JPH0680875A - Polyarylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition consisting of a polyarylene sulfide resin, a thermoplastic elastomer, a specific compound and molybdenum disulfide and useful as a sliding material having low friction under high-speed sliding and remarkably suppressed in heat release. CONSTITUTION:The objective composition contains 100 pts.wt. resin mixture consisting of (A) 50-99wt.% polyarylene sulfide resin (preferably polyparaphenylene sulfide resin composed of units of formula I), (B) 50-100wt.% thermoplastic elastomer, (C) 0.1-10 pts.wt. compound selected from aromatic maleimide compounds of formula II and formula III [R1 is divalent organic group containing (substituted)phenylene; R2 is divalent hydrocarbon; (n) is 0-2] and (D) molybdenum disulfide of 0.1-35 pts.wt. based on 100 pts.wt. total amount of these components A to C. Furthermore, examples of the compound of formula I include p-phenylene bismaleimide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding material, in particular, a polyarylene sulfide resin composition useful as a sliding part that can be used under high speed sliding.

[0002]

2. Description of the Related Art Polyphenylene sulfide (hereinafter referred to as "P
Polyarylene sulfide resins represented by resins (abbreviated as "PS") are known as high performance engineering plastics having excellent mechanical properties, heat resistance, chemical resistance and electrical insulation. One of its typical uses is sliding parts (friction / wear parts) that are used under high load making the most of their high rigidity.
It is used as a composition comprising PPS and a reinforcing fiber such as glass fiber, carbon fiber or aramid fiber, or a composition comprising PPS and such a reinforcing fiber and a fluororesin typified by polytetrafluoroethylene.

The sliding material composed of the PPS resin composition as described above causes softening or seizure of the material due to frictional heat storage under high speed sliding. Therefore, the sliding material is used under low speed sliding with little frictional heat storage. Limited to use in.

As an attempt to further improve the slidability of sliding parts made of the above PPS resin composition, these PPS are used.
It has been proposed to add a small amount of potassium titanate whiskers, graphite, silica, aluminum silicate, titanium dioxide or a thermosetting resin to the resin composition. However, if the slidability improving effect is not sufficiently achieved or P
There has been a problem that any of the original excellent properties of the PS resin composition is impaired. Moreover, it has not yet been made possible to be used under high speed sliding.

Under the circumstances as described above, it is required that a sliding material made of a PPS resin composition suppresses heat generation, enables use under high-speed sliding, and improves rigidity at high temperature. Has been.

[0006]

DISCLOSURE OF THE INVENTION An object of the present invention is to reduce the friction coefficient under high-speed sliding and its variation, and to reduce the heat generation, which is useful as a sliding material for polyarylene sulfide (hereinafter, referred to as “polyarylene sulfide”). Abbreviated as "PAS").

[0007]

The above-mentioned objects are (A) P
100 parts by weight of a resin mixture comprising 50 to 99% by weight of AS resin and 50 to 1% by weight of (B) thermoplastic elastomer,
(C) 0.1 to 10 parts by weight of at least one compound selected from the aromatic maleimide compounds represented by the following general formulas (1) and (2), and (E) reinforcing fiber 5 as an optional component. ~ 100 parts by weight and / or inorganic filler 5 ~
PAS consisting of 80 parts by weight and (D) molybdenum disulfide as an essential component [0.1 to 35 parts by weight based on 100 parts by weight of the total of the above components (A), (B), (C) and (E). This is achieved by the resin composition.

[0008]

[Chemical 3] In the formula (1), R ₁ is a divalent organic group containing a phenylene group or a phenylene group having a substituent.

[0009]

[Chemical 4] In the formula (2), R ₂ is a divalent hydrocarbon group and n is 0, 1 or 2.

Conventionally, even if a small amount of molybdenum disulfide (MoS ₂ ) was added to a thermoplastic resin, its slidability could not be greatly improved. However, the above-mentioned (A) PAS resin,
By adding molybdenum disulfide to a resin composition composed of (B) a thermoplastic elastomer and (C) an aromatic maleimide compound, sliding can be performed without impairing various properties of the unadded resin composition, particularly compatibility and toughness. It was surprising that the mobility was significantly improved.

The PAS resin used in the present invention is a polymer which is substantially composed of repeating units -RS- (R: arylene group). Preferably, the following formula (3)

[Chemical 5] A polyparaphenylene sulfide resin having a repeating unit represented by, and a random copolymer and a block copolymer containing the repeating unit in an amount of 70 mol% or more, more preferably 90 mol% or more. As the small amount copolymerization component in the copolymer, an arylene sulfide unit represented by the following formula may be mentioned.

[0012]

[Chemical 6]

PAS resins are generally used in Japanese Patent Publication No. 45-3.
Cross-linking and high molecular weight by heating a polymer having a relatively small molecular weight obtained by the production method typified by Japanese Patent No. 368 after polymerization in an oxygen atmosphere after polymerization or by adding a crosslinking agent such as peroxide and heating. So-called heat-crosslinking PAS resin, and Japanese Examined Patent Publication No. 52-12240.
There are linear and high molecular weight polymers obtained by the production methods represented by JP-B-54-8719 and JP-A-61-7332, so-called linear PAS resins, and the like, but in the present invention, Either can be used.

The melt viscosity of the PAS resin used in the present invention is not particularly limited as long as a molded product can be obtained by a usual method such as injection molding or extrusion molding, but the temperature is 300.
From the viewpoint of resin physical properties and moldability, those having an apparent melt viscosity of 100 poise or more and 30,000 poise or less at a temperature of 10 ° C. and a shear rate of 10 ¹ to 10 ⁴ sec ⁻¹ are preferable.

Examples of the thermoplastic elastomer used in the present invention include diene-based elastomers, polyurethane-based elastomers, polyamide-based elastomers, polyester-based elastomers and polyolefin-based elastomers, and those having high reactivity with aromatic maleimide compounds are preferable. .

The diene elastomer includes a polybutadiene elastomer, a vinyl aromatic hydrocarbon represented by a styrene / butadiene / styrene block copolymer and a styrene / isoprene / styrene block copolymer elastomer, and a conjugated diene. Examples thereof include block copolymer type elastomers. The polybutadiene elastomer is obtained by polymerizing 1,3-butadiene using a polymerization catalyst composed of a transition metal component such as titanium, cobalt, nickel and vanadium and an organoaluminum compound component and a polymerization initiator composed of butyl lithium and other alkyl lithium. Is an elastomer obtained by. Examples of the commercially available product include JSR-BR820 manufactured by Nippon Synthetic Rubber Co., Ltd.

The block copolymer elastomer composed of a vinyl aromatic hydrocarbon and a conjugated diene includes (a) a styrene / butadiene / styrene type block copolymer elastomer having a styrene content of 10 to 50% by weight (hereinafter referred to as "S").
(BS-based elastomer)), (b) styrene / ethylene / butylene / styrene / block copolymer (SEB) obtained by selectively hydrogenating these block copolymers.
S elastomer), and (c) these (a), (b)
A modified block copolymer obtained by adding a small amount of unsaturated dicarboxylic acid or its derivative to the block copolymer of is mentioned.

The unsaturated dicarboxylic acid or its derivative contained in the modified block copolymer referred to herein may be a known one, for example, maleic acid, fumaric acid, chloromaleic acid, itaconic acid, cis-4-cyclohexane- 1,2
-Dicarboxylic acids, as well as acid anhydrides, esters, amides, imides and the like of these dicarboxylic acids. Among them, maleic acid, fumaric acid and maleic anhydride are more preferable.

Commercially available products of the SBS elastomer, SEBS elastomer and modified block copolymers thereof can be obtained. For example, as the SBS elastomer, Asahiprene T430 (manufactured by Asahi Kasei),
Tuftec H1041 as SEBS elastomer
(Manufactured by Asahi Kasei), Kraton G1652 (manufactured by Shell Kagaku), SBS-based elastomer acid-modified block copolymer Toughprene 912 (manufactured by Asahi Kasei), SEBS
Tuftec M-1913 (Asahi Kasei Corp.) and Kraton FG as acid-modified block copolymers of elastomers
-1901X (manufactured by Shell Kagaku) and the like can be mentioned.

The polyurethane elastomer is a rubber-like elastic material having a urethane bond --NHCO--O-- in its main chain, and is obtained by reacting a polyester polyol with a diisocyanate compound. A typical example of the polyester-based polyol is an ester of 1,4-butanediol and adipic acid containing a hydroxyl group at the terminal. Specific examples of the diisocyanate compound include MDI (4,4′-diphenylmethane diisocyanate), TDI (tolylene diisocyanate),
1,5-naphthalene diisocyanate and the like can be mentioned.
Examples of commercially available polyurethane-based elastomers include Urethane E3095A manufactured by Toyobo Co., Ltd. and Desmopan 590 manufactured by Bayer Japan Co., Ltd.

The polyamide elastomer is a block copolymer composed of a hard segment of a polyamide component such as polyundecane amide (nylon 11) and polydodecane amide (nylon 12) and a soft segment of a polyether component or an aliphatic polyester component. An example is a coalesced elastomer. Specific examples of the polyether soft segment component include polyethers represented by — (OR) _n — (R is an alkylene group having 2 to 12 carbon atoms), and specific examples of the aliphatic polyester segment component include polycaprolactone and Alkylene glycol HO-R'-OH (R 'is an alkylene group having 2 to 12 carbon atoms) and di- or tricarboxylic acid (R〃)-(COO
H) _2-3 (R 〃 is an alkylene group having 2 to 12 carbon atoms). The commercially available polyamide elastomer is Grillamide ELY-2742.
(Manufactured by EMS CHEMIE), Pebax 6333-
SN00 (made by Toray) is mentioned.

As the polyester-based elastomer, a block copolymer elastomer comprising a hard segment of polyalkylene terephthalate such as polyethylene terephthalate or polybutylene terephthalate and a soft segment of the same polyether component or aliphatic polyester component as described above is used. Can be mentioned. As the polyolefin-based elastomer, ethylene-propylene copolymer,
Examples thereof include ethylene-butene copolymers and ethylene-propylene-diene copolymers.

In the resin composition of the present invention, the mixing ratio of the PAS resin and the thermoplastic elastomer is from 50 to 50.
50 to 1 wt% of thermoplastic elastomer to 99 wt%
Range, preferably 70-95% by weight of PAS resin
On the other hand, the thermoplastic elastomer is in the range of 30 to 5% by weight. When the thermoplastic elastomer is less than 1% by weight, the effect of improving the impact resistance, elongation and flexibility of the resin is small, and when the thermoplastic elastomer exceeds 50% by weight, the strength, heat resistance and rigidity of the PAS resin itself are significantly impaired. Be done.

The aromatic maleimide compound used in the present invention is roughly classified into the compound represented by the general formula (1) and the compound represented by the general formula (2). In the general formula (1), R ₁ is a phenylene group or a divalent organic group containing a phenylene group having a substituent. Examples of such an organic group include a divalent organic group represented by the following formula.

[0025]

[Chemical 7] X in the above organic group is a direct bond or a divalent group represented by the following formula.

[0026]

[Chemical 8] In addition, Y ₁ to Y ₈ in the above organic group is an alkyl group having 1 to ₈ carbon atoms or hydrogen, and at least one of Y ₁ to Y ₈ in each radical corresponding to R ₁ is an alkyl group. is there.

In the aromatic maleimide compound represented by the general formula (2), R ₂ is a divalent hydrocarbon group, preferably an alkylene group having 1 to 8 carbon atoms, and n is 0,
1 or 2. Specific examples of the aromatic maleimide compound represented by the general formula (1) include p-phenylene bismaleimide, m-phenylene bismaleimide, (2-methyl) m-phenylene bismaleimide, 4,4′-diphenyl ether bismaleimide. , 4,4'-diphenyl sulfide bismaleimide, 4,4'-diphenyl sulfone bismaleimide, 4,4'-diphenylmethane bismaleimide, 3,3'-diphenyl ether bismaleimide, 3,3'-diphenyl sulfide bismaleimide, 3 , 3'-diphenyl sulfone bismaleimide,
3,3'-diphenylmethane bismaleimide, 4,4 '
-(2-dimethyl) diphenylmethane bismaleimide,
4,4 '-(2-dimethyl) diphenyl ether bismaleimide, 4,4'-biphenylene bismaleimide,
4,4'-diphenylisopropylidene bismaleimide, 3,4'-diphenyl isopropylidene bismaleimide, 1,4-bis (maleimido-4'-phenoxy)
Phenylene, 1,3-bis (maleimide-4 ″ -phenoxy) phenylene, 4,4′-diphenoxydiphenylsulfone-4 ″ -bismaleimide, 4,4′-bis (maleimide-4 ″ -phenoxy) diphenylsulfone Specific examples of the aromatic maleimide compound represented by the general formula (2) include R ₂ in the general formula (2):
Examples thereof include CH ₂ — and —C ₂ H ₄ —. These may be used alone or in combination of two or more.

The aromatic maleimide compound has an effect of remarkably improving the compatibility between the PAS resin and the thermoplastic elastomer. In order to achieve this effect, the compounding ratio of the aromatic maleimide to the resin mixture of the PAS resin and the thermoplastic elastomer is 0.
It is 1 to 10 parts by weight, preferably 0.5 to 5 parts by weight.
If the amount of the aromatic maleimide is less than 0.1 part by weight, the compatibility improving effect is small, and if the amount of the aromatic maleimide exceeds 10 parts by weight, the resin composition thickens and the moldability deteriorates.

In the PAS resin composition of the present invention, in order to improve strength, heat resistance, rigidity and dimensional stability,
Reinforcing fibers and / or inorganic fillers can be included. Examples of the reinforcing fiber include glass fiber, carbon fiber such as polyacrylonitrile-based and pitch-based, graphite fiber, potassium titanate fiber, silicon carbide fiber, asbestos fiber, ceramic fiber, stainless fiber and other inorganic metal fibers and aromatic polyamide (aramid). ) Examples include organic fibers such as fibers. As the inorganic filler, kaolin, clay, bentonite, zeolite, mica, mica, talc, wollastonite, ferrite, calcium silicate, calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, molybdenum dioxide, graphite, gypsum, glass , Beads, glass balloons and the like. If necessary, the surface of these reinforcing fibers and the inorganic filler can be used after being pretreated with a coupling agent such as a silane type, titanate type or aluminate type.

The blending amount of the reinforcing fiber and the inorganic filler is P
5 to 100 parts by weight and 5 to 80 parts by weight, respectively, are preferable based on 100 parts by weight of the resin mixture consisting of the AS resin and the thermoplastic elastomer.

The resin composition of the present invention is characterized mainly in that it contains molybdenum disulfide (MoS ₂ ). By adding molybdenum disulfide, excellent slidability can be imparted without deteriorating various properties of the non-added resin composition, particularly compatibility and toughness of resin components. The molybdenum disulfide used preferably has an average particle size of 0.1 to 5.0 μm in view of its sliding characteristics.

The compounding amount of molybdenum disulfide is 0.1 with respect to a total weight of 100 parts by weight of a mixture of a PAS resin and a thermoplastic elastomer, an aromatic maleimide compound and optional reinforcing fibers and / or inorganic fillers. ~ 35
Parts by weight, preferably 0.5 to 20 parts by weight.

The resin composition of the present invention contains a heat stabilizer, an ultraviolet absorber, a foaming agent, a flame retardant, a colorant, a release agent, a gas adsorbent, etc. within a range that does not hinder the achievement of the object of the present invention. It can be done.

The resin composition of the present invention is generally in the form of pellets and is mainly used as a raw material for injection molding and extrusion molding. The production method of pellets is not particularly limited, but PAS resin, thermoplastic elastomer, aromatic maleimide compound and molybdenum disulfide are dry-mixed in advance with a mixer such as a tumbler type mixer or a Henschel mixer, and then PAS resin A typical method is to melt-knead in a single-screw or twin-screw extruder at a temperature equal to or higher than the melting point, and then extrude and cut into pellets. The melt-kneading temperature in this case is a temperature equal to or higher than the melting point of the PAS resin, that is, 285 ° C. to 380 ° C., preferably 290.
˜340 ° C. The timing of adding the aromatic maleimide compound, molybdenum disulfide, the inorganic filler and the reinforcing fiber is not limited to the above method, either, either before or after mixing the PAS resin and the thermoplastic elastomer, or A method of adding again to the resin mixture after mixing and mixing again can be adopted. The reinforcing fiber is preferably mixed with the resin composition in the kneading process from the middle of the extruder to prevent the damage.

[0035]

INDUSTRIAL APPLICABILITY The resin composition of the present invention has a good resistance to PAS resin without substantially impairing the desirable properties inherent thereto, that is, mechanical properties, heat resistance, chemical resistance and electrical insulation. Has impact resistance, elongation and flexibility,
Further, molybdenum disulfide exhibits excellent sliding characteristics without impairing the compatibility of the resin component provided by the aromatic maleimide compound. In particular, the resin composition of the present invention has a small friction coefficient and its fluctuation under high-speed sliding, and the heat generation is greatly suppressed. Therefore, the resin composition of the present invention has sliding members such as bearings, shaft seals and cams, for example, sliding members for office automation equipment and home appliances, sliding members for automobiles that require heat resistance, and chemical resistance. It is useful as required sliding members for chemical plants.

[0036]

EXAMPLES Hereinafter, the resin composition of the present invention will be specifically described with reference to Examples. As the PAS resin, polyphenylene sulfide resin powder, Topren "T-4" (made by Topren, melt viscosity 900 poise) was used. T-4
Powder, thermoplastic elastomer, aromatic maleimide compound (N, N'-m-phenylene bismaleimide (Ouchi Shinko Chemical Co., Ltd., "Barnock, PM"), molybdenum disulfide (Nichimori A powder), glass fiber chopped strands (Asahi Glass Co., Ltd. 03MA404) was mixed at a ratio shown in Table 1. A styrene / butadiene / styrene block copolymer (SBS) (Asahiprene T manufactured by Asahi Kasei Kogyo Co., Ltd.) was used as a thermoplastic elastomer.
430), SBS hydrogenated product (SEBS) (Asahi Kasei Kogyo Tuftec H1041), and SEBS acid modified product (SEBS-M) (Asahi Kasei Kogyo Tuftec M191).
3) was used. Upon mixing, the respective components were dry blended, and then melt-kneaded at 300 ° C. using a twin-screw extruder to form pellets. The glass fiber was added to the kneaded resin composition in the middle of the extruder.

Each resin composition has a mold temperature of 300 ° C. and a mold temperature of 110.
A test piece for physical property evaluation was prepared by injection molding at ℃, and the physical property was evaluated based on the following criteria. The results are shown in Table 1. Tensile strength: JIS K-7113 (Test speed 5 mm /
Min) Taber index: JIS K-7204 (wear wheel: Taber CS-17, displayed as wear amount (mg) per 1000 revolutions) Limit PV value: JIS K-7218, method A (V: 80c)
m / sec, P: arbitrary, friction distance: 1500 m, contact area:
2 cm ² )

[0038]

[Table 1]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication C08L 23/00 LCQ 7107-4J 53/02 LLZ 7142-4J 67/02 LPK 8933-4J 75/04 NGJ 8620-4J 77/00 LQT 9286-4J

Claims (2)

[Claims] 1. (A) Polyarylene sulfide resin 5
0 to 99% by weight, (B) thermoplastic elastomer 50 to 1
100 parts by weight of a resin mixture consisting of 10% by weight, (C) at least one compound 0.1-1 selected from the aromatic maleimide compounds represented by the following general formulas (1) and (2):
0 parts by weight and 0.1 to 35 parts by weight of (D) molybdenum disulfide (based on a total of 100 parts by weight of the three components (A), (B), and (C) above). Arylene sulfide resin composition. [Chemical 1] In the formula (1), R ₁ is a divalent organic group containing a phenylene group or a phenylene group having a substituent. [Chemical 2] In the formula (2), R ₂ is a divalent hydrocarbon group and n is 0, 1 or 2. 2. A polyarylene sulfide resin (A) 5
0 to 99% by weight, (B) thermoplastic elastomer 50 to 1
100 parts by weight of a resin mixture consisting of 10% by weight, (C) at least one compound 0.1 to 1 selected from aromatic maleimide compounds represented by the following general formulas (1) and (2).
0 parts by weight, (E) 5 to 100 parts by weight of reinforcing fiber and / or 5 to 80 parts by weight of inorganic filler, and (D) molybdenum disulfide [above (A), (B), (C), (E) Based on a total of 100 parts by weight of the components] 0.1 to 35 parts by weight, and a polyarylene sulfide resin composition.