JPH041238A - Polyetherketone copolymer film - Google Patents

Abstract

PURPOSE:To improve heat resistance and dimensional stability by thermally treating a specific polyetherketone copolymer film twice under specific conditions. CONSTITUTION:A reaction product obtd. by reacting a dihalogenobenzonitrile, 4,4'-biphenol, and an alkali metal compd. (e.g. Na2CO3) in the presence of a neutral polar solvent is copolymerized with a 4,4'-dihalogenobenzophenol to give a polyetherketone copolymer comprising repeating units of formulas I and II and having a molar ratio of the repeating units of formula I to those of formula I and formula II of 0.15-0.40 and a melt viscosity at 40 deg.C of 3000-100000cPs. The copolymer is formed into a film, which is stretched monoaxially or biaxially in a stretching ratio of 1.5-10, thermally treated at a temp. between the crystallizing temp. and crystalline melting temp. (190-370 deg.C) for 1-600sec, and thermally treated again at a temp. between the glass transition temp. and crystalline-melting temp. (above 150 deg.C and below the temp. of the first thermal treatment) for 1-600sec.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a novel polyetherketone copolymer film, and more specifically, it relates to a novel polyetherketone copolymer film that has high heat resistance and excellent dimensional stability at high temperatures, such as This invention relates to a polyetherketone copolymer film that can be widely used in various applications in the electrical and electronic fields.

[Prior art and invention or problem to be solved] In recent years, in order to develop materials with excellent heat resistance, mechanical properties, and dimensional accuracy,
Various films such as polyamide, polyimide, polyester, and polysulfone have been developed or are already commercially available.
These materials are used for a wide range of purposes as materials for parts of electronic and electrical equipment and machinery.

Among these, aromatic ether ketone copolymers are materials with excellent heat resistance, flame retardance, and chemical resistance, and films are also used as heat-resistant flexible prints as electrical insulating materials in the electrical and electronic fields. Its application as a circuit base material is expected.

However, among these resin films, no film has been found that fully satisfies properties such as heat resistance, mechanical properties, and dimensional accuracy.

Among the resin films currently used, even polyetherketone resin, a thermoplastic resin film that is said to have the best performance, has a low glass transition temperature and insufficient heat resistance for practical use. be.

The present invention has been made based on the above circumstances.

An object of the present invention is to provide a thermoplastic resin film that has high heat resistance, less heat shrinkage at high temperatures, and excellent dimensional accuracy.

[Means for Solving the Problem] To achieve the above object, the invention according to claim 1 comprises a repeating unit represented by the following formula (1); and a repeating unit represented by the following formula (■): (II) composition ratio of repeating units represented by m description (I) [molar ratio, (1)/((I)
+(II))] or 0.15 to 0.40, and
Melt viscosity (zero shear viscosity) at a temperature of 400°C is 3,
A film of a polyetherketone copolymer having a void of 000 to 1G0,000 is heat-treated at a temperature between the crystallization temperature and the crystal melting point of the polyetherketone copolymer, and the heat-treated film is A polyetherketone copolymer film obtained by reheating the polyetherketone copolymer at a temperature between the glass transition temperature and the crystal melting point of the polyetherketone copolymer; An ether ketone copolymer film is stretched in a uniaxial or biaxial direction at a stretching ratio of 1.5 to 10 times, and the stretched film is stretched between the crystallization temperature and crystal melting point of the polyether ketone copolymer. This is a polyetherketone copolymer film obtained by heat-treating the polyetherketone copolymer at a temperature and then heat-treating the heat-treated stretched film at a temperature between the glass transition temperature and crystal melting point of the polyetherketone copolymer.

This will be explained in detail below.

Polyetherketone copolymer - One of the important points in the boetherketone copolymer film of the present invention is that the polyetherketone copolymer or the repeating unit represented by formula (I) and the It consists of a repeating unit represented by formula (n), and
The composition ratio (mole ratio) of the repeating unit represented by the formula (I) is in the range of 0.15 to 0.40, and the composition ratio (mole ratio) of the repeating unit represented by the formula (Ir) is 0.85.
~0.60.

The composition ratio of the repeating unit represented by the formula (I) is 0.
If it is less than 15, the glass transition temperature of the polyetherketone copolymer will be low, resulting in a decrease in heat resistance, or the melting point will be high, leading to a decrease in moldability. On the other hand, 0.4
When it exceeds 0, the crystallinity of the polyetherketone copolymer is lost, resulting in a decrease in heat resistance and solvent resistance.

Further, in the polyetherketone copolymer of the present invention, it is important that the melt viscosity (zero shear viscosity) at a temperature of 400°C is 3,000 to 100,000 voids.

This is because a low molecular weight polyetherketone copolymer having a melt viscosity of less than 3,000 voids cannot achieve sufficient heat resistance and mechanical strength.

Furthermore, if the melt viscosity exceeds 100,000 voids, it becomes difficult to form a film.

The polyetherketone copolymer used in the present invention is
Melt viscosity at 400°C is 3,000 to 100.00
0 voids, its crystal melting point is about 330 to 400°C, it has high crystallinity, has a sufficiently high molecular weight, shows sufficient heat resistance, and has good solvent resistance.
It has excellent mechanical strength and can be suitably used as a new material in the electrical/electronic equipment field, mechanical field, etc.

Such a polyetherketone copolymer can be produced as follows.

-Production method of polyetherketone copolymer-The polyetherketone copolymer is prepared by mixing dihalogenobenzonitrile, 4,4"-biphenol, and an alkali metal compound in a specific usage ratio in the presence of a neutral polar solvent. It can be produced by copolymerizing the reaction product with a specific amount of 4,4°-dihalogenobenzophenone.

Specific examples of the dihalogenobenzonitrile that can be used include 2,6-dihalogenobenzonitrile represented by the following formula: (wherein, X is a halogen atom); , 4-dihalogenobenzonitrile and the like.

Among these, preferred are 2,6-dichlorobenzonitrile, 2,6-difluorobenzonitrile, and 2.4-dichlorobenzonitrile.
2.6-dichlorobenzonitrile is particularly preferred.

In the method of the present invention, the dihalogenobenzonitrile and 4,4'-biphenol are reacted in the presence of an alkali metal compound and a neutral polar solvent.

The alkali metal compound to be used is as described in 4.4 above.
It may be any salt that can convert '-biphenol into an alkali metal salt, and there are no particular limitations, but alkali metal carbonates and alkali metal hydrogen carbonates are preferred.

Examples of the alkali metal carbonates include lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate,
Examples include cesium carbonate.

Among these, preferred are sodium carbonate and potassium carbonate.

Examples of the alkali metal hydrogen carbonate include lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate,
Examples include rubidium hydrogen carbonate and cesium hydrogen carbonate.

Among these, preferred are sodium hydrogen carbonate and potassium hydrogen carbonate.

In the method of the present invention, among the various alkali metal compounds mentioned above, sodium carbonate and potassium carbonate can be particularly preferably used.

Examples of the neutral polar solvent include N,N-dimethylformamide, N,N-diethylformamide, N,N
-dimethylacetamide, N.

N-diethylacetamide, N,N-diethylacetamide, N,N-dimethylbenzoic acid amide, N-methyl-
2-pyrrolidone, N-ethyl-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-isobutyl-2-pyrrolidone, N-n-propyl-2-pyrrolidone, N-n
-butyl-2-pyrrolidone, N-cyclohexyl-2-
Pyrrolidone, N-methyl-3-methyl-2-pyrrolidone, N-ethyl-3-methyl-2-pyrrolidone, N-methyl-3.4.5-trimethyl-2-pyrrolidone, N-methyl-2-piperidone, N -ethyl-2-piperidone,
N-isopropyl-2-piperidone, N-methyl-6-
Methyl-2-piperidone, N-methyl-3-ethylpiperitone, dimethyl sulfoxide, diethyl sulfoxide, l-methyl-1-oxosulfolane, 1-ethyl-1
-oxosulfolane, 1-phenyl-1-oxosulfolane, N,N'-dimethylimidazolidinone, diphenylsulfone, and the like.

In the present invention, the reaction product obtained by reacting the dihalogenobenzonitrile with the 4,4'-biphenol in the presence of the alkali metal compound 8 and the neutral polar solvent and the 4.4 °-Dihalogenobenzophenone is reacted. Alternatively, these raw materials can be added and reacted at the same time.

The 4,4'-dihalogenobenzophenone used is a compound represented by the following linear formula: (where X has the same meaning as above), and in the method of the present invention, 4. 4'-difluorobenzophenone and 4,4'-dichlorobenzophenone are particularly preferably used.

The molar ratio of the total amount of 2,6-dihalogenobenzonitrile and 4.4°-dihalogenobenzophenone to the amount of 4,4'-biphenol used in the production of the polyetherketone copolymer of the present invention? , usually 0.98~
1.02, preferably 1.00 to 1.01. The molar ratio to potassium carbonate 4,4°-biphenol is 1
Usually 1.03 to 2.50, preferably 1.05 to 1
．． It is 25.

There is no particular restriction on the amount of the neutral polar solvent used, but it is usually the same amount as the dihalogenobenzonitrile and 4.
The amount is selected from 200 to z,ooo parts by weight per 100 parts by weight of the 4'-biphenol and the alkali metal compound.

To obtain a polyetherketone copolymer, for example,
The dihalogenobenzonitrile, the 4,4°-biphenol, and the alkali metal compound are simultaneously added to the neutral polar solvent to form the dihalogenobenzonitrile, the 4°4′-biphenol, and the phenol. After the reaction with 4,4-dihalogenobenzophenone is further added, the temperature is usually 150 to 380°C, preferably 18°C.
A series of reactions is carried out at a temperature in the range of 0 to 330°C.If the reaction temperature is less than 150°C, the reaction rate is too slow to be practical, and if it exceeds 380°C, side reactions may occur.

In addition, the reaction time of this series of reactions is usually 0.1 to 1
0 hours, preferably 1 hour to 5 hours.

After the reaction is completed, the polyetherketone copolymer is separated and purified from the resulting neutral polar solvent solution containing the polyetherketone copolymer according to a known method. You can also obtain union.

-Method for producing a polyetherketone copolymer film- The polyetherketone copolymer film according to claim 1 is produced by forming the polyetherketone copolymer into a film, heat treating the film, and then reheating the film. It can be obtained by

By forming the polyetherketone copolymer obtained as described above into a film, an unstretched film of the polyetherketone copolymer can be obtained.

fill!・The conversion is carried out at a temperature of 10 to 100 °C higher than the crystal melting point, preferably 30 to 70 °C higher than the crystal melting point, using a conventional method such as an extrusion molding method or a press molding method, followed by rapid cooling. By this, a non-quality film with good transparency can be obtained.

For example, by supplying the polyetherketone copolymer to an extruder, setting the temperature of the polyetherketone copolymer to 350 to 400°C, extruding it through a slit-shaped die in a molten state, and cooling and solidifying it, It is possible to produce an unstretched film of a polyetherketone copolymer.

Or press at a temperature of 350 to 450 using a heat press machine.
By forming a press film at °C and then rapidly cooling it, an unstretched film of the polyetherketone copolymer can be obtained.

Next, a crystalline film can be obtained by heat-treating the non-quality film thus obtained at a temperature between its crystallization temperature and crystal melting point.

- The heat treatment of the unstretched film is carried out under tension, and the polyether is heated to a temperature higher than the crystallization temperature, that is, the temperature at which the polymer in the amorphous state crystallizes after forming into a film, but lower than the crystal melting point. This is achieved by heating the ketone copolymer.

Under tension in the heat treatment of the present invention means that when the polyetherketone copolymer film is fixed at the foot length and heat treated,
This refers to applying tension caused by shrinkage of the film due to this heat treatment. Specifically, it refers to applying the tension to an unstretched polyetherketone copolymer film by fixing it to a metal frame or the like.

The heat treatment temperature is, for example, 190 to 370°C, and the heat treatment time is 1 to 600 seconds.

Examples of the heating method for the heat treatment include a method of passing the material through a heating furnace and a method of sandwiching it between heating rolls.

Next, the crystallized film obtained by the heat treatment is heat treated again.

This reheat treatment is carried out under tension or without tension as required, and is carried out at a temperature between the glass transition temperature and crystal melting point of the polyetherketone copolymer.

For example, further heat treatment is performed in a relaxed state at a temperature of 150°C or higher and lower than the heat treatment temperature, or 20%
Further heat treatment is performed under limited shrinkage or leg length or slight elongation.

The reheat treatment time is 1 to 600 seconds.

This reheat treatment reduces the heat shrinkage rate of the film, making it possible to obtain a film with excellent dimensional stability.

In the present invention, the polyetherketone copolymer film to be subjected to the heat treatment is an unstretched film;
The polyetherketone copolymer film to be subjected to the heat treatment is a stretched film.

Stretching of polyetherketone copolymer film is -
It is preferable to perform the film axially or biaxially at a temperature between the glass transition temperature and the crystal melting point. In the present invention, the polyetherketone copolymer film is stretched at a stretching ratio of 1.5.
It is preferable to stretch at ~10 times, especially at a stretching ratio of 2~10 times.
It is preferable to stretch the film by a factor of 5.

If the stretching ratio is less than 1.5 times, a sufficient stretching effect (improving effect on film properties such as tensile strength and tensile modulus) may not be achieved, and even if the stretching ratio exceeds 10 times, the stretching The effect may not improve further.

In the invention according to claim 2, the stretched film of the polyetherketone copolymer thus obtained is subjected to heat treatment and reheat treatment.

The operations, conditions, etc. of the heat treatment and reheat treatment are the same as described for the invention according to claim 1 above.

The polyetherketone copolymer film according to claims 1 and 2 is used in the electronics field as a base film for flexible printed circuit boards, a backing material for flexible printed circuit boards, an electrode plate for membranes, a backing material for membranes, and a transparent It can be used for electrode base films, liquid crystal film cells, IC carrier tapes, optical cards, perpendicular magnetization base films, etc. (2) In the electrical and thermal insulation fields.

Planar heating element bases and surface cover films, insulating tapes (motors, generators, transformers), capacitors, wire coatings, microwave ovens, and other heat si! Can be used for li shielding plates, speaker diaphragms, lighting equipment covers, instrument display panels, etc. (3) In general industrial applications, overhead projector base paper, aircraft interior materials, nuclear power related equipment, solar collector covers. , ultrafiltration membranes, etc.

(4) In addition, it can be used for heat-resistant labels, heat-resistant nameplates, and composites related to aviation, vehicles, defense, etc.

[Examples] Next, the present invention will be described in more detail based on Examples.

(Example 1) 1,548 g of 2,6-cyclopenzonitrile was placed in a reactor with an internal volume of 200 g, equipped with a Dean-Starck trap filled with toluene, a stirring device, and an argon gas blowing tube.
g (9 mol), 4.4°-biphenol 5,580
g (30 mol), potassium carbonate 4.561 g (
33 moles) and 50 moles of N-methylpyrrolidone,
While blowing argon gas, it took 1 hour to warm up to room temperature.
The temperature was raised to 195°C.

After raising the temperature, a small amount of toluene was added and the produced water was removed by azeotropy.

Next, after reacting for 30 minutes at a temperature of 195°C, 4,582 g of 4,4'-difluorobenzophenone (
A solution of 21 mol) dissolved in 70 moles of N-methylpyrrolidone was added, and the reaction was further carried out for 1 hour.

After the reaction was completed, the product was pulverized using a blender (manufactured by Warning Co., Ltd.), washed with water and methanol in that order, and then dried to obtain 10.0 kg of white powder (yield: 98%).

When the properties of this powdered product were measured, the melt viscosity (zero shear viscosity) at a temperature of 400°C was 13.0.
00 voids, glass transition temperature 185°C, crystal melting point 379°C1 crystallization temperature 250°C1 thermal decomposition start temperature 5
62°C (5% weight loss in air).

Further, according to IR spectrum analysis, this powdered product was found to be a polyetherketone copolymer having the following repeating units.

(n) (I)/((I)+(II)) = 0.3 Next, this polyetherketone copolymer was heated to 390 It was extruded at 0.degree. C. and then pelletized.

This pellet was extruded into a film with a diameter of 25 cm using a T-die.

The obtained film was fixed with a metal frame and placed under tension for 3
Heat treatment was performed at 00°C for 180 seconds. The resulting heat-treated film had a wall thickness of 1001 bm, and its mechanical strength was as follows.

Tensile strength (ASTII D882) 9.5kg/
sm” tensile modulus (ASTII D882) 27
0kg/1m■2 Breaking elongation (ASTM D882)
50%, then the heat-treated film obtained here was fixed at foot length and reheated at 250° C. for 180 seconds.

Regarding the reheat-treated film obtained in this way, when the film was kept at 200°C for 30 minutes in a relaxed state, and
The heat shrinkage rate when held at 0° C. for 30 minutes was measured.

The results were as follows.

Hold at 200℃ for 30 minutes 0.10% 250℃
, held for 30 minutes 0.08% or more results are summarized in Table 1.

(Example 2) The heat-treated film obtained in Example 1 above was subjected to reheat treatment at 200° C. for 300 seconds in a relaxed state.

Regarding the reheat-treated film obtained in this way, when held at 200 °C for 30 minutes in a relaxed state, and 25
The heat shrinkage rate when held at 0° C. for 30 minutes was measured.

The results were as follows.

Hold at 200℃ for 30 minutes 0.15% 250℃
, held for 30 minutes 0.20% (Comparative Example 1) In Example 2, the heat shrinkage rate measured for the film before being reheated was as follows.

Hold at 200℃ for 30 minutes 0.75% 250℃
, held for 30 minutes 0.95% The results are shown in Table 1.

(Example 3) The amount of raw materials charged during copolymer production in Example 1 was changed to 2-
6-Cyclohenzonite! Jul 1290g (7゜5mol), potassium carbonate 4976g (36mol), 4゜4
'-Difluorobenzophenone 4910g (22,5
A polyetherketone copolymer having the following structure was produced in the same manner as in Example 1, except that the amount was changed to (mol).

(II) (I) / ((II) + (II)) = 0.25 This polyetherketone copolymer has a melt viscosity (zero shear viscosity) of 4 D [1” C of 3 of 15.0 (l[l poise, glass transition temperature is 182℃, melting point is 380℃
The crystallization temperature was 241°C, and the thermal decomposition initiation temperature was 562°C.

Then, this copolymer was extruded into a film in the same manner as in Example 1, and heat treated to obtain a heat treated film with a wall thickness of 10 DILm. The mechanical strength of this product was as follows.

Tensile strength: 10 kg/am" Tensile modulus: 290 kg/am" Breaking elongation: 40% The obtained AM film was fixed to a length of 1 foot, and
The film was reheated at 1"C for 30 seconds. The heat shrinkage rate of the resulting reheated film was measured and the results are shown below.

Hold at 200℃ for 30 minutes 0.05% 250℃
, held for 30 minutes 0.08% The results are shown in Table 1.

(Example 4) The heat treated film obtained in Example 3 above was reheated at 280° C. for 60 seconds in a relaxed state.

The heat shrinkage rate of the obtained reheat-treated film was measured.

The results are shown below.

200℃, 30 minutes 0.11%250
℃, 30 minutes 0.16% Results are shown in Table 1 (Comparative Example 2) The heat shrinkage rate measured for the heat treated film obtained in Example 3, that is, the film before reheat treatment, is as follows. there were.

Hold at 200℃ for 30 minutes 0.65% 250℃
, held for 30 minutes 0.88% The results are shown in Table 1.

(Example 5) The polyetherketone copolymer obtained in Example 1 was
With a twin screw extruder (manufactured by Tamami Tekko Co., Ltd.: PCM-30),
After extrusion molding at 390T, it was made into a pellet.

Using this pellet, a film with a diameter of 25 cm was formed using a T-die.

Next, this film was stretched using a biaxial stretching machine (newly manufactured by Toyo Seiki Co., Ltd.) at a stretching speed of 1000%/min and a stretching temperature of 188%.
Biaxial stretching was carried out at 3°C and at a stretching ratio of 3x3.

Then, the obtained stretched film was fixed to a metal frame and heat treated at 260''C for 30 seconds under foot length.

Next, the heat-treated stretched film obtained above was fixed to a metal frame, and reheat-treated at 200''C for 30 seconds under the foot length.

Regarding the stretched film obtained after reheat treatment.

The heat shrinkage rate was measured. Thermal shrinkage was measured when the stretched film was maintained in a relaxed state at 200°C for 30 minutes and at 250''C for 30 minutes.

The results were as follows.

Hold at 200℃ for 30 minutes 0.15% 250℃
, held for 30 minutes 0.12% The results are shown in Table 2.

(Example 6) The reheat treatment conditions were 250°C with the stretched film in a relaxed state.
The same procedure as in Example 6 was carried out except that the time was changed to 180 seconds. The heat shrinkage rate of the obtained reheat-treated stretched film was as follows.

Hold at 200℃ for 30 minutes 0.18% 250℃
, held for 30 minutes 0.25% The results are shown in Table 2.

(Example 7) The reheat treatment conditions were such that the stretched film was reduced to 3 (l[1°C
The same procedure as in Example 6 was performed except that the heating time was 30 seconds.

The heat shrinkage rate of the obtained reheat-treated stretched film was as follows.

Hold at 200℃ for 30 minutes 0.01% 250℃
, held for 30 minutes 0.02% (Comparative Example 3) In Example 5, the heat shrinkage rate of the heat-treated stretched film, that is, the heat-treated stretched film before reheat treatment, was as follows.

Hold at 200℃ for 30 minutes 0.90% 250℃
, held for 30 minutes 1.15% The results are shown in Table 2.

(Example 8) The polyetherketone copolymer obtained in Example 3 was made into a biaxially stretched film with a stretching ratio of 3 times x 3 times in the same manner as in Example 5, and heat treated under the same conditions. did.

Then, the heat-treated stretched film was fixed to a metal frame and reheated at 300° C. for 30 seconds under the length of the foot. The heat shrinkage rate measured for the stretched film obtained after this reheat treatment was as follows.

Hold at 200℃ for 30 minutes 0.00% 250℃
, held for 30 minutes 0.01% (Example 9) The reheat treatment conditions were 280°C with the stretched film in a relaxed state.
, 60 seconds, but the same procedure as in Example 8 was carried out. The heat shrinkage rate of the obtained reheat-treated stretched film was as follows.

Hold at 200°C for 130 minutes 0.01%250
℃, held for 30 minutes 0.02% The results are shown in Table 2.

(Comparative Example 4) The heat shrinkage rate of the stretched film heat-treated in Example 8, that is, the heat-treated stretched film before reheat treatment, was as follows.

Hold at 200℃ for 30 minutes 0o85%25(1
℃, held for 30 minutes 1.02% The results are shown in Table 2.

[Effect of the invention] In the present invention, the polyetherketone copolymer film is heat treated and reheated, so the polyetherketone copolymer film of the present invention has high heat resistance and resistance at high temperatures. Excellent dimensional stability.

Claims (2)

[Claims] (1) The following formula (I); ▲There are mathematical formulas, chemical formulas, tables, etc.▼The repeating unit represented by (I) and the following formula (II); ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) The composition ratio of the repeating units represented by the formula (I) [molar ratio, (I)/{(
I)+(II)}] is 0.15 to 0.40, and the melt viscosity (zero shear viscosity) at 400°C is 3,000 to 100,000 poise. The film is heat-treated at a temperature between the crystallization temperature and the crystal melting point of the polyetherketone copolymer, and the heat-treated film is heated at a temperature between the glass transition temperature and the crystal melting point of the polyetherketone copolymer. A polyetherketone copolymer film obtained by reheating at a temperature between (2) The polyetherketone copolymer film according to claim 1 is stretched at a stretching ratio of 1.5 to 1.5 in a uniaxial direction or biaxial direction.
Stretched 10 times, the stretched film is heat-treated at a temperature between the crystallization temperature and the crystal melting point of the polyetherketone copolymer, and the heat-treated stretched film is made into a glass of the polyetherketone copolymer. A polyetherketone copolymer film obtained by reheating at a temperature between the transition temperature and the crystal melting point.