JP2003048982A - Polyphenylene sulfide resin, polyphenylene sulfide film and method for producing them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyphenylene sulfide(PPS) resin raw material having less volatile component in processes such as a heating, vacuum, pressurizing and molding process, etc., and a PPS resin film. SOLUTION: This polyphenylene sulfide resin has <=0.1 wt.% volatile component on heating it at 250 deg.C. The method for producing the resin is provided by supplying the polyphenylene sulfide resin and an entrainer to an extruder, removing the entrainer and then melting and extruding the polyphenylene sulfide resin, and more concretely, supplying the polyphenylene sulfide resin and the entrainer such as water, N-methylpyrrolidone, ethylene glycol, triethylene glycol, etc., to the extruder, removing the entrainer and then melting and extruding the polyphenylene sulfide resin. The polyphenylene sulfide film is obtained by deaerating the obtained resin under vacuum and then melting and film- forming.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a polyphenylene sulfide (PPS) resin in which volatile components generated in a process such as melt extrusion, vacuum drying and heating of polyphenylene sulfide (PPS) resin are reduced as much as possible, and a method for producing the same. It is a thing.

[0002]

2. Description of the Related Art Polyphenylene sulfide (PPS) resins are often complicated in polymerization process, easily generate low molecular weight oligomer components, and easily decompose to generate decomposed gas when heated. Are known.
For this reason, immediately after the polymerization, after washing with N-methylpyrrolidone (NMP), which is a solvent at the time of polymerization, washing with warm water and drying with hot air have been performed to remove foreign matters.

[0003]

However, such NMP / warm water washing cannot sufficiently remove impurities, and therefore the PPS raw material thereof is subjected to vacuum drying, heat drying, heat treatment, melting, etc. Not only these impurities are scattered in the process and contaminate each process, but the obtained PPS sheet also contains a gelled product, a coloring matter, and a foreign matter, and only a poor quality sheet can be obtained.

[0004]

[Means for Solving the Problems] The inventors of the present invention have made extensive studies in view of the above-mentioned problems, and as a result, have found the polyphenylene sulfide resin of the present invention.

That is, the polyphenylene sulfide (PPS) resin of the present invention has a volatile component of 0.1% by weight or less when heated to 250 ° C. And, more preferably, it is a PPS resin having a content of 0.02% by weight or less.

Further, the method for producing a polyphenylene sulfide film of the present invention is characterized by forming a film by using such a resin according to the present invention.

More specifically, polyphenylene sulfide (PPS) resin, water, N-methylpyrrolidone (NM)
P), ethylene glycol (EG), triethylene glycol (TEG), and other entrainers are supplied to the extruder, the entrainers are first removed in vacuum, and then the molten polyphenylene sulfide (PPS) resin is used as residual oxygen content of 0. It is a polyphenylene sulfide (PPS) resin obtained by melt-extruding to 1% or less.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below.

The polyphenylene sulfide (PPS) resin referred to in the present invention is a resin containing 70 mol% or more of poly-para (P) -phenylene sulfide, and a composition of less than that has heat resistance, dimensional stability and mechanical properties. This is because only those with inferior characteristics such as Of course, a small amount of poly-meta (m) -phenylene sulfide polymer or other monomer having an aryl group, a biphenyl group, a terphenyl group, a vinylene group, a carbonate group, etc., for example, in an amount of less than 30 mol% in any form It may be copolymerized and mixed.

The molecule of the PPS resin is preferably a linear or linear polymer having a molecular weight of 50,000 or more, but it is not always necessary to be particular about this, and even a polymer having a branched chain has a partially crosslinked structure. May be included. As a method for producing a PPS resin, US Pat. No. 3,354,129 may be referred to. The PPS resin may be used alone or as a polymer alloy. As the alloy polymer, use polyester, liquid crystal polyester, polyamide, polyolefin, polyimide, polyamideimide, polyetherimide, polyarylate, polyetherimide, modified polyphenylene sulfide, polyetheretherketone, polyethersulfone, polysulfone, etc. However, the present invention is not limited to these. The mixing ratio with the resin is preferably about 0.1 to 30% by weight.

Since a large amount of the low molecular weight oligomer contained in the PPS resin immediately after being polymerized in this way remains, considerable components can be removed by washing with a solvent such as diphenyl ether, NMP and warm water, but boiling After 36 hours of extraction with xylene, the amount of oligomer is 1.5.
The volatile component contained about 1% by weight or more when it was heated to about 250% by weight and contained a large amount of impurities.

Then, the PPS resin is heated, pressurized, vacuumed,
When molded and used for various purposes, impurities do not scatter in each process and contaminate each process, and the obtained PPS sheet does not contain gelled substances, colored substances, foreign substances, etc. In order to obtain a high quality PPS sheet, a purified polyphenylene sulfide (PPS) resin having a volatile component of 0.1% by weight or less, preferably 0.02% by weight or less when heated to 250 ° C. is used. It is necessary to use. It is preferable that such impurities are not contained, that is, 0% by weight,
In the actual refining process, the above range is a practical range considering the harmful effects of impurities and the deterioration of productivity due to the strengthening of refining.

P containing almost no such impurities
In order to obtain PS resin, first, PPS resin powder is mixed with water and N-
Methylpyrrolidone (NMP), ethylene glycol (E
G), triethylene glycol (TEG) and other typical solvents for dissolving PPS low molecular weight oligomers, or a mixed solvent of two or more selected from ordinary solvents. Then, the raw material is not dried or is not dried as it is, and the entrainer which is the solvent of the PPS low molecular weight oligomer and the PPS resin powder are fed to an extruder such as a twin-screw vent simultaneously or separately.
After partially or completely melting the PS resin, the entrainer is first removed from the vent port, and then the polyphenylene sulfide (PPS) resin is completely melted and then melt extruded.

Of course, a single-stage vent extrusion may be used,
A tandem / vent extruder in which two or more extruders are connected in series is preferable because it has a higher removal effect. It is practical that the mixing ratio of the entrainer and the PPS resin is in the range of about 5 to 100 parts by weight, preferably 7 to 50% by weight, based on 100 parts by weight of the PPS resin. As the amount of entrainer increases, the extraction rate / amount of impurities will increase / increased, but the extrusion productivity will be inferior.Therefore, the raw material immediately after polymerization should be washed with the above-mentioned solvent such as water or EG. In some cases, it may be more efficient to use raw materials without drying them. In the case of water, if a raw material containing water having a water content of about 20 to 50% by weight is used, it is possible in many cases to further remove impurities efficiently. The place where the entrainer is injected and mixed into the extruder may be supplied as a mixed raw material of the PPS resin and the entrainer at the hopper portion for supplying the PPS raw material, or after the PPS resin is fed from the extruder hopper. The PPS resin may be supplied at any position in the extruder cylinder in a portion where the PPS resin is not yet melted or completely melted. However, when water is used for the entrainer, the boiling point is 100.
Since the temperature is as low as ℃, when the water is supplied, it may evaporate and flow back to the supply side of the cylinder. In such a case, remove the evaporated water at any position up to the bottom of the popper. A vent port may be provided and removed.
Practically, ethylene glycol (EG) with a high boiling point
Alternatively, it is preferable to use triethylene glycol (TEG) because there is no backflow and the triethylene glycol (TEG) can be removed from the vent port at the tip of the supply section.

As described above, the PPS resin and the entrainer are mixed with each other, and the PPS resin is heated from 280 ° C. to 320 ° C. to be completely melted, and a forced vacuum is drawn from a vent port where pressure is prevented from rising. Remove the entrainer from. Of course, in the entrainer, PPS oligomer, reactant, volatile component, NMP of solvent
Etc., it is necessary to provide a vacuum trap. Since the entrainer is removed in the molten state of the PPS resin as described above, the impurities of PPS can be removed more efficiently than the extraction at a low temperature of about room temperature to 100 ° C. The degree of vacuum is 5 torr or less, preferably 1
It is preferable that the pressure is not more than torr, more preferably not more than 0.5 torr.

It is important that the atmosphere in contact with the molten PPS during the melt extrusion is such that the residual oxygen content is 0.1 vol% or less, preferably 0.01 vol% or less. For this purpose, it is necessary to make the hopper part overflow with nitrogen gas or to use a vacuum hopper. This is because when oxygen is present during melting, the PPS resin undergoes a cross-linking reaction or an oxidation reaction to make the resin infusible or colored, and also generates a gas that corrodes metals such as hydrogen disulfide and sulfur dioxide. This is because it is not preferable.

The method for producing the PPS resin according to the present invention will be specifically described below.

As the PPS resin itself, one produced by a conventionally known method can be used. For example, sodium sulfide and p-dichlorobenzene can be replaced with N-methyl-2.
-Reacting at high temperature and pressure in an amide-based polar solvent such as pyrrolidone (NMP). If necessary, a copolymerization component such as trihalobenzene can be included. Caustic potash, carboxylic acid alkali metal salt and the like are added as a polymerization degree adjustor and a polymerization reaction is carried out at 230 to 280 ° C. After the polymerization, the polymer is cooled, and the polymer is made into an aqueous slurry and filtered with a filter to obtain a granular polymer. This is stirred in an aqueous solution of acetate or the like at 30 to 100 ° C. for 10 to 60 minutes,
It is washed with ion-exchanged water at 30 to 80 ° C several times and dried to obtain a PPS powder having a water content of 35%. The powdered polymer is NM at an oxygen partial pressure of 10 Torr or less, preferably 5 Torr or less.
After washing with P, it is washed several times with ion-exchanged water at 30 to 80 ° C., and dried under reduced pressure of 5 Torr or less. The polymer thus obtained is a substantially linear PPS polymer, and the melt crystallization temperature Tmc of the PPS resin is 160-160.
It is in the range of 190 ° C. The resin may contain, if necessary, other polymer compounds or inorganic or organic compounds such as silicon oxide, magnesium oxide, calcium carbonate, titanium oxide, aluminum oxide, crosslinked polyester, crosslinked polystyrene, mica, talc, kaolin and the like. Various additives may be added as a polymer compound additive such as a decomposition inhibitor, a heat stabilizer and an antioxidant.

Ethylene glycol 3 as an entrainer was added to 100 parts by weight of the PPS raw material thus obtained.
0 parts by weight are mixed and fed to a hopper of a twin-screw vent extruder in a nitrogen stream in a state where oxygen is substantially absent, and P
After melting the PS resin at 300 ° C., the entrainer EG is removed by reducing the pressure to about 1 Torr from the vent port of the twin-screw vent extruder. At this time, the PPS oligomer and impurities are mixed and removed in the entrainer. Then, the molten PPS resin was extruded into a fibrous form, the gut was cut in water, and the content of impurities of the present invention was such that polyphenylene sulfide (PPS) had a small volatile component of 0.1% by weight or less when heated to 250 ° C. ) Resin can be obtained.

More preferably, the PPS raw material is deaerated and dried in a vacuum state of 1 Torr or less to obtain a raw material having a smaller impurity content, and then the raw material is supplied to an extruder and melted. Subsequently, in order to remove foreign matters in the melt, the molten resin is appropriately extruded while being filtered with a filter, for example, sintered metal, porous ceramics, sand, wire mesh or the like. After that, if necessary, weigh it with a gear pump and then discharge it from the die, and apply it to the cooled drum by electrostatically applying method, air chamber method, air knife method, press roll method etc. which are conventionally known adhesion means. Then, it is brought into close contact with the cooling medium, solidified by cooling, and rapidly cooled to obtain an unoriented amorphous film. Contact the film on a heated roll for 9
The temperature is raised to 0 to 130 ° C., the film is stretched 2.5 to 4 times in the longitudinal direction, and once cooled, the end portion of the film is bitten by a tenter clip and the width direction is set to 100 to 160 ° C.
It is stretched 4 times and then heat-treated at 200 to 280 ° C. for about 10 to 100 seconds to obtain a biaxially oriented PPS film. Of course, the stretching method is not limited, and the simultaneous biaxial stretching method can be used instead of the sequential two-hour stretching method. The driving method of the film gripping clip at this time is a screw method, a pantograph method, a linear motor driving method, etc. The linear motor drive method is preferable because it facilitates stretching control. The manufacturing method of these is as described in JP-B-63-12772.

The heat distortion temperature thus obtained is 90
The biaxially oriented film at about 0 ° C. at a temperature of 250 to 350 ° C. near the melting point of the PPS film in an oxygen atmosphere,
Alternatively, the temperature is raised stepwise, and the temperature range is from 1 minute to 1 minute.
By heat treatment for about 0 hours, the thermal deformation starting temperature becomes 2
A polyphenylene sulfide (PPS) film having a temperature of 00 ° C. or higher is also obtained.

The biaxially oriented PPS film thus obtained has a small tan δ, has a small tan δ dependency at high frequencies, and has excellent electrical characteristics, and is therefore effectively used for high frequency capacitor applications and the like. Further, since both the thermal expansion coefficient α and the humidity expansion coefficient β are small and the soldering resistance is excellent, it can be used for applications requiring heat resistance such as an IC substrate base film.

[0023]

[Measurement Method of Physical Properties] Next, the measurement method used in the present invention will be described below. 1. Thickness unevenness (%): Anritsu film thickness tester KG601A and electronic micrometer K306
Using C, the thickness of a film sampled in a width of 30 mm and a length of 40 m is continuously measured. Maximum thickness TMAX
(Μm) and the minimum thickness TMIN (μm), the fluctuation range R is calculated by R = TMAX-TMIN, and the average thickness TAVE (μ
The thickness unevenness (%) = R / TAVE × 100 was determined from m). 2. Surface roughness (μm): Maximum surface roughness Ry is defined by JIS B
According to 0601, measurement was performed at room temperature with a measurement length of 2 mm and a cutoff of 0.25 mm. As the measuring device, a three-dimensional surface roughness meter manufactured by Kosaka Laboratory Ltd. was used. 3. Mechanical properties: The tensile strength and elongation of the film are JIS
The elastic modulus (Young's modulus) is measured according to the method specified in K7127 and is measured according to JIS Z1702 using an Instron type tensile tester at 25 ° C. and 65%.
It was measured in an RH atmosphere. 4. Amount of volatile components when heated to 250 ° C .: Weighing bottle was washed with a detergent, replaced with methanol and washed, then left in an oven at 100 ° C. for 3 hours, weighed W0, stored in a desiccator, and weighed A PPS raw material of weight W2 is put in a bottle, heated in an oven at 250 ° C. for 1 hour, left to cool to room temperature in a desiccator, and weighed W1 again to measure the heating loss.

Heat loss = (W2 + W0-W1) / (W
2) Calculate with 100. Example 1 Sodium sulfide and p-dichlorobenzene were mixed with N-methyl-
The reaction is carried out in a 2-pyrrolidone (NMP) solvent at high temperature and high pressure. Caustic potash is added as a degree-of-polymerization regulator, and a polymerization reaction is carried out at 280 ° C. After the polymerization, the polymer is cooled, and the polymer is made into an aqueous slurry and filtered with a filter to obtain a granular polymer. This is stirred for 60 minutes in an 80 ° C. aqueous solution of acetate, and washed and dried 5 times at 80 ° C. with ion-exchanged water to obtain PPS powder.

The powdered polymer is washed in NMP at an oxygen partial pressure of 1 torr or less, washed with ion-exchanged water at 80 ° C. five times, and dried under reduced pressure of 1 torr or less. The polymer thus obtained is a substantially linear PPS polymer, 2
The volatile component when heated to 50 ° C. contains a large amount of volatile component of 0.4% by weight, and the melt crystallization temperature Tmc is 16
It was 5 ° C.

Ethylene glycol 3 as an entrainer was added to 100 parts by weight of the PPS raw material thus obtained.
0 parts by weight, 0.05% by weight of calcium carbonate having a particle size of 0.6 μm as an additive, and additives such as a heat stabilizer and an antioxidant are added so that there is substantially no oxygen in the nitrogen stream, and the oxygen partial pressure is After supplying the twin-screw extruder hopper in a state of 1 Torr or less to melt the PPS resin at 300 ° C., the entrainer EG is removed by reducing the pressure to about 1 Torr from the vent port of the extruder. At this time, the PPS oligomer and impurities are mixed and removed in the entrainer. Thereafter, the molten PPS resin was extruded into a fibrous form, the gut was cut in water, and the content of impurities of the present invention was such that polyphenylene sulfide (PPS) had a low volatile content of 0.06% by weight when heated to 250 ° C. Get pellets.

Further, the PPS pellets were degassed and dried under a vacuum condition of 1 Torr or less to further reduce the impurity content to 0.0.
After making the raw material as small as 1% by weight, the raw material is supplied to an extruder and melted. The molten sheet was extruded through a filter box that cuts foreign matter of 10 μm or more into the melt and inclined from a crow mouth type die having a lip width of 1200 mm and a lip gap of 1.5 mm. By applying an electrostatic charge to the molten film thus extruded, the surface temperature is kept at 25 ° C., and saturated steam is sprayed onto the drum,
The film was adhered to a casting drum (1,500 mm in diameter) on which a water droplet film (thickness: about 0.1 μm) was formed, and then cooled and solidified.

The cast film thus obtained had an amount of volatile components of less than 0.001% by weight, contained substantially no volatile components, and was an amorphous, non-oriented film. The film was supplied to a longitudinal stretching machine composed of a heating roll group, stretched 3.6 times at a film temperature of 100 ° C., subsequently stretched 3.5 times at 100 ° C. in the width direction using a tenter, and further 270 ° C. Was heat-treated for 15 seconds to cut the edges at the edges, to obtain a biaxially oriented film having a thickness of 2 μm. There is no film breakage or die streak formation during the 48-hour film forming process, there is no coloring or gelation, there is no defect on the surface or inside, and the thickness variation in the longitudinal direction is 5%. The film was good, and was particularly suitable for use in capacitors. Comparative Example 1 The same as Example 1 except that the PPS powder polymerized in Example 1 (containing 0.4% by weight of volatile components at 250 ° C.) was fed to a single-screw extruder instead of being fed to a twin-screw extruder. The film was formed in exactly the same manner.

Since the entrainer cannot be supplied or removed by the single-screw extruder, the volatile component at 250 ° C. in the obtained pellets is 0.43% by weight.
And contained many volatile components. Even after vacuum drying, the content of volatile components was 0.35% by weight. For this reason, die streaks are severely generated during film formation, and the die must be cleaned at intervals of 4 hours, and the film is frequently broken during stretching, resulting in poor productivity. The obtained quality also had surface and internal defects such as die streaks, coloring, and foreign matter, and the thickness unevenness was as large as 18% in the longitudinal direction. When the film was heated to 250 ° C., it contained 0.18% by weight as a volatile component.

[0030]

EFFECTS OF THE INVENTION By using a PPS raw material having a low volatile component of 0.1% by weight or less when heated to 250 ° C., it can be produced when used as a raw material for film formation, heating, vacuum, pressurization and molding. It is possible to obtain a sheet / film having good properties and good quality. Such a film can be preferably used as an industrial material for electrical insulation and electric circuit board applications. Further, the film thus obtained becomes a sheet having surface smoothness, thickness homogeneity, and defect-free surface inside, and can be preferably used for various applications.

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Claims (7)

[Claims] 1. The volatile component when heated to 250 ° C.
A polyphenylene sulfide resin, which is 1% by weight or less. 2. A method for producing a polyphenylene sulfide resin, which comprises supplying the polyphenylene sulfide resin and an entrainer to an extruder, removing the entrainer, and then melt-extruding the polyphenylene sulfide resin. 3. The entrainer is one or a mixed entrainer selected from a solvent capable of dissolving a low molecular weight polyphenylene sulfide oligomer represented by water, N-methylpyrrolidone, ethylene glycol and triethylene glycol. The method for producing the polyphenylene sulfide resin according to claim 2. 4. A residual oxygen content of 0.
3. Melt extrusion is performed at 1% or less, and the melt extrusion is performed.
Alternatively, the method for producing the polyphenylene sulfide resin according to 3 above. 5. A polyphenylene sulfide sheet produced by using the polyphenylene sulfide resin according to claim 1. 6. The polyphenylene sulfide sheet according to claim 5, wherein the polyphenylene sulfide sheet is a polyphenylene sulfide film. 7. The polyphenylene sulfide film according to claim 6, which is stretched in the longitudinal direction and / or the width direction.