JPH03263464A - Polyarylene sulfide resin composition and production thereof - Google Patents

Abstract

PURPOSE:To obtain a polyarylene sulfide resin composition having excellent compatibility, heat-resistance, chemical resistance, etc., by compounding a polytetrafluoroethylene, etc., with one or more solubilizing agents selected from tetrafluoroethylene-olefin copolymer, etc. CONSTITUTION:The objective composition can be produced by melting and kneading (A) 5-30 pts.vol. of polytetrafluoroethylene and/or a copolymer containing tetrafluoroethylene and a fluorovinyl monomer and (B) 95-70 pts.vol. of one or more components selected from tetrafluoroethylene olefin copolymer (e.g. ethylene-tetrafluoroethylene copolymer), polyvinylidene fluoride and vinylidene fluoride copolymer at a temperature above the melting points of the components A and B and melting and kneading 5-30 pts.vol. of the above mixture with (C) 95-70 pts.vol. of a polyarylene sulfide resin at a temperature above the melting points of the components B and C and below the melting point of the component A.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a polyarylene sulfide resin composition containing a polyarylene sulfide resin and a fluororesin, and a method for producing the same, particularly a polyarylene sulfide resin composition containing a polyarylene sulfide resin and a fluororesin. Poly-f, which is well compatible with fluororesins and has excellent heat resistance, chemical resistance, low friction, and abrasion resistance, etc.
The present invention relates to an IJ-rensulfide resin composition and a method for producing the same.

[Conventional technology]

Polyarylene sulfide resins such as polyphenylene sulfide resins have excellent mechanical properties and heat resistance, but when used in sliding parts materials such as gears, bearings, sealing materials, etc., they have low friction. Although it has good wear resistance, it does not have sufficient wear resistance.

On the other hand, fluororesins such as polytetrafluoroethylene and tetrafluoroethylene-bar fluoroalkyl vinyl ether copolymers are known to have chemical resistance, non-adhesiveness, and heat resistance, but they do not have low friction properties. There is a problem that the wear resistance of the material is not sufficient.

Sliding properties can be improved by mixing such a polyarylene sulfide resin with a polydetrafluoro (I) ethylene, or (i) ethylene-berfluoro (T-1, fluoro, or fluorine) copolymer. There have been various proposals to do this.

JP-A-52-129761 discloses a sliding member made of a polyphenylene sulfide resin with graphite, polytetrafluoroethylene, and lubricating oil added thereto.

JP-A-55-45704 discloses a composition containing a polyphenylene sulfide resin, a low crystallinity thermoplastic resin composition, carbon fiber, graphite, and a fluororesin.

JP-A-60-228558 discloses a composition containing a polyphenylene sulfide resin, polytetrafluoroethylene, molybdenum disulfide, an inorganic filler, and a fibrous reinforcing material.

Furthermore, JP-A No. 61-266451 discloses (a) at least one resin consisting of a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin, a tetrafluoroethylene-perfluoropropylene copolymer resin, and a fluoroethyl-lene brobylene ether resin; and a polyphenylene sulfide resin.

[Problem to be solved by the invention]

However, in the production of each of the above-mentioned compositions, polytetrafluoroethylene or tetrafluoroethylene-
Fluororesin such as perfluoroalkyl vinyl ether copolymer is blended with polyphenylene sulfide resin in powder form and kneaded at a temperature above its melting point. The problem is that the fluoroalkyl vinyl ether copolymer powder aggregates to form a macroscopic self-layer, resulting in poor compatibility.

On the other hand, there is a method of mixing polyphenylene sulfide resin and fluororesin powder such as polytetrafluoroethylene and molding the mixture using a ram extruder, etc., or compression molding. is not necessarily uniformly dispersed.

As mentioned above, a composition containing a polyaryl rental resin such as a conventional polyphenylene/insulfide resin and a polytetrafluoroethylene or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer has an affinity for both. Therefore, there was no material with good compatibility that could be uniformly dispersed.

Therefore, the object of the present invention is to finely disperse polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, etc. in a polyaryl rental oxide resin, to have good compatibility, heat resistance, chemical resistance, An object of the present invention is to provide a polyaryl No. 92 ruphide resin composition having excellent low friction properties and wear resistance.

[Means to solve the problem]

As a result of intensive research in view of the above objectives, the present inventors have found that in a resin composition containing a polyarylene sulfide resin and a fluororesin such as polytetrafluoroethylene or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, Polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, etc., and one or two types selected from tetrafluoroethylene-olefin copolymer, polyvinylidene fluoride, vinylidene fluoride copolymer as a compatibilizer. The above is blended and melt-kneaded in advance, and polyarylene sulfide resin is added to the resulting mixture at a predetermined temperature.
It was discovered that a composition that solved the above problems could be obtained by melt-kneading, and the present invention was conceived.

That is, the polyarylene sulfide resin composition of the present invention comprises (a) polytetrafluoroethylene and/or a copolymer containing tetrafluoroethylene and a fluorovinyl monomer, and (b) a tetrafluoroethylene-olefin copolymer.

Contains one or more selected from polyvinylidene fluoride and vinylidene fluoride copolymers and (c) polyarylene sulfide resin, and the volume ratio of the above (a) and the above (b) is 5/95. ~70/30, and said ((a)
+ (b)) and the volume ratio of the above (c) is 5/95 ~
It is characterized by being 30/70.

Further, the method for producing the polyarylene sulfide resin composition of the present invention includes (a) 5 to 30 parts by volume of a copolymer containing polytetrafluoroethylene and/or tetrafluoroethylene and a fluorovinyl monomer; Melt 95 to 70 parts by volume of one or more selected from ethylene-olefin copolymer, polyvinylidene fluoride, and vinylidene fluoride copolymer at a temperature equal to or higher than the melting point of (a) and (b). 5 to 30 parts by volume of the resulting kneaded product and 95 to 70 parts by volume of (c) polyarylene sulfide resin are kneaded at a temperature equal to or higher than the melting point of (6) and (c) above, and the melting point of (a) above. It is characterized in that it is melt-kneaded at a temperature below.

The present invention will be explained in detail below.

In the present invention, the polytetrafluoroethylene (a) is a polymer obtained by polymerizing tetrafluoroethylene (cF2 = CF2), and is expressed by the general formula %. The above-mentioned polytetrafluoroethylene usually has a melt viscosity of 1011-10'' (380°C) and a melting point of 327°C. However, as a commercially available powder product, for example, "Luburon L-5J" manufactured by Daikin Industries, Ltd.
(product name), manufactured by the same company [Polyflon TFBJ (product name), manufactured by Mitsui DuPont Fluorochemical ■ "Teflon TB
914JJ (product name) and the like.

Further, in the present invention, the fluorovinyl monomer to be copolymerized with tetrafluoroethylene is one in which the hydrogen atom of a vinyl group is substituted with fluorine, and has a fluorinated substituent. Examples of the fluorovinyl monomer include perfluoroalkyl vinyl ether.

Examples of copolymers containing the above-mentioned tetrafluoroethylene and fluorovinyl monomers include tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers (
In addition to binary copolymers such as PFA), terpolymer copolymers of tetrafluoroethylene, perfluoroalkyl vinyl ether, and hexafluoropropylene (EPE), and the like can be mentioned.

Note that tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) is generally represented by the following formula: % (wherein, R7 represents a perfluoro substituent such as CF3, CzFs, C3F, etc.) It is something.

The above tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer is usually 104 to 105 poise (
It has a melt viscosity of 380°C) and a melting point of 302-31
It is 0°C.

Commercially available copolymers of tetrafluoroethylene and fluorovinyl monomers include, for example, "Teflon PFAJ (trade name)" manufactured by Mitsui DuPont Fluorochemical Co., Ltd., "Neoflon PFAJ (trade name)" manufactured by Daikin Industries, Ltd.
etc.

- -10 = 14 In the present invention, 0])'s 5 toranol I'l
-Tu Wolene-J-Refin copolymer is composed of detrafluoropoethylene, ethylene, pyrene, butene-1
It is a copolymer with olefins such as A typical example thereof is J-f lene-tetrafluoroethylene copolymer (ETFE). This ethylene-tetrafluoroethylene copolymer is a ethylene-tetrafluoroethylene copolymer (E
TF'E) is usually 104-105 boiz (300-3
It has a melt viscosity of 30°C) and a melting point of 260°C.

As a commercially available product of the above-mentioned ethylene-tetrafluoroethylene copolymer, for example, Daikin Industries ■ [Nephron BT
Examples include FE EP520J (product name).

In the present invention: 1. (b) polyvinylidene fluoride (
P V D F ) is vinylidene fluoride (c112=
It is a polymer obtained by polymerizing CF2), and general 2:
Polyvinylidene fluoride having the following molecular structure usually has a melt viscosity of 2 x 103 to 2 x 10' (210 to 270°C) and a melting point of 160 to 180°C. Such polyvinylidene fluoride is used for injection molding,
Although various grades for extrusion molding and the like are manufactured, there is no particular limitation in the present invention.

Commercially available products of the polyvinylidene fluoride include rKP Polymarco (trade name) manufactured by Kureha Chemical Industries, Ltd. and Neoflon PVDFJ (trade name) manufactured by Daikin Industries, Ltd.

Furthermore, the vinylidene fluoride copolymer is a copolymer in which the main monomers are the above-mentioned vinylidene fluoride and perfluoromonomers such as tetrafluoroethylene and hexafluoropropylene. The copolymer is not limited to a block or random copolymer, but may also be a graft copolymer, and can be produced by radiation irradiation or peroxide catalyst.

The polyarylene sulfide resin (c) used in the present invention is general 2:'□□-(Ar-3-)-(However, A'r
is an aromatic residue and S is sulfur. ) has a repeating unit represented by Here, as the aromatic residue <-Ar-) in the above general 2, for example, (wherein, ), etc.

Among the above Boria' IJ-ren sulfide resins, a typical one is polyphenylene sulfide resin (PPS) represented by general 2:
can be mentioned. Furthermore, a copolymer of about 10 mol % or less of other mercury with the above-mentioned polyphenylene sulfide resin can also be used.

Further, although the above-mentioned resin is uncrosslinked between molecules, it is also possible to use a resin that has been partially crosslinked by a method such as heat treatment.

Such polyphenylene sulfide resin has 30
The melt viscosity at 0° C. is 20 to 30,000 poise, preferably 100 to 15,000 poise.

Moreover, its melting point is usually 280 to 290°C.

As such polyphenylene sulfide resin,
Although various grades of materials for injection molding, extrusion molding, etc. are manufactured, there is no particular restriction in the present invention.

As a commercially available product of the polyphenylene sulfide resin mentioned above, for example, ■Tobren's (Topsin PP5J)
Product name), rAsAIII PPS manufactured by Asahi Glass, 1
(product name), Shin-Etsu Chemical @ [Shin-Etsu PP5J (product name), Hodogaya Chemical ■ "The Steel" 4 3 (product name), etc.

The mixing ratio of the above-mentioned components (a), (b) and (c) is as follows: component (a)/component Q)) in a volume ratio of 5/95.
~70/30, preferably 1.5/85~50/50
It is. If the ratio of component (a)/component (b) is less than 5/95,
(a) The effect of containing the component is insufficient, while 70/
If it exceeds 30, component (a) tends to aggregate alone in the polyarylene sulfide resin, making it impossible to obtain a composition with good compatibility between the polyarylene sulfide resin and the fluororesin.

In addition, the blending ratio of (c) polyarylene sulfide resin is 5/95 to 30/70, preferably 15/85 to 3 in volume ratio of ((a) component 〇 component)/(c) component.
It is 0/70.

If the above volume ratio is less than 5/95, component (a) and (b)
The component shows a tendency to agglomerate upon kneading with component (c);
) No longer stably and uniformly dispersed in the ingredients. On the other hand, 30/
If it exceeds 70, the effects of improving heat resistance, chemical resistance, low friction properties, wear resistance, etc. due to the inclusion of fluororesin will be insufficient.

In the present invention, the blending ratio of various constituent components is expressed as a volume ratio, and the volume ratio is obtained by dividing the weight of each component by its density.

In addition to the above-mentioned components, the composition of the present invention may contain silicone oil, molybdenum disulfide, a mold release agent, a lubricant, a heat stabilizer, a foaming agent, an inorganic filler, and the like, if necessary.

Next, a method for producing the polyarylene sulfide resin composition of the present invention will be explained.

In the present invention, components (a) and (b) are first kneaded (first kneading step). The first kneading step is (a)
It is carried out at a temperature that is higher than the melting point of the component and component (b) and lower than the thermal decomposition initiation temperature. Specifically, 310 to 340°C is preferable,
Particularly preferred is 320 to 340°C. The time required for kneading varies depending on the resin mixing ratio and the kneading equipment used, but for example, when using a Weisenberg extruder, the time required for kneading is 1 to 30 minutes.
minutes is preferred, particularly 5 to 15 minutes.

Next, the kneaded product thus obtained is kneaded with the polyarylene sulfide resin composition and various additives added as necessary (kneading step of 5-1 and 16-2). The second kneading step is carried out at a temperature below the melting point of component (a) and above the melting points of components (b) and (c). Specifically, when polyphenylene sulfide resin is used as the polyarylene sulfide resin, 280
-300 degreeC is preferable, and 285-290 degreeC is especially preferable. Further, the time required for cross-talk is preferably 1 to 30 minutes, particularly preferably 5 to 15 minutes, when the Weisenberg extruder is used.

Note that the methods for the above-mentioned first and second kneading are not particularly limited, but since component (a) has a high viscosity even in a molten state during the first melt-kneading, for example, a Weissenberg extruder or screw kneading method is used. It is preferable to use a die extruder or the like. Further, prior to melting and mixing, it is preferable to pre-mix the various components in the form of powder or pellets, as in the case of mixing ordinary thermoplastic resins.

A schematic diagram of the polyarylene sulfide resin composition of the present invention obtained in this manner is shown in FIG. In FIG. 1, component (a) 2 is dispersed in a matrix j of polyarylene sulfide resin while being included in component (b). Note that the entire area of component (a) does not need to be covered by component (b) (4'' in the figure), and may be partially exposed (4 in the figure). No. 3 is a particle containing component (b) alone.

The particle size of component (a) included in component (b) is usually 5 to 50 p, preferably 5 to 15 p. Also (b
) The particle size of the component alone is usually 5 drops.

In FIG. 1, only particles with remarkable characteristics are numbered.

[For production]

The polyarylene sulfide resin composition of the present invention is (
Since it contains component (a) and (c) component (b) as a compatibilizer for component a, component (a) is uniformly dispersed in the matrix of component (c), resulting in a dark brown or blackish brown color with good compatibility. It exhibits an appearance unique to polyarylene sulfide resin.

When such a resin composition is observed with an electron microscope, it is found that particulate matter (island structure) in which the component (b) of the compatibilizing agent surrounds the fine particles of the component (a) (c) Polyaryl 7-8 Ren@J is uniformly dispersed in the phase (sea structure) of the ruphide resin composition.

The reason why such an effect is obtained is that in the manufacturing method, components (11,) and ()]) are melt-kneaded, and component (a) is dispersed in component CI)). This kneaded product is further melt-kneaded with component (c) at a predetermined temperature, resulting in a reduction in which component (a) is present in component (c) while being included in component (0)), and (c) This is believed to be because component (a) is well compatible with component (b), which has an affinity with the component.

In addition, ar, which is obtained by kneading each component of the composition ratio of the present invention at the same time,
When you observe things, you can feel the power of white separation.

When this white separated substance was analyzed using a scanning X-ray microphone and a 7-alienizer, it was found to be fluorine-based resins of components (a) and (b). This is thought to be because the component (a) is not compatibilized with the polyarylene sulfide resin and therefore aggregates, making it impossible to obtain a uniform composition.

Furthermore, in the case C as in the present invention, which has a first kneading step I--degree l· and a second kneading step, the temperature of the second kneading process is (a
) If the temperature is 1-7% above the melting point of the component, white separation is likewise tolerated. This is because if the temperature during the kneading step in step 1' is higher than the melting point of component (a), component (a,) (
b) The state of bonding and dispersion in the components remains 2, (
c) It becomes difficult to disperse uniformly in the ingredients, and (a
This is thought to be due to component () and component (b) agglomerating and leaving C.

〔Example〕

The invention is explained in more detail in the following examples.

Note that the raw resins used in each Example and Comparative Example are as follows. .

(a) Component polytetrafluoro-11 ethylene PTFE: [manufactured by Daikin Industries [Lube Tl1l]
-5-1, melting point 327℃Cotetralu fluoroethylene-perfluoroalkyl vinyl ether copolymer PFA: [:Mitsui DuPont FLO1 Cochemical ■[DEF DON PFA 340J, melting point 3 [)2~3xo'ta9 20 11] ) component ethylene-detrafluoro-ethylene copolymer ETFE:
[:Daikin R Industry @1 Neo 711 :/ BTfl
B mouth P520, melting point 26o'ta polyfluorinated vinyl! Reden pvI) F: c rsolef manufactured by Belgian Sorbet
#1010J, melting point 177°C] (c) Ingredient Borifueni heat non-sulfide resin PPS: [■ Manufactured by Toblen [Toblen T-4-h melting point 280°C] Examples 1 to 7 and Comparative Examples 1 to 3 1st Component (a) polytetrablue i, -o ethylene or tetrafluoroethylene-verflume[]] alkylvinylcochyl copolymer &, (b
) component ethylene-dedone-fulmero-J dylene copolymer or polyvinylidene fluoride, and the Weissenberg extruder 2.
The pellets were melted and kneaded at 5.70 rpm, and then the pellets were mixed with the component (c) polyphenylene sulfide resin. Melt-kneaded in the proportions shown in Table 1, and further fed to a Weisenberg extruder,
Pellets of the polyphenylene sulfide resin composition were obtained by melt-kneading at a rotational speed of 70 rpm.

The pellets of the polyph s5 nylene sulfide resin composition thus obtained were pressed to a size of 70 mmφ
．． The appearance was observed as a 3 mm disk. In addition, a sample of this polysulfide resin composition prepared by the freeze-fracture method was observed using a scanning electron microscope. Based on the observation results described in Section 2, the compatibility was evaluated according to the following criteria. Dispersed in,.

△: Slight white linear objects of fluororesin are observed in the appearance.

×: A white separated substance of fluororesin was observed in the appearance.

The results are shown in Table 1 along with the kneading temperature. 1 2 Also, for comparison, component (a), component (b), and component (c)
A composition in which the blending ratio of the components is outside the scope of the present invention (Comparative Example 1.2) and a composition in which each component is mixed in one step (Comparative Example 3) are pelletized in the same manner and treated in the same manner. Compatibility was evaluated. The results are also shown in Table 1.

23- As is clear from Table 1, the polyarylene sulfide resin composition of the present invention has a uniform brown or blackish brown appearance, and the fluororesin and the polyphenylene sulfide resin composition are well compatible. There is.

On the other hand, in the compositions of Comparative Examples 1 to 3, white linear objects or white separated substances were observed in the appearance.

〔Effect of the invention〕

As detailed above, the polyarylene sulfide resin composition of the present invention comprises (a) polytetrafluoroethylene and/or a copolymer containing tetrafluoroethylene and fluorovinyl monomer, and (b) tetrafluoroethylene- Olefin copolymer, polyvinylidene fluoride,
After melt-kneading one or more selected vinylidene fluoride copolymers at a temperature equal to or higher than the melting point of (a) and (b), the resulting kneaded product and (c) polyarylene sulfide resin Since the components are melt-kneaded at a temperature higher than the melting point of (c) and lower than the melting point of (a), the components (a) and (c) have good compatibility.

Such a polyarylene sulfide resin composition of the present invention has excellent heat resistance, chemical resistance, low friction property, wear resistance, etc., and is suitable for sliding members such as gears, bearings, and sealing materials.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the compatibilized state of the polyarylene sulfide resin composition of the present invention. 1... Polyarylene sulfide resin matrix 2... (a) component 3... (b) component 4.4'... Ratio of (a) component included in (b) component Applicant Person Tonen Petrochemical Shunji Onishi Co., Ltd.

Claims (3)

[Claims] (1) (a) polytetrafluoroethylene and/or a copolymer containing tetrafluoroethylene and a fluorovinyl monomer; (b) a tetrafluoroethylene-olefin copolymer;
Contains one or more selected from polyvinylidene fluoride and vinylidene fluoride copolymers, and (c) polyarylene sulfide resin, and the volume ratio of the above (a) and the above (b) is 5/95. ~70/3
0, and the volume ratio of the above ((a)+(b)) to the above (c) is from 5/95 to 30/70. (2) The polyarylene sulfide resin composition according to claim 1, wherein the tetrafluoroethylene-olefin copolymer is an ethylene-tetrafluoroethylene copolymer. (3) (a) 5 to 30 parts by volume of polytetrafluoroethylene and/or a copolymer containing tetrafluoroethylene and a fluorovinyl monomer; and (b) a tetrafluoroethylene-olefin copolymer, polyvinylidene fluoride, 95 to 70 parts by volume of one or more selected from vinylidene chloride copolymers, as described in (a) and (b) above.
5 to 30 parts by volume of the resulting kneaded product and 95 to 70 parts by volume of (c) polyarylene sulfide resin are melt-kneaded at a temperature equal to or higher than the melting point of (b) and (c).
A method for producing a polyarylene sulfide resin composition, which comprises melting and kneading at a temperature higher than the melting point of (a) and lower than the melting point of (a).