and CH ₂ ═CH (CF ₂ ) ₄ F (hereinafter, Also referred to as “PFBE”).
One or more FAEs can be used.

The molar ratio [E unit / TFE unit] of the E unit and the TFE unit in the copolymer A is 44.0 / 56.0 to 50.0 / 50.0, and 44.5 / 55.5 to 46. 0.0 / 54.0 is preferred. When the molar ratio is not less than the lower limit of the above range, the melting point of the copolymer A is sufficiently high, the molded product of the composition A is excellent in heat resistance and excellent in rigidity at high temperature. If this molar ratio is below the upper limit of the said range, the molded object of the composition A will be excellent in chemical resistance.

The content of the third monomer unit is preferably 1.6 to 2.4 mol%, and more preferably 1.8 to 2.2 mol% with respect to all monomer units constituting the copolymer A. If the content of the third monomer unit is at least the lower limit of the above range, the molded article of Composition A is excellent in stress crack resistance at high temperatures. When the content of the third monomer unit is not more than the upper limit of the above range, the melting point of the copolymer A is sufficiently high, the molded product of the composition A is excellent in heat resistance and excellent in rigidity at high temperature.

Copolymer A is characterized by having no chlorine atom at the end of the main chain. Since the copolymer A does not have a chlorine atom at the end of the main chain, even if the copolymer A has a specific amount of the above-mentioned specific unit and has a high melting point, As will be described later, the equations (i) to (iii) are easily satisfied. A molded product of the composition A satisfying the formulas (i) to (iii) is excellent in stress crack resistance at higher temperatures.

The copolymer A having no chlorine atom at the end of the main chain can be obtained, for example, by performing a polymerization reaction using an alcohol, hydrocarbon, or hydrofluorocarbon, which will be described later, as a chain transfer agent. Specifically, when an alcohol is used as the chain transfer agent, the hydroxyl group of the alcohol is introduced into the terminal portion of the main chain of the copolymer A, resulting in the copolymer A having a hydroxyl group-containing terminal group at the main chain terminal. . Conversely, for example, when a compound having a chlorine atom such as 1,3-dichloro-1,1,2,2,3-pentafluoropropane (trade name “AK225cb” manufactured by Asahi Glass Co., Ltd.) is used as a chain transfer agent or a polymerization solvent, The polymer A has a chlorine atom-containing terminal group at the main chain terminal.
The terminal group of the copolymer A can be confirmed by analyzing the copolymer A by infrared absorption spectroscopy.

The volume flow rate of the copolymer A at 297 ° C. and a load of 49 N is preferably 15 to 40 g / 10 minutes, and more preferably 20 to 40 g / 10 minutes. When the capacity flow rate of the copolymer A is not less than the lower limit value of the above range, the moldability of the composition A is excellent, and when it is not more than the upper limit value of the above range, the mechanical strength of the molded body of the composition A is high. Excellent resistance to stress cracking.
The volume flow rate of the copolymer A is a measure of the molecular weight, and can be controlled by a method of adjusting the amount of the chain transfer agent when the copolymer A is produced. Moreover, it can adjust also by using together 2 or more types of fluorine-containing copolymers from which volume flow rate differs.

The melting point of the copolymer A is preferably 250 to 265 ° C, more preferably 250 to 260 ° C. When the melting point of the copolymer A is not less than the lower limit of the above range, the molded article of the composition A has excellent heat resistance and excellent rigidity at high temperatures. The moldability of the composition A is excellent when it is not more than the upper limit of the above range.
The melting point of the copolymer A is determined by adjusting the molar ratio of the E unit to the TFE unit [E unit / TFE unit], the content of the third monomer unit with respect to all the units constituting the copolymer A, and the like. Can be controlled.

In the present specification, the melting point is a temperature corresponding to an endothermic peak when the copolymer A is heated by heating at 10 ° C./min in an air atmosphere using a scanning differential thermal analyzer.

The copolymer A can be produced by a known method such as bulk polymerization, solution polymerization, suspension polymerization or emulsion polymerization, and solution polymerization is particularly preferable. For the polymerization, a polymerization initiator, a chain transfer agent, a polymerization medium, or the like can be used.
As the polymerization initiator, a radical polymerization initiator having a half-life of 10 hours and a temperature of 0 to 100 ° C. is preferable, and a radical polymerization initiator having a temperature of 20 to 90 ° C. is more preferable. As specific examples, various polymerization initiators exemplified in Patent Document 1 can be used.
As the polymerization medium, perfluorocarbon, hydrofluorocarbon, hydrofluoroether or the like can be used. As a specific example, for example, the polymerization medium exemplified in Patent Document 1 can be used.

Chain transfer agents have a large chain transfer constant and a small amount of addition, so that methanol, ethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoropropanol, 1,1, Alcohols such as 1,3,3,3-hexafluoroisopropanol and 2,2,3,3,3-pentafluoropropanol; Hydrocarbons such as n-pentane, n-hexane and cyclohexane; CF ₂ H ₂ etc. Preferred are hydrofluorocarbons; ketones such as acetone; mercaptans such as methyl mercaptan; esters such as methyl acetate and ethyl acetate; ethers such as diethyl ether and methyl ethyl ether;
Among them, from the viewpoint of higher chain transfer constant and high stability of the end group of the copolymer A, it is preferably at least one selected from the group consisting of alcohols, hydrocarbons, and hydrofluorocarbons, Alcohols and / or hydrocarbons are more preferable, and alcohols are particularly preferable. Of the alcohols, methanol or ethanol is particularly preferred. Among these, methanol is particularly preferable from the viewpoint of reactivity and availability. One or more chain transfer agents can be used.

The amount of the chain transfer agent used is preferably 0.01 to 50% by mass, more preferably 0.02 to 40% by mass, and 0.05 to 20% by mass based on the total mass of the polymerization medium and the chain transfer agent. Most preferred.

Polymerization conditions are not particularly limited. For example, the polymerization temperature is preferably 0 to 100 ° C, more preferably 20 to 90 ° C. For example, the polymerization pressure is preferably from 0.1 to 10 MPa, more preferably from 0.5 to 3 MPa. The polymerization time is preferably 1 to 30 hours.

[Copper oxide]
As the copper oxide, cuprous oxide and cupric oxide can be used, but cupric oxide is preferable because of excellent stability even in high humidity air.
The copper oxide content is preferably 0.00015 to 0.02 parts by mass, more preferably 0.0003 to 0.001 parts by mass, and 0.0003 to 0.001 parts by mass with respect to 100 parts by mass of the copolymer A. 0007 parts by mass is particularly preferred.
If the copper oxide content is at least the lower limit of the above range, the composition A tends to satisfy the formulas (i) to (iii) as will be described in detail later. A molded product of the composition A satisfying the formulas (i) to (iii) is excellent in stress crack resistance at higher temperatures. If content of copper oxide is below the upper limit of the said range, coloring of the molded object of the composition A will be suppressed.

The average particle diameter of copper oxide is preferably 0.1 to 10 μm, and more preferably 0.5 to 5 μm. BET specific surface area of the copper oxide is preferably 5 ~ 30m ² / g, more preferably 10 ~ ^20m 2 / g. When the average particle size is not more than the upper limit of the above range, or when the BET specific surface area is not less than the lower limit of the above range, cracks starting from copper oxide are unlikely to occur in the molded body of the composition A. Copper oxide having an average particle size of not less than the lower limit of the above range and copper oxide having a BET specific surface area of not more than the upper limit of the above range are easy to produce.

In this specification, an average particle diameter is the value measured using the laser diffraction type particle size distribution measuring apparatus.
In this specification, the BET specific surface area is a value measured by a nitrogen gas adsorption BET method.

[Other ingredients]
The composition A of the present invention may contain components other than the copolymer A and copper oxide in order to develop various properties.
Other components include pigments / dyes, slidability imparting agents, conductivity imparting substances, fiber reinforcing agents, thermal conductivity imparting agents, fillers, polymer materials other than copolymer A, modifiers, crystal nucleating agents. Examples thereof include a foaming agent, a foam nucleating agent, a crosslinking agent, an antioxidant, a light stabilizer, and an ultraviolet absorber. As a specific example, what is illustrated by patent document 1, for example can be used.
The content of other components can be appropriately selected according to the properties to be imparted. 1 type (s) or 2 or more types can be used for another component.

[Fluorine-containing copolymer composition]
The composition A of the present invention satisfies the following formulas (i) to (iii).
α ₀ ≧ 10 (i)
0.8 ≦ α ₂₄ / α ₀ ≦ 1.2 (ii)
0.8 ≦ α ₉₆ / α ₀ ≦ 1.2 (iii)
However, the symbol in the said formula means the following.
α ₀ : Volumetric flow rate of composition A at 297 ° C. and a load of 49 N (unit: g / 10 minutes).
α ₂₄ : Capacity flow rate at 297 ° C. and load of 49 N of composition A after heating a pellet of composition A having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 24 hours (Unit: g / 10 minutes).
α ₉₆ : Capacity flow rate at 297 ° C. and load 49 N of composition A after heating a pellet of composition A having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 96 hours (Unit: g / 10 minutes).

α ₀ is a volume flow rate before heating at 225 ° C. for composition A obtained by melt-kneading copolymer A, copper oxide, and other components used as necessary. is there.
If α ₀ is not less than the lower limit value of the range described in formula (i), the moldability of composition A is excellent, and if it is not more than the upper limit value of the range described in formula (i), composition A The molded article has excellent mechanical strength and stress crack resistance.
In addition, when the composition A has received a certain level of heat history at high temperature, α ₀ tends to be less than the lower limit of the range described in the formula (i).
α ₀ can be controlled by adjusting the volume flow rate of the copolymer A used.

α ₀ preferably satisfies the following formula (ia), and more preferably satisfies the following formula (ib).
10 ≦ α ₀ ≦ 50 (ia)
15 ≦ α ₀ ≦ 35 (ib)

α ₂₄ / α ₀ is 225 ° C. when the composition A was formed into pellets having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm, and the pellets were heated at 225 ° C. for 24 hours. The volume flow rate change rate of the composition A with respect to the capacity | capacitance flow velocity before performing heating by is meant. α ₉₆ / α ₀ is 225 ° C. when the composition A was formed into pellets having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm, and the pellets were heated at 225 ° C. for 96 hours. The volume flow rate change rate of the composition A with respect to the capacity | capacitance flow velocity before performing heating by is meant.
Note that the pellets to be heated only need to have a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm. Within this range, the diameter of the pellets, The lengths may be different from each other.
The molded body of composition A in which α ₂₄ / α ₀ is in the range described in formula (ii) and α ₉₆ / α ₀ is in the range described in formula (iii) The rate of change in the capacity flow rate is small, and the resistance to stress cracking at higher temperatures is excellent.

The inventor examined the stress crack resistance at high temperature of the molded article of the composition A. As a result, the behavior of the capacity flow rate when the composition A was heated at 225 ° C. and the high temperature of the molded article of the composition A were investigated. It has been found that there is a relationship with the stress crack resistance in
Specifically, when the heating time is in the range of 0 to about 24 hours, the capacity flow rate increases remarkably as the heating time elapses, and when the heating time is in the range of about 24 hours to about 96 hours, the heating time is increased. It was found that the molded body of the composition A, in which the capacity flow rate significantly decreases with the passage of time, tends to have insufficient stress crack resistance at high temperatures.
Therefore, the present inventor focused further on the value of the volumetric flow rate α ₂₄ of the composition A when heated for 24 hours and the value of the volumetric flow rate α ₉₆ of the composition A when heated for 96 hours, and further studied. .
As a result, the capacity flow rate change rate when heated for 24 hours, that is, α ₂₄ / α ₀ is in the range described in the formula (ii), and the capacity flow rate change rate when heated for 96 hours, that is, α It was found that the molded article of composition A having ₉₆ / α ₀ in the range described in formula (iii) has excellent stress crack resistance at higher temperatures.

When the heating time is in the range of 0 to about 24 hours, the capacity flow rate increases remarkably as the heating time elapses, and α ₂₄ / α ₀ exceeds the upper limit of the range described in formula (ii), and When the heating time is in the range of about 24 hours to about 96 hours, the capacity flow rate is remarkably lowered with the elapse of the heating time, and α ₉₆ / α ₀ is less than the lower limit value of the range described in the formula (iii) In composition A, the decomposition mainly proceeds when the heating time is in the range of 0 to about 24 hours, and the components generated by the decomposition are crosslinked when the heating time is in the range of about 24 to about 96 hours. It can be inferred that they are equal.
On the other hand, the composition A in which α ₂₄ / α ₀ satisfies the formula (ii) and α ₉₆ / α ₀ satisfies the formula (iii) is hardly decomposed even by heating for a long time. It is considered that crosslinking is difficult. Due to this, it is considered that the molded product of the composition A satisfying the formulas (ii) and (iii) is excellent in stress crack resistance at higher temperatures.
Thus, the capacity flow rate change rate α ₂₄ / α ₀ when heated for 24 hours and the capacity flow rate change rate α ₉₆ / α ₀ when heated for 96 hours are an index of stress crack resistance at high temperatures of the molded body. Become.

α ₂₄ / α ₀ and α ₉₆ / α ₀ may be, for example, introducing a hydroxyl group-containing end group and adding copper oxide using a chain transfer agent composed of an alcohol during the production of the copolymer A. Thus, it can be adjusted to a suitable range. Moreover, (alpha) ₂₄ / (alpha) ₀ and (alpha) ₉₆ / (alpha) ₀ can also be adjusted with the addition amount of a copper oxide.

α ₂₄ / α ₀ preferably satisfies the following formula (ia), and more preferably satisfies the following formula (iib).
α ₉₆ / α ₀ preferably satisfies the following formula (iii).

0.85 ≦ α ₂₄ / α ₀ ≦ 1.0 (iii)
0.9 ≦ α ₂₄ / α ₀ ≦ 1.0 (iib)
0.8 ≦ α ₉₆ / α ₀ ≦ 1.0 (iii)

The composition A can be produced by melt-kneading the copolymer A, copper oxide, and other components used as necessary by a known method. Since the composition A of the present invention is excellent in heat resistance and the thermal deterioration is remarkably suppressed, high temperature molding is possible.
The melt kneading (cylinder temperature of the extruder) is preferably performed under conditions of 250 to 320 ° C. and 30 seconds to 10 minutes.
As described above, the composition A of the present invention can be molded into a molded article having excellent rigidity at high temperatures and excellent stress crack resistance at higher temperatures. Therefore, it is suitably used as a wire covering material for forming a wire covering material that requires heat resistance.

[Molded body]
The molded body of the present invention is obtained by molding the composition A of the present invention described above by a conventionally known molding method such as injection molding, extrusion molding, blow molding, press molding, rotational molding, electrostatic coating, or the like.
Moreover, since the molded object obtained by shape | molding the composition A of this invention is excellent in the rigidity in high temperature and stress crack resistance, (1) Electric machines, such as a robot, an electric motor, a generator, a transformer , Wire covering materials for household electrical equipment, (2) wire covering materials for communication transmission equipment such as telephones and radios, (3) wire covering materials for electronic equipment such as computers, data communication equipment and terminal equipment, (4 ) Railway wire covering material, (5) Automotive wire covering material, (6) Aircraft wire covering material, (7) Ship wire covering material, (8) Building / factory trunk line, power plant, petrochemical / steel manufacturing It can use suitably for the use of the electric wire coating material of various apparatuses, such as the electric wire coating material for system structures, such as a plant.
The molded product of the present invention can also be used for tubes, sheets, films, filaments, pump casings, joints, packing, lining, coating, and the like.

[Coated wire]
The present invention is also a coated electric wire having a coating layer formed from the composition A. The coating layer formed from the composition A is excellent in rigidity at a high temperature and stress crack resistance at a higher temperature. Therefore, the covered electric wire having this covering layer is suitable as a covered electric wire that requires heat resistance.
Examples of the conductor include copper, aluminum, silver, platinum, and gold, and copper is preferable in terms of weight reduction and conductivity. In addition, a hard copper wire and a soft copper wire are used as the copper conductor, and the soft copper wire is particularly preferable in that the conductor has high flexibility and deformation due to stress is reduced.
In addition, the type of twisting of the strands constituting the conductor may be either concentric twisting or collective twisting, but concentric twisting is more preferable because it is difficult to deform when stress is applied.

As the covered electric wire of the present invention, a covered electric wire having a change rate represented by the following formula (iv) of 11% or less is preferable.
| D ₁ -D ₀ | / D ₀ × 100 (iv)
However, the symbol in a formula means the following.
D ₀ : Diameter of covered electric wire before self-winding [mm]
D ₁ : Maximum diameter [mm] of the wound covered electric wire after self-diameter winding
(However, self-diameter winding means that the covered electric wire is wound around the covered electric wire itself 12 times without a gap. Further, the maximum diameter means the diameter of each winding of the wound covered electric wire by 12 turns. Is the maximum of the diameters obtained and measured.)

The self-diameter winding in the measurement of the change rate will be described with reference to FIG.
One bent electric wire having a diameter D ₀ is bent and then the bent portion is fixed, and one side extending from the bent portion is used as the covered electric wire 1 and the other side is used as the covered electric wire 2. While maintaining the diameter D ₀ of the covered electric wire 1, the covered electric wire 2 is wound 12 times so as not to generate a gap around it, thereby obtaining a self-diameter-wrapped covered electric wire 3. In the self-diameter winding covered wires 3, the diameter of each turn of the covered electric wire 2 wound was measured for 12 turns, respectively, the maximum value among the obtained diameter is D _1.
In the stress crack resistance evaluation of the examples, the self-diameter wrapping covered electric wire 3 is produced in the same manner as described above and used as a molded body sample.

When the conductor used is difficult to be deformed by a load or a winding stress, the stress to the molded body used as the coating layer is reduced, and therefore the coated wire is excellent in stress crack resistance. If the deformation rate at the time of self-winding of the covered electric wire increases, the bending radius of the covering layer covered with the conductor becomes small, and the stress applied to the covering layer becomes excessive.
The deformation rate of the covered electric wire is preferably 11% or less, more preferably 7% or less, and further preferably 4% or less. When the upper limit is exceeded, the bending radius of the coating layer to be coated becomes small, and the stress applied to the coating layer becomes excessive, so that the stress crack resistance of the molded body used as the coating layer is deteriorated.

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto.
Various evaluation methods and measurement methods are shown below.

[Analysis of copolymer composition (mol%) and end groups]
The copolymer composition (content of each repeating unit) of the copolymer was calculated from the results of Fourier transform infrared spectrophotometer (FT-IR) measurement.
The terminal group was confirmed by Fourier transform infrared spectrophotometer measurement.

[Average particle size]
The average particle size was measured using a laser diffraction particle size distribution analyzer “HELOS-RODOS” manufactured by Sympatec.

[BET specific surface area]
The BET specific surface area was measured by a nitrogen gas adsorption BET method using “SORPTY-1750” manufactured by Carlo Erba.

[Melting point (° C)]
The melting point of the copolymer was raised to 300 ° C. at 10 ° C./min in an air atmosphere using a scanning differential thermal analyzer (“DSC7020 (trade name)” manufactured by Hitachi High-Tech Science Co., Ltd.). Is the temperature corresponding to the endothermic peak when the is heated.

[Capacity flow rate]
Using a melt flow tester manufactured by Techno Seven, the extrusion speed (g / 10 minutes) when extruding a sample into an orifice having a diameter of 2.1 mm and a length of 8 mm was obtained under the conditions of a temperature of 297 ° C. and a load of 49 N. This was the volume flow rate.
(1) Volume flow rate of copolymer The volume flow rate was measured by the above method.
(2) α ₀
With respect to the obtained compositions (for Comparative Examples 1 and 2, only the copolymer), the volume flow rate α ₀ was measured by the above method.
(3) α ₂₄
The pellets (mass: 5 g, diameter 2.0-3.0 mm, length 2.0-3.0 mm) of the produced composition (comparison only for Comparative Examples 1 and 2) were subjected to a furnace temperature of 225 ° C. In a heating furnace (atmosphere) and kept for 24 hours. Thereafter, the composition was removed from the heating furnace and allowed to cool to room temperature, and then the capacity flow rate α ₂₄ was measured by the above method.
(4) α ₉₆
The pellets (mass: 5 g, diameter 2.0 to 3.0 mm, length 2.0 to 3.0 mm) of the produced composition (for the comparative examples 1 and 2 only the fluorine-containing copolymer) were heated in the furnace. Was placed in a heating furnace (atmosphere) at 225 ° C. and held for 96 hours. Thereafter, the composition was taken out of the heating furnace and allowed to cool to room temperature, and then the volume flow rate α ₉₆ was measured by the above method.

[Stress crack resistance evaluation]
A molded body made of a composition with a coating thickness of 0.5 mm on a 1.8 mm core wire (tin-plated copper stranded wire) in an extruder having a diameter of 30 mm (for Comparative Examples 1 and 2, a molded body made only of a copolymer) .) Was coated.
The conditions are as follows.
Molding temperature: 320 ° C.
DDR (Draw-Down Ratio): 16.
Take-off speed: 10 m / min.
The wire coated as described above was annealed at a predetermined temperature in increments of 5 ° C. for 96 hours. After the annealing treatment, the electric wire was wound around the electric wire itself (self-winding) to prepare a molded body sample. Next, this molded body sample was exposed in a gear oven at 225 ° C. for 1 hour to check for cracks. The number of samples was 5.
Obtain the lowest annealing temperature (T1) at which cracks occur in all five molded body samples and the maximum annealing temperature (T2) at which cracks do not occur in all five molded body samples, and assign these values to the following equation. The stress crack temperature (Tb) was determined.
The stress crack temperature (Tb) is an annealing temperature obtained by the above experiment, at which 50% of the molded body sample is broken. The higher the stress crack temperature, the higher the stress crack resistance. The stress crack temperature is preferably 205 ° C. or higher, and more preferably 210 ° C. or higher.
Tb = T1-ΔT (S / 100-1 / 2)
However, the symbol in the said formula means the following.
Tb: stress crack temperature,
T1: the lowest annealing temperature at which cracks occur in all molded body samples,
ΔT: Annealing temperature interval (5 ° C.),
S: Probability of occurrence of cracks at each temperature from the highest annealing temperature (T2) at which no cracks are generated in all the molded body samples to the lowest annealing temperature (T1) at which cracks are generated in all the molded body samples (for example, five molded sample samples) When cracks occur in two of them, the probability of occurrence is 2/5 = 0.4).

[Deformation rate]
The electric wire covered by the stress crack resistance test was subjected to self-diameter winding 12 times without annealing. The deformation rate was determined from the diameter of the covered electric wire before winding and the maximum value of the diameter of each winding of the wound covered electric wire.

[Example 1]
The polymerization tank with a stirrer with an internal volume of 430 liters was deaerated, and 418.2 kg of CF ₃ (CF ₂ ) ₅ H, 2.12 kg of PFBE, and 3.4 kg of methanol were charged to 66 ° C. while stirring. The temperature was raised, and a mixed gas of TFE / ethylene = 84/16 (mol%) was introduced until the pressure became 1.5 MPaG (gauge pressure), and CF ₃ (CF ₂ ) ₅ H of 50 mass% tert-butylperoxypivalate. A solution in which 26 g of the solution and 4974 g of CF ₃ (CF ₂ ) ₅ H were mixed was injected to initiate polymerization. During the polymerization, a mixed gas of TFE / ethylene = 54/46 (mol%) so that the pressure is 1.5 MPaG, and an amount of PFBE corresponding to 1.9 mol% with respect to 100 mol% of the mixed gas. Was continuously added, and 34 kg of TFE / ethylene mixed gas was charged, and then the autoclave was cooled, the residual gas was purged, and the polymerization was terminated.
The obtained copolymer slurry was transferred to a 850 liter granulation tank, 340 L of water was added and heated with stirring to remove the polymerization medium and residual monomer, and a granulated product was obtained.
The obtained granulated product was dried at 150 ° C. for 5 hours to obtain 34 kg of a granulated product of the copolymer.
Table 1 shows the copolymer composition, melting point, and capacity flow rate of the copolymer obtained. In Table 1, the monomer unit name is indicated by the monomer name, and “Tb” in Table 1 indicates the stress crack temperature.
Further, when the terminal group of the copolymer was confirmed by Fourier transform infrared spectrophotometry, a peak in the vicinity of 3650 cm ⁻¹ due to the hydroxyl group was confirmed.

To 100 parts by mass of the obtained granulated product, 0.00045 parts by mass of cupric oxide (average particle size 0.8 μm, BET specific surface area 12 m ² / g) was added, and an extruder having a diameter of 30 mm was used. Then, melt extrusion was carried out under the conditions of a cylinder temperature of 260 to 300 ° C., a die temperature of 250 ° C., and a screw rotation speed of 30 rpm, to produce pellets of the composition. Hereinafter, the obtained composition is referred to as Composition 1. The compositions and copolymers obtained in the following examples and comparative examples were similarly named.
The obtained pellet was used for covering the electric wire, and stress crack resistance was evaluated by the above method to determine the stress crack temperature.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

FIG. 1 shows a pellet of the composition 1 obtained in Example 1 (mass: 5 g, diameter 2.4 to 2.5 mm, length 2.5 mm) in a heating furnace (atmosphere) having a furnace temperature of 225 ° C. The graph of the rate of change of the volume flow rate when heated for 0 to 96 hours is shown.
The horizontal axis is the heating time (n hours), and the vertical axis is the capacity flow rate change rate (α _n / α ₀ ).
Each plot is data of n = 1 hour, 8 hours, 24 hours, 48 hours, and 96 hours. Further, α ₁ = 26.1 (g / 10 min), α ₈ = 25.2 (g / 10 min), and α ₄₈ = 24.4 (g / 10 min). α ₀ , α _{24 and} α ₉₆ are as described in Table 1.
The capacity flow rate α _n in each heating time was measured by the method described above after the pellet was taken out of the heating furnace and allowed to cool to room temperature.

[Example 2]
A pellet of composition 2 was prepared in the same manner as in Example 1 except that the copolymer produced in Example 1 was used and the addition amount of cupric oxide was changed to 0.00065 parts by mass. Measurements and calculations similar to those of 1 were performed.
The results are shown in Table 1.

[Example 3]
Example except that the amount of PFBE to be continuously added was 2.1 mol% with respect to 100 mol% of the mixed gas of TFE / ethylene = 54/46 (mol%). Polymerization was conducted in the same manner as in No. 1, and the granulated product was dried at 150 ° C. for 5 hours to obtain 34 kg of a granulated product of the copolymer.
Table 1 shows the copolymer composition, melting point, and capacity flow rate of the copolymer obtained.
Further, when the terminal group of the copolymer was confirmed by Fourier transform infrared spectrophotometry, a peak in the vicinity of 3650 cm ⁻¹ due to the hydroxyl group was confirmed.

Except that 0.00045 parts by mass of the same cupric oxide used in Example 1 was added to 100 parts by mass of the obtained granulated product, melt extrusion was performed in the same manner as in Example 1 to obtain a composition. 3 pellets were produced.
Stress crack resistance was evaluated and the stress crack temperature was determined in the same manner as in Example 1 except that the obtained pellet was used.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

[Example 4]
The amount of PFBE added continuously was the same as in Example 1 except that the amount was equivalent to 1.6 mol% with respect to 100 mol% of the mixed gas of TFE / ethylene = 54/46 (mol%). The granulated product was dried at 150 ° C. for 5 hours to obtain 34 kg of a granulated product of the copolymer.
Table 1 shows the copolymer composition, melting point, and capacity flow rate of the copolymer obtained.
Further, when the terminal group of the copolymer was confirmed by Fourier transform infrared spectrophotometer measurement, a peak in the vicinity of 3650 cm ⁻¹ due to the hydroxyl group was confirmed.

Except that 0.00045 parts by mass of the same cupric oxide used in Example 1 was added to 100 parts by mass of the obtained granulated product, melt extrusion was performed in the same manner as in Example 1 to obtain a composition. 4 pellets were produced.
Stress crack resistance was evaluated and the stress crack temperature was determined in the same manner as in Example 1 except that the obtained pellet was used.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

[Example 5]
Polymerization was carried out in the same manner as in Example 1 except that the amount of PFBE continuously added was changed to an amount corresponding to 2.2 mol% with respect to the mixed gas of TFE / ethylene = 54/46 (mol%). The granulated product was dried at 150 ° C. for 5 hours to obtain 34 kg of a granulated product of the copolymer.
Table 1 shows the copolymer composition, melting point, and capacity flow rate of the copolymer obtained.
Further, when the terminal group of the copolymer was confirmed by Fourier transform infrared spectrophotometer measurement, a peak in the vicinity of 3650 cm ⁻¹ due to the hydroxyl group was confirmed.

Except for adding 0.00030 parts by mass of the same cupric oxide as used in Example 1 to 100 parts by mass of the obtained granulated product, melt extrusion was performed in the same manner as in Example 1 to obtain a composition. 5 pellets were produced.
Stress crack resistance was evaluated and the stress crack temperature was determined in the same manner as in Example 1 except that the obtained pellet was used.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

[Example 6]
A pellet of the composition 6 was prepared in the same manner as in Example 5 except that the amount of cupric oxide added was changed to 0.001 part by mass using the copolymer produced in Example 5. Measurements and calculations similar to those of 1 were performed.
The results are shown in Table 1.

[Example 7]
A pellet of the composition 7 was prepared in the same manner as in Example 5 except that the amount of cupric oxide added was changed to 0.0015 parts by mass using the copolymer produced in Example 5. Measurements and calculations similar to those of 1 were performed.
The results are shown in Table 1.

[Example 8]
A pellet of composition 8 was prepared in the same manner as in Example 5 except that the amount of cupric oxide added was changed to 0.0020 parts by mass using the copolymer produced in Example 5. Measurements and calculations similar to those of 1 were performed.
The results are shown in Table 1.

[Comparative Example 1]
Using the copolymer produced in Example 5, except that cupric oxide was not added, pellets of copolymer 9 were prepared in the same manner as in Example 1, and the same measurements and calculations as in Example 1 were performed. went.
The results are shown in Table 1.
In FIG. 1, the pellets of the copolymer 9 of Comparative Example 1 (mass: 5 g, diameter 2.4 to 2.6 mm, length 2.5 mm) are placed in a heating furnace (atmosphere) having a furnace temperature of 225 ° C. The graph of the volume flow rate change rate when heated for 0 to 96 hours is shown.
The horizontal axis is the heating time (n hours), and the vertical axis is the capacity flow rate change rate (α _n / α ₀ ).
Each plot is data of n = 1 hour, 8 hours, 24 hours, 48 hours, and 96 hours. Α ₁ = 34.3 (g / 10 min), α ₈ = 36.2 (g / 10 min), and α ₄₈ = 18.1 (g / 10 min). α ₀ , α _{24 and} α ₉₆ are as described in Table 1.
The capacity flow rate α _n in each heating time was measured by the method described above after the pellet was taken out of the heating furnace and allowed to cool to room temperature.

[Comparative Example 2]
A polymerization tank equipped with a stirrer with an internal volume of 94 liters was degassed, and 63.1 kg of 1-hydrotridecafluorohexane and 1,3-dichloro-1,1,2,2,3- 42.1 kg of pentafluoropropane (trade name “AK225cb” manufactured by Asahi Glass Co., Ltd., hereinafter referred to as “AK225cb”) and 0.7 kg of PFBE were charged, and 13.9 kg of TFE and 0.5 kg of ethylene were injected. .
The temperature in the polymerization tank was raised to 66 ° C., and 460 mL of a 1% by mass AK225cb solution of tertiary butyl peroxypivalate (hereinafter referred to as “PBPV”) was charged as a polymerization initiator solution to initiate polymerization.
During the polymerization, a monomer mixed gas having a molar ratio of TFE / ethylene = 60/40 was continuously charged so that the pressure was constant. Further, in accordance with the charging of the monomer mixed gas, an amount of PFBE corresponding to 2.0 mol% with respect to the total number of moles of TFE and ethylene was continuously charged.
6.0 hours after the start of polymerization, when 7.4 kg of the monomer mixed gas was charged, the temperature inside the polymerization tank was lowered to room temperature, and the pressure in the polymerization tank was purged to normal pressure.
The obtained copolymer slurry was put into a 220 L (liter) granulation tank charged with 77 kg of water, and then granulated while distilling and removing the solvent by raising the temperature to 105 ° C. while stirring. The obtained granulated product was dried at 150 ° C. for 5 hours to obtain 7.3 kg of a granulated product of the copolymer.
Table 1 shows the copolymer composition, melting point, and capacity flow rate of the copolymer obtained.
Further, when the terminal group of the copolymer was confirmed by Fourier transform infrared spectrophotometer measurement, a chlorine group could be confirmed, and a hydroxyl group could not be confirmed.

The obtained granulated material was melt-extruded with an extruder having a caliber of 30 mm under the conditions of a cylinder temperature of 260 to 300 ° C., a die temperature of 250 ° C., and a screw rotation speed of 30 rpm, and a pellet of the copolymer 10 was produced. .
Stress crack resistance was evaluated and the stress crack temperature was determined in the same manner as in Example 1 except that the obtained pellet was used.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

[Comparative Example 3]
Melt extrusion was performed in the same manner as in Example 1 except that 0.0005 parts by mass of the same cupric oxide used in Example 1 was added to 100 parts by mass of the granulated product obtained in Comparative Example 2. The pellet of the composition 11 was produced.
Stress crack resistance was evaluated and the stress crack temperature was determined in the same manner as in Example 1 except that the obtained pellet was used.
Further, α ₀ , α ₂₄ , and α ₉₆ were measured by the above method, and α ₂₄ / α ₀ and α ₉₆ / α ₀ were calculated.
The results are shown in Table 1.

The molded body of each example had a stress crack temperature of 208 ° C. or higher, and it was revealed that the stress crack resistance at high temperatures was excellent.
In particular, the molded body of Example 2 in which the values of α ₂₄ / α ₀ and α ₉₆ / α ₀ are in a more preferable range has a stress crack temperature of 216 ° C., and the stress crack resistance at high temperatures is extremely high. It was excellent.
Moreover, it turned out that the stress crack temperature also improves from the result of Example 1, Example 2, and Comparative Example 1. Specifically, the stress crack temperature was improved by 29 ° C. in Comparative Example 1 in Example 1 and improved by 31 ° C. in Comparative Example 1 in Comparative Example 1.
On the other hand, from the results of Comparative Example 2 and Comparative Example 3, the molar ratio of the repeating unit (a1) to the repeating unit (a2) is out of a specific range, and the copolymer does not have a hydroxyl group-containing end group. Although cupric oxide was added, the stress crack temperature was improved only by 13 ° C., and the stress crack resistance at high temperature was insufficient.

[Examples 9 to 17, Comparative Examples 4 to 6]
The deformation rate was measured using the covered electric wires covered with the molded products of the compositions and copolymers of Examples 1 to 8 and Comparative Examples 1 to 3. The results are shown in Table 2. Moreover, it measured similarly about the covered electric wire which changed the kind of conductor using the molded object which consists of the compositions 2.
In Table 2, the conductor 1 is an element wire diameter of 0.26 mm, the number of element wires of 37, a conductor diameter of 1.8 mm, and a concentric twisted copper conductor. The conductor 2 is a copper conductor having a strand diameter of 0.25 mm, a number of strands of 50, a conductor diameter of 1.8 mm, and a collective twist.
By making the conductor concentric twist, it is considered that the deformation rate is lower than that of the collective twist and the stress crack resistance is further improved.

The composition A of the present invention can produce a molded article having superior stress crack resistance at a higher temperature than conventional.
Therefore, the molded body of the present invention is particularly suitable for (1) electric machines such as robots, electric motors, generators and transformers, wire covering materials for household electric appliances, and (2) communication transmission equipment such as telephones and radios. (3) Wire covering material for electronic equipment such as computer, data communication equipment and terminal equipment, (4) Railway wire covering material, (5) Automotive wire covering material, (6) Aircraft wire Suitable for use as a wire covering material for various devices, such as covering materials, (7) wire covering materials for ships, (8) wire covering materials for system construction of buildings / factory trunk lines, power plants, petrochemical / steel plants, etc. Can be used.
The entire contents of the specification, claims, abstract, and drawings of Japanese Patent Application No. 2015-148486 filed on July 28, 2015 are cited here as disclosure of the specification of the present invention. Incorporated.

Claims

A fluorine-containing copolymer composition containing a fluorine-containing copolymer and copper oxide,
The fluorine-containing copolymer has an ethylene unit, a tetrafluoroethylene unit, and a monomer unit based on a third monomer copolymerizable with ethylene and tetrafluoroethylene, and the main chain terminal has a chlorine atom. Without
The molar ratio of the ethylene unit to the tetrafluoroethylene unit [ethylene unit / tetrafluoroethylene unit] is 44/56 to 50/50, and the third ratio with respect to all the monomer units constituting the fluorine-containing copolymer. The monomer unit content based on the monomer is 1.6 to 2.4 mol%,
The fluorine-containing copolymer composition, wherein the fluorine-containing copolymer composition satisfies the following formulas (i) to (iii):
α 0 ≧ 10 (i)
0.8 ≦ α 24 / α 0 ≦ 1.2 (ii)
0.8 ≦ α 96 / α 0 ≦ 1.2 (iii)
However, the symbol in the said formula means the following.
α 0 : Capacity flow rate (unit: g / 10 minutes) of the fluorine-containing copolymer composition at 297 ° C. and a load of 49 N.
α 24 : a fluorine-containing copolymer composition obtained by heating a pellet comprising a fluorine-containing copolymer composition having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 24 hours. Capacity flow rate at 297 ° C. and a load of 49 N (unit: g / 10 minutes).
α 96 : A fluorine-containing copolymer composition obtained by heating a pellet comprising a fluorine-containing copolymer composition having a diameter of 2.0 to 3.0 mm and a length of 2.0 to 3.0 mm at 225 ° C. for 96 hours. Capacity flow rate at 297 ° C. and a load of 49 N (unit: g / 10 minutes).
The fluorine-containing copolymer composition according to claim 1, wherein the fluorine-containing copolymer has a hydroxyl group-containing terminal group at the end of the main chain.
The fluorine-containing copolymer composition according to claim 1 or 2, wherein the third monomer is a compound represented by the following formula.
CH 2 = CX (CF 2 ) n Y
(In the formula, X and Y are each independently a hydrogen atom or a fluorine atom, and n is an integer of 1 to 10.)
The content of the monomer unit based on the third monomer with respect to all the monomer units constituting the fluorine-containing copolymer is 1.8 to 2.2 mol%, according to any one of claims 1 to 3. The fluorine-containing copolymer composition described.
The fluorine-containing copolymer composition according to any one of claims 1 to 4, wherein the melting point of the fluorine-containing copolymer is 250 ° C to 265 ° C.
The fluorine-containing copolymer composition according to any one of claims 1 to 5, wherein the fluorine-containing copolymer has a volume flow rate of 15 to 40 g / 10 minutes at 297 ° C and a load of 49 N.
The fluorine-containing copolymer composition according to any one of claims 1 to 6, wherein the copper oxide is cupric oxide.
The fluorine-containing copolymer composition according to any one of claims 1 to 7, wherein the copper oxide has an average particle size of 0.1 to 10 µm and a BET specific surface area of 5 to 30 m 2 / g.
The fluorine-containing copolymer according to any one of claims 1 to 8, wherein a content of the copper oxide is 0.00015 to 0.02 parts by mass with respect to 100 parts by mass of the fluorine-containing copolymer. Polymer composition.
The fluorine-containing copolymer composition according to claim 9, wherein the content of the copper oxide is 0.0003 to 0.001 parts by mass with respect to 100 parts by mass of the fluorine-containing copolymer.
The fluorine-containing copolymer composition according to any one of claims 1 to 10, which is a wire coating material.
A molded product obtained by molding the fluorine-containing copolymer composition according to any one of claims 1 to 11.
A coated electric wire having a coating layer formed from the fluorine-containing copolymer composition according to any one of claims 1 to 11.
The covered electric wire according to claim 13, wherein the deformation rate represented by the following formula (iv) is 11% or less.
| D 1 -D 0 | / D 0 × 100 (iv)
However, the symbol in a formula means the following.
D 0 : Diameter of covered electric wire before self-winding [mm]
D 1 : Maximum diameter [mm] of the wound covered electric wire after self-diameter winding
(However, self-diameter winding means that the covered electric wire is wound around the covered electric wire itself 12 times without a gap. Further, the maximum diameter means the diameter of each winding of the wound covered electric wire by 12 turns. Is the maximum of the diameters obtained and measured.)