JP2001064503A - Thermoplastic resin composition, method for producing the same, and pump component - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To contain polyphenylene ether resin, polystyrene resin and glass fiber as essential components, and to have excellent general mechanical properties such as flexural strength, tensile strength and impact resistance, and fluidity, and Provided are a thermoplastic resin composition having excellent fatigue resistance against repeated stress, a method for producing the same, and a pump component using the thermoplastic resin composition. SOLUTION: This is a thermoplastic resin composition containing the following component (A) 5 to 94% by weight, component (B) 5 to 94% by weight, and component (C) 1 to 50% by weight, and has a temperature of 330 to 3
A thermoplastic resin composition obtained by kneading at 70 ° C. (A): Polyphenylene ether resin (B): Polystyrene resin (C): Glass fiber

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition, a method for producing the same, and a pump component.
More specifically, the present invention contains polyphenylene ether-based resin, polystyrene-based resin and glass fiber as essential components, has excellent general mechanical properties such as bending strength, tensile strength and impact resistance, and excellent fluidity, and can be repeatedly used. The present invention relates to a thermoplastic resin composition having excellent fatigue resistance to stress, a method for producing the same, and a pump component using the thermoplastic resin composition.

[0002]

2. Description of the Related Art Polyphenylene ether-based resin compositions composed of polyphenylene ether-based resins, particularly polystyrene-based resins, are used in various fields because of their excellent mechanical properties, thermal properties and water resistance. It is used as a material for parts around water such as tanks and plumbing parts. Pump components are required to be excellent in general mechanical properties such as bending strength, tensile strength and impact resistance, and also excellent in fatigue resistance against repeated stress. In particular, the pump component is used in an environment subjected to severe repetitive stress due to its properties, so it is an essential condition that the pump component has excellent fatigue resistance. In order to obtain a resin composition having excellent fatigue resistance, a technique of adding glass fiber to a polyphenylene ether-based resin having excellent mechanical properties at a ratio according to the purpose is well known, and the production is performed by resin. In order to suppress the decomposition of the components, the temperature is set to give a necessary minimum heat to the resin, and in order to maintain the strength, the kneading is performed under a kneading condition in which the glass fiber length does not become short. However, these methods can provide a certain degree of fatigue resistance, but have a problem that they are not sufficient when higher fatigue resistance is required. In addition, the above-mentioned kneading method has a problem that a product having excellent fluidity cannot be obtained, and the fluidity during molding processing is insufficient.

[0003]

Under these circumstances, the problem to be solved by the present invention is to contain a polyphenylene ether-based resin, a polystyrene-based resin and glass fiber as essential components, and to provide a flexural strength, a tensile strength and a tensile strength. In providing a thermoplastic resin composition having excellent general mechanical properties and fluidity such as impact resistance, and excellent fatigue resistance to repeated stress, a method for producing the same, and a pump component using the thermoplastic resin composition. It exists.

[0004]

That is, the first aspect of the present invention provides the following component (A) of 5 to 94% by weight, component (B) of 5 to 94% by weight and component (C) of 1 to 50% by weight. A thermoplastic resin composition containing 3% by weight;
It relates to a thermoplastic resin composition obtained by kneading at 70 ° C. (A): polyphenylene ether-based resin (B): polystyrene-based resin (C): glass fiber Further, the second invention of the present invention relates to the above-mentioned component (A) 5.
A method for producing a thermoplastic resin composition comprising -94% by weight of a component (B), 5 to 94% by weight of a component (B) and 1 to 50% by weight of a component (C). ~
The present invention relates to a method for producing a thermoplastic resin composition to be kneaded at 370 ° C. A third invention of the present invention relates to a pump component using the thermoplastic resin composition of the first invention.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The component (A) of the present invention is a polyphenylene ether resin, and a known resin can be used.
The polyphenylene ether-based resin is a general term for a polymer represented by the following general formula, and may be a single polymer or a copolymer of two or more polymers. (Wherein, R _{1 to} R ₄ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, and a haloalkyl group or haloalkoxy having at least two carbon atoms between the halogen atom and the phenyl ring. Tertiary α-
Represents a monovalent substituent selected from those not containing carbon,
Is an integer representing the degree of polymerization. )

As a preferred specific example of the polyphenylene ether resin, in the above general formula, R ₁ and R ₂ are an alkyl group having 1 to 4 carbon atoms, and R ₃ and R ₄ are a hydrogen atom or a carbon atom having 1 carbon atom. And alkyl groups 4 to 4, specifically, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, Poly (2-methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) Ether, poly (2-ethyl-6-propyl-1,
4-phenylene) ether and the like. Examples of the polyphenylene ether-based copolymer include copolymers in which the above-mentioned polyphenylene ether repeating unit partially contains an alkyl trisubstituted phenol, for example, 2,3,6-trimethylphenol. Further, a copolymer in which a styrene-based compound is grafted on these PPEs may be used. As the styrene-based compound-grafted polyphenylene ether, styrene, α
-A copolymer obtained by graft polymerization of methylstyrene, vinyltoluene, chlorostyrene and the like.

The component (A) of the present invention is a polyphenylene ether-based resin. The polyphenylene ether-based resin modified with an unsaturated acid such as maleic anhydride is used in whole or in part, and the rest is unmodified polyphenylene ether-based resin. A system resin may be used.

The component (B) of the present invention is a polystyrene resin. Known polystyrene resins can be used, and those having at least 25% by weight or more of a repeating structural unit derived from an aromatic vinyl compound represented by the following general formula in the polymer are preferable. (Wherein, R ₅ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Z represents a halogen atom or a substituent being an alkyl group having 1 to 4 carbon atoms, and a is an integer of 0 to 5) Is)

Examples of the styrene-based polymer include a homopolymer of styrene or a derivative thereof (for example, p-methylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, chlorostyrene, bromostyrene, etc.); For example, polybutadiene, styrene-butadiene block copolymer, partially hydrogenated product thereof, styrene-isoprene block copolymer, partially hydrogenated product thereof, polyisoprene, butyl rubber, EPDM, ethylene-propylene copolymer, natural rubber and the like Styrene-based copolymers obtained by modifying an elastomer substance alone or with a mixture thereof, and styrene-based copolymers such as styrene-butadiene random and block copolymers, partially hydrogenated products thereof, styrene-isoprene random and block copolymers Polymer, its partially hydrogenated product, Tylene-acrylonitrile copolymer (SAN), styrene-methyl methacrylate copolymer (MS resin), styrene-methyl methacrylate-
Butadiene copolymer (MBS), styrene-acrylonitrile-butadiene copolymer (ABS) and the like. In particular, as the component (B) of the present invention, high impact polystyrene (HIPS) produced using polybutadiene or a styrene-butadiene block copolymer is preferable because of its excellent fatigue resistance.

The component (C) of the present invention is a glass fiber. Known glass fiber types can be used, such as E glass, C glass, A glass, and S glass.
Glass and the like can be given. The average diameter of the glass fiber used is usually 5 to 20 μm, preferably 6 to 15 μm.
μm. If the average fiber diameter is less than 5 μm, the fibers may be damaged during the production or molding of the composition, and the fatigue resistance of the molded article may be reduced. On the other hand, if the fiber diameter exceeds 20 μm, the appearance of the molded article is poor. May be. The average fiber length of the glass fibers is 150 to 5 in the thermoplastic resin composition.
00 μm, more preferably 200 μm.
４００400 μm. If the average fiber length is less than 150 μm, mechanical properties such as fatigue resistance and bending strength may be reduced. On the other hand, if the fiber length exceeds 500 μm, the fluidity in the mold may be reduced or the molded product may be deteriorated. The appearance may deteriorate.

As the glass fiber, a fiber whose surface has been treated with a sizing agent can be used. As the type of the sizing agent, generally, there are aromatic urethane type, aliphatic urethane type, acrylic type, etc., and an aromatic urethane type sizing agent is preferable. Other sizing agents do not have good adhesiveness to the resin, so that the mechanical strength of the resin composition may decrease.

The glass fibers are preferably surface-treated with a silane coupling agent. The silane coupling agent has an organic functional group that reacts with the resin. Examples of the organic functional group include an amino group, an epoxy group, a methacryl group,
Examples thereof include a vinyl group and a mercapto group, and preferred are an amino group and an epoxy group.

The proportion of each component in the thermoplastic resin composition of the present invention is (A) 5 to 94% by weight, and (B) 5 to 9% by weight.
4% by weight and (C) 1 to 50% by weight, preferably (A) 10 to 80% by weight, (B) 15 to 85% by weight and (C) 5 to 45% by weight. If the content of (A) is too small, the fatigue resistance and heat resistance will be insufficient, while if the content of (A) is too large, the fluidity will decrease and the moldability will become a problem. If the content of (B) is too small, the fluidity is reduced and the formability becomes problematic. On the other hand, if the content of (B) is too large, mechanical properties such as fatigue resistance and bending strength and heat resistance are insufficient. If (C) is too small, mechanical properties such as fatigue resistance and flexural strength will be insufficient, while if (C) is too large, fluidity will be reduced and moldability will be a problem. In addition, take-up at the time of manufacturing becomes a problem.

[0014] The thermoplastic resin composition of the present invention may contain an elastomer for the purpose of imparting impact resistance. The elastomer is a natural and synthetic rubbery material that is elastic at room temperature. Specific examples thereof include natural rubber, butadiene polymer, isoprene polymer, chlorobutadiene polymer, butadiene-acrylonitrile copolymer, isobutylene polymer, isobutylene-butadiene copolymer, isobutylene-isoprene copolymer, and acrylic acid ester. Polymer, ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene copolymer, thioco-
Rubber, polysulfide rubber, polyurethane rubber, polyether rubber (eg, polypropylene oxide), epichlorohydrin rubber, styrene-butadiene copolymer having a styrene content of less than 25% by weight, a partially hydrogenated product thereof, styrene-isoprene copolymer. Examples thereof include polymers and partially hydrogenated products thereof. These rubbery substances may be produced by any polymerization method (for example, emulsion polymerization, solution polymerization) and any catalyst (for example, peroxide, trialkylaluminum, lithium halide, nickel-based catalyst). Further, those having various degrees of crosslinking and those having various proportions of microstructure (for example, cis structure, trans structure, vinyl group, etc.) are also used. As the copolymer, any of various copolymers such as a random copolymer, a block copolymer, and a graft copolymer can be used.
Further, a partially modified rubbery substance can be used,
For example, hydroxy or carboxy-terminal modified polybutadiene and the like can be mentioned.

The thermoplastic resin composition of the present invention may contain, in addition to the above components, other additives commonly used during kneading and molding of the resin according to the purpose, as long as the physical properties are not impaired. Flame retardants, pigments, dyes, reinforcing agents (such as carbon fiber), other fillers, heat-resistant agents, weathering agents, lubricants, mold release agents, crystal nucleating agents, plasticizers, flow improvers, antistatic agents, stabilizers Etc. can be added. The stabilizer is not particularly limited, and includes all conventional stabilizers. The stabilizer includes a heat stabilizer, an antioxidant, a light stabilizer, and a polymerization inhibitor.

The conditions for the production of the thermoplastic resin of the present invention are as follows.
It is essential to knead at 370 ° C. More preferably, it is 340-365 ° C. If the temperature is lower than 330 ° C., the adhesiveness between the resin and the glass fiber interface is insufficient, and sufficient fatigue resistance cannot be obtained. On the other hand, if the temperature exceeds 370 ° C., sufficient fatigue resistance cannot be obtained due to decomposition of the polystyrene resin. Here, the temperature is an actually measured resin temperature obtained by inserting the sensor tip of a resin thermometer into the resin immediately after being extruded from the die head hole of the kneader and measuring the temperature.

The kneading apparatus for production is not particularly limited, and examples of the apparatus include a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roller, a kneader, and the like. Drive to Among the kneading apparatuses described above, a twin-screw extruder having a plurality of raw material input ports is preferable. The order of mixing the components is not particularly limited, but it is generally preferable to knead the components other than the glass fibers and then knead the glass fibers.

Examples of the method for producing a molded article from the PPE resin composition of the present invention include, but are not limited to, injection molding, extrusion molding, blow molding, press molding and the like.

The composition of the present invention is suitably used for applications requiring fatigue resistance. For example, pumps, tanks, plumbing, and other plumbing components exposed to fluctuating pressure, pneumatic components such as joints, connectors exposed to repeated vibration and stress, fan shrouds,
Spoilers, speaker brackets and the like.

[0020]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. [I] The components used and their abbreviations are as follows. (A) PPE: poly (2,6-dimethyl-) having an intrinsic viscosity of 0.46 dl / g measured in chloroform at 30 ° C.
(1,4-phenylene ether) (B) GF: glass fiber TP3 manufactured by Nippon Sheet Glass
5 (grade), fiber diameter 10 μm, fiber length 3 mm, glass surface treated with aromatic urethane sizing agent and aminosilane (C) HIPS: high impact polystyrene HIPS-1: H554 (grade) manufactured by Nippon Polystyrene. Rubber content: 7.0 wt%, weight average molecular weight: 23.2 × 10 ⁴ , MI: 3.0 g / 10 min under measurement conditions of 200 ° C. and 49 N load HIPS-2: H548 (grade) manufactured by Nippon Polystyrene Co., Ltd. . Rubber content is 9.0 wt%, weight average molecular weight is 21.5 × 10 ⁴ , MI is 3.2 g / 10 min under the measurement conditions of 200 ° C. and 49N load. (D) Carbon black CB-1: Masterbatch, SHPA manufactured by Kakara
817 (grade), carbon black amount 45% by weight,
Dispersant 55% by weight, CB-2: Carbon black # 750 manufactured by Mitsubishi Chemical Corporation
B (grade), average particle size 18 μm

[II] The evaluation method is as follows. (1) Tensile Properties According to ASTM D638, the tensile yield strength at 23 ° C. was measured using a test piece having a thickness of ８ inch. (2) Bending Characteristics According to ASTM D790, the bending elastic modulus and the bending strength at 23 ° C. were measured using a 1 / 8-inch thick test piece. (3) Impact Strength A notched Izod impact strength at 23 ° C. was measured using a イ ン チ inch thick test piece in accordance with ASTM D256. (4) Heat deformation temperature According to ASTM D648, a 1/4 inch thick test piece was used to measure the heat deformation temperature under a load of 1.81 MPa. (5) Melt flow rate In accordance with ASTM D1238, the pellets after kneading and granulation were dried in a hot air oven at 100 ° C. for 2 hours, and then the melt flow rate at 280 ° C. under a load of 98 N was measured. (6) Fatigue resistance After the test piece wound with the bleach is left in hot water for 2 hours, a uniform bending fatigue test is carried out at 23 ° C. while impregnating the bleach with water, and the number of repetitions up to breaking is measured. did. Testing machine: Servo pulser EHF-FB manufactured by Shimadzu Corporation
1 Test piece: JIS K 7118 II-40 type test piece
3.2 mm thickness Bending stress: 0 to 85.8 MPa, cycle: 2 times / sec, waveform: sine wave (7) Glass fiber length After melt-kneading, the pelletized pellets were measured for glass fiber length. The following method was used for the measurement. The pellets are placed in a crucible and burned in an electric furnace at 550 ° C. for 1 hour to separate a resin component and residual glass fibers. The remaining glass fiber was dropped on a preparation, and ethyl alcohol was further dropped and dispersed. A photograph was taken with a microscope, and the glass fiber length was measured on the photograph to determine the number average fiber length. Further, the distribution of the glass fiber length is 500 μm with respect to the total number of glass fibers.
The ratio of the number of the above glass fibers was determined.

Examples 1 to 3 and Comparative Examples 1 to 3 A mixture of (A) PPE, (C) HIPS and (D) CB is provided from the first hopper, and (B) GF is provided downstream of the first hopper. The mixture was charged into the twin-screw kneader at the mixing ratio shown in Tables 1 and 2 from the second hopper, and was melt-kneaded under the kneading conditions shown in Tables 3 and 4, and granulated to obtain a polyphenylene ether-based resin composition. In Tables 3 and 4, the first zone of the cylinder set temperature indicates the area from the first hopper to the side before the second hopper, and the second zone indicates the area from the second hopper to the die head. One of the following three kinds of kneaders was used. These are abbreviated as TEM50, PCM60, and PCM80, respectively. Apparatus: Toshiba Machine Co., Ltd., 3-section type twin screw kneader TE
M50A Ikegai Co., Ltd., twin-type twin screw kneader PCM60 Ikegai Co., Ltd., double-type twin screw kneader PCM80 The screw shape is the kneading part immediately after the resin input from the first hopper, and the glass fiber input from the second hopper. The kneading section immediately after was a combination of a reverse screw and a kneading disk. The resin temperature was measured by adding a resin thermometer DP-R manufactured by Rika Kogyo Co., Ltd. to the resin immediately after being extruded from the die head hole of the kneader.
350 sensor tips were inserted and measured. The obtained composition was injection molded at 280 ° C. using an injection molding machine IS100EN manufactured by Toshiba Machine Co., Ltd. to prepare an ASTM test piece. Further, a fatigue test piece was prepared at 280 ° C. using a Cycap 110/50 injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. The prepared test pieces were evaluated for general physical properties and fatigue resistance. The melt flow rate and glass fiber length of the melt-kneaded and granulated composition before injection molding were measured. Table 2 shows the conditions and results.

The following can be seen from the results. All examples satisfying the conditions of the present invention show satisfactory results in all evaluation items. On the other hand, Comparative Examples 1 and 2 of the conventional kneading method are inferior in fluidity and fatigue resistance, and Comparative Example 3 is inferior in fatigue resistance.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

[Table 4]

[0028]

As described above, according to the present invention, polyphenylene ether-based resin, polystyrene-based resin and glass fiber are contained as essential components, and general mechanical properties such as bending strength, tensile strength and impact resistance and flow resistance are obtained. A thermoplastic resin composition having excellent heat resistance and excellent fatigue resistance to repeated stress, a method for producing the same, and a pump component using the thermoplastic resin composition can be provided.

Continued on the front page F-term (reference) 4F070 AA08 AA52 AB08 AB11 AC28 AD02 AE01 FA03 FC02 FC05 FC06 FC07 4F071 AA10 AA12X AA22 AA22X AA51 AA75 AA76 AA77 AB28 AD01 AE17 AF15 AF17 AF23 AF57 AH17 BB03 BC03 BC06 BC08 BC03 BC03 BC03 BC03 BC03 BC08 BN02X BN06X BN14X BN15X BN16X BN18W BN21X BP01X CH07W DL006 FA046 FB106 FB136 FB146 FB156 FB266 FD010 FD016 FD020 FD030 FD090 FD100 FD130 FD160 FD170

Claims (4)

[Claims] 1. A thermoplastic resin composition comprising the following components (A) in an amount of 5 to 94% by weight, component (B) in an amount of 5 to 94% by weight and component (C) in an amount of 1 to 50% by weight. ~ 3
A thermoplastic resin composition obtained by kneading at 70 ° C. (A): Polyphenylene ether resin (B): Polystyrene resin (C): Glass fiber 2. The thermoplastic resin composition according to claim 1, wherein the average fiber length of the glass fibers (C) in the thermoplastic resin composition is 150 to 500 μm. 3. The composition according to claim 1, wherein the component (A) is 5 to 94% by weight, the component (B) is 5 to 94% by weight, and the component (C) is 1 to 50%.
What is claimed is: 1. A method for producing a thermoplastic resin composition containing 0.1% by weight, comprising kneading components (A) to (C) at a temperature of 330 to 370 ° C. 4. A pump component using the thermoplastic resin composition according to claim 1.