KR102132804B1 - Liquid-crystalline resin composition for sliding-resistant wear member and sliding-resistant wear member using the same - Google Patents

Abstract

Provided is a liquid crystal resin composition for a wear resistant wear member and a wear resistant wear member using the same, which are used to manufacture a wear resistant wear member having reduced sliding wear while having the same adhesiveness and impact resistance as the prior art .
The liquid crystal resin composition for sliding wear-resistant members according to the present invention contains (A) a liquid crystal resin, (B) talc, and (C) an epoxy group-containing copolymer, and the central diameter of the (B) talc is 50 μm. Below, content of the said (C) epoxy group containing copolymer is 2.0-6.5 mass %.

Description

Liquid-crystalline resin composition for sliding-resistant wear member and sliding-resistant wear member using the same

The present invention relates to a liquid crystal resin composition for a wear resistant member, and a wear resistant member using the same.

The liquid crystal resin represented by the liquid crystal polyester resin has excellent mechanical strength, heat resistance, chemical resistance, electrical properties, and the like, and has excellent dimensional stability, and thus is widely used as a high-performance engineering plastic. In recent years, liquid crystal resins have been utilized for precision equipment parts by taking advantage of these characteristics.

As a component in which a liquid crystalline resin is used, For example, connectors, such as an FPC connector; Sockets such as memory card sockets; Parts for camera modules such as lens holders; Relay. Since these parts must have excellent adhesiveness and impact resistance, and may be used in a form in which two or more members are in dynamic contact, sliding wear resistance (ie, when two or more members are in dynamic contact) It is also required that the abrasion property) is reduced. For example, Patent Document 1, as a subject, is to provide a molded article made of a liquid crystal resin composition having excellent surface appearance and excellent sliding property, and containing a liquid crystal resin and talc having a specific volume average particle diameter in a specific ratio. A liquid crystal resin composition is disclosed.

Patent Document 1: Japanese Patent No. 5087958

However, according to the studies of the present inventors, with the conventional liquid crystal resin composition, the reduction in sliding wear resistance is insufficient. The present invention has been made to solve the above problems, the purpose of which, while having the same adhesiveness and impact resistance as the prior art, is a liquid crystal for a sliding wear-resistant member used to manufacture a sliding wear-resistant member with reduced sliding abrasion resistance It is to provide a resin composition and a sliding wear resistant member using the same.

The present inventors have repeatedly studied in order to solve the above problems. As a result, it was found out that the above problem can be solved by using a liquid crystal resin composition containing a liquid crystal resin, a talc having a specific center diameter, and an epoxy group-containing copolymer, and the content of the epoxy group-containing copolymer being within a predetermined range. The invention has been completed. More specifically, the present invention provides the following.

(1) (A) containing a liquid crystal resin, (B) talc, and (C) an epoxy group-containing copolymer, the central diameter of the (B) talc is 50 µm or less, and (C) the epoxy group-containing copolymer The content of the liquid crystal resin composition for sliding wear-resistant members is 2.0 to 6.5% by mass.

(2) The composition according to (1), wherein the content of the (B) talc is 25 to 45% by mass.

(3) A sliding wear-resistant member comprising the composition according to (1) or (2).

When the liquid-resistant resin composition for a wear-resistant wear-resistant member of the present invention is used as a raw material, a wear-resistant wear-resistant member having reduced adhesion and abrasion resistance can be obtained while having the same adhesiveness and impact resistance as the prior art.

In FIG. 1, (a) is a diagram for explaining a method for preparing a sample for evaluating epoxy adhesion, and (b) is a diagram for explaining a method for evaluating epoxy adhesion.
2 is a view for explaining a test piece for evaluation of mold deposit (MD).
3 is a view for explaining a sliding wear amount evaluation method.

Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments.

<Liquid crystal resin composition for sliding resistant wear member>

The liquid crystal resin composition for wear-resistant wear-resistant members of the present invention contains (A) a liquid crystal resin, (B) talc, and (C) an epoxy group-containing copolymer.

[(A) Liquid crystalline resin]

The (A) liquid crystalline resin used in the present invention refers to a melt-processable polymer having properties capable of forming an optically anisotropic molten phase. The properties of the anisotropic molten phase can be confirmed by a conventional polarization test method using an orthogonal polarizer. More specifically, the anisotropic melting phase can be confirmed by using a Leitz polarization microscope to observe the molten sample placed on the Leitz hot stage at a magnification of 40 times under a nitrogen atmosphere. When the liquid crystal polymer applicable to the present invention is inspected between orthogonal polarizers, polarized light is normally transmitted through optical polarization even when, for example, in the state of melting stop.

The type of the liquid crystal resin (A) as described above is not particularly limited, and is preferably aromatic polyester and/or aromatic polyesteramide. Moreover, the polyester which partially contains aromatic polyester and/or aromatic polyesteramide in the same molecular chain is also in the range. (A) As the liquid crystalline resin, when dissolved in pentafluorophenol at a concentration of 0.1% by mass at 60°C, the logarithmic viscosity of preferably at least about 2.0 dl/g, more preferably 2.0 to 10.0 dl/g ( IV) is preferably used.

The aromatic polyester or aromatic polyesteramide as the (A) liquid crystal resin applicable to the present invention is particularly preferably at least selected from the group consisting of aromatic hydroxycarboxylic acid, aromatic hydroxyamine, and aromatic diamine. It is an aromatic polyester or aromatic polyesteramide which has a repeating unit derived from one type of compound as a constituent component.

More specifically,

(1) Polyester consisting mainly of repeating units derived from one or two or more of aromatic hydroxycarboxylic acid and its derivatives;

(2) Mainly (a) repeating units derived from one or two or more of aromatic hydroxycarboxylic acids and derivatives thereof, and (b) one of aromatic dicarboxylic acids, alicyclic dicarboxylic acids, and derivatives thereof, or A polyester composed of a repeating unit derived from two or more kinds, and (c) a repeating unit derived from at least one or two or more kinds of aromatic diols, alicyclic diols, aliphatic diols, and derivatives thereof;

(3) a repeating unit mainly derived from (a) one or two or more of aromatic hydroxycarboxylic acid and its derivatives; and (b) one or two or more of aromatic hydroxyamine, aromatic diamine, and derivatives thereof. A polyester amide comprising a repeating unit derived from, and (c) a repeating unit derived from one or two or more of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof;

(4) Mainly (a) repeating units derived from one or two or more of aromatic hydroxycarboxylic acid and derivatives thereof, and (b) one or two or more of aromatic hydroxyamine, aromatic diamine, and derivatives thereof Repeating units derived from, (c) repeating units derived from one or two or more of aromatic dicarboxylic acid, alicyclic dicarboxylic acid, and derivatives thereof, (d) aromatic diol, alicyclic diol, aliphatic diol And repeating units derived from at least one or two or more of these derivatives, polyesteramides, and the like. Moreover, a molecular weight modifier can be used together with the said component as needed.

Preferable examples of the specific compound constituting the liquid crystal resin (A) applicable to the present invention include aromatic hydroxycarboxylic acids such as p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, 2,6 -Dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl, hydroquinone, resorcin, a compound represented by the following general formula (I), and the following general formula (II) Aromatic diols such as compounds represented by ); Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 4,4'-diphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and compounds represented by the following general formula (III); and aromatic amines such as p-aminophenol and p-phenylenediamine.

(X: is a group selected from alkylene (C ₁ ~ C ₄ ), alkylidene, -O-, -SO-, -SO ₂ -, -S-, and -CO-)

(Y: a group selected from -(CH ₂ ) _n -(n=1-4) and -O(CH ₂ ) _n O-(n=1-4).)

The preparation of the liquid crystal resin (A) used in the present invention can be carried out by a known method using a direct polymerization method or a transesterification method from the above-mentioned monomer compound (or a mixture of monomers). The slurry polymerization method or the like is used. The above-mentioned compounds having an ester-forming ability may be used for polymerization in an intact form, and may also be modified with a derivative having the corresponding ester-forming ability from a precursor before the polymerization. When polymerizing these, various catalysts can be used, and typical examples thereof include dialkyl tin oxide, diaryl tin oxide, titanium dioxide, alkoxy titanium silicates, titanium alcoholates, alkali and alkaline earth metal salts of carboxylic acid, And Lewis acid salts such as BF ₃ . The catalyst is generally used in an amount of about 0.001 to 1% by mass, particularly about 0.01 to 0.2% by mass, relative to the total mass of the monomer. When further required, the polymer produced by these polymerization methods can increase the molecular weight by reducing pressure or heating in an inert gas by solid phase polymerization.

The melt viscosity of the liquid crystal resin (A) obtained by the above method is not particularly limited. Generally, a melt viscosity at a molding temperature of 10 MPa or more and 600 MPa or less can be used at a shear rate of 1000 sec ^-1 . However, an excessively high viscosity by itself is not preferable because the fluidity deteriorates very much. The liquid crystal resin (A) may be a mixture of two or more liquid crystal resins.

In the liquid crystal resin composition of the present invention, the preferred content of the liquid crystal resin (A) is 38.5 to 83% by mass. When the content of the component (A) is 38.5% by mass or more, it is preferable from the viewpoint of fluidity, and the content of the component (A) is 83% by mass or less from the viewpoint of heat resistance. Moreover, content of (A) component is more preferably 44-77.5 mass %, More preferably, it is 50-72 mass %, Especially preferably, it is 55-67 mass %.

[(B) Talc]

(B) Talc is used in combination with the (C) epoxy group-containing copolymer to improve the adhesion of the molded article obtained from the liquid crystal resin composition of the present invention, and at the same time contribute to reducing the sliding abrasion of the molded article. (B) Talc can be used singly or in combination of two or more kinds.

(B) The talc has a median diameter of 50 µm or less. When the median diameter exceeds 50 µm, the melt viscosity of the obtained liquid crystal resin composition tends to increase, and when the liquid crystal resin composition is molded, mold deposit (hereinafter, also referred to as "MD") is liable to occur. The central diameter is preferably 10 to 25 µm, more preferably 14 to 23 µm, and still more preferably 17 to 21 µm, in that adhesion is easily improved and melt viscosity and MD are likely to be reduced. . In the present specification, the median diameter refers to a median of volume standards measured by a laser diffraction/scattering particle size distribution measurement method. In addition, a mold deposit means an adherend to a mold in molding.

The content of the component (B) is preferably 15 to 55% by mass in the liquid crystal composition of the present invention. When the content is 15 to 55% by mass, adhesiveness is likely to be improved, and melt viscosity and MD are likely to be reduced. Since the adhesiveness is more easily improved, and the melt viscosity and MD are more likely to be reduced, the content is more preferably 20 to 50% by mass, more preferably 25 to 45% by mass, even more preferably It is 30-40 mass %.

[(C) Epoxy group-containing copolymer]

The liquid crystal composition of the present invention contains (C) an epoxy group-containing copolymer. (C) Epoxy group-containing copolymers can be used singly or in combination of two or more kinds. The (C) epoxy group-containing copolymer is not particularly limited, and examples thereof include at least one selected from the group consisting of (C1) epoxy group-containing olefin copolymers and (C2) epoxy group-containing styrene copolymers. . The 2.0-6.5 mass% (C) epoxy group-containing copolymer contributes to reducing the sliding abrasion property of the molded article obtained from the liquid crystal resin composition of the present invention by using it in combination with (B) talc.

(C1) Examples of the olefin-based copolymer containing an epoxy group include a copolymer composed of repeating units derived from α-olefin and repeating units derived from glycidyl ester of α,β-unsaturated acid.

The α-olefin is not particularly limited, and examples thereof include ethylene, propylene, and butene, and among these, ethylene is preferably used. The glycidyl ester of α,β-unsaturated acid is represented by the following general formula (IV). The glycidyl ester of α,β-unsaturated acid is, for example, acrylic acid glycidyl ester, methacrylic acid glycidyl ester, ethacrylic acid glycidyl ester, itaconic acid glycidyl ester, etc., in particular methacrylic acid Glycidyl esters are preferred.

(C1) In the epoxy group-containing olefin-based copolymer, the content of the repeating unit derived from α-olefin is 87 to 98% by mass, and the content of the repeating unit derived from glycidyl ester of α,β-unsaturated acid is 13 It is preferable that it is -2 mass %.

The (C1) epoxy group-containing olefin-based copolymer used in the present invention is acrylonitrile, acrylic acid ester, methacrylic acid ester, α-methylstyrene, anhydrous as a third component in addition to the above two components, within the scope of not impairing the present invention. A repeating unit derived from one or two or more olefinically unsaturated esters such as maleic acid may be contained in an amount of 0 to 48 parts by mass based on 100 parts by mass of the two components.

The epoxy group-containing olefin-based copolymer (C1) of the present invention can be easily prepared by a conventional radical polymerization method using a monomer and a radical polymerization catalyst corresponding to each component. More specifically, the glycidyl ester of α-olefin and α,β-unsaturated acid is usually present in the presence of a radical generator, 500-4000 atm, 100-300° C. in the presence or absence of a suitable solvent or chain transfer agent. It can be manufactured by a method of copolymerizing under. In addition, it can also be produced by a method of mixing an α-olefin with a glycidyl ester of α,β-unsaturated acid and a radical generator, and melt graft copolymerizing in an extruder.

Examples of the styrene-based copolymer containing an epoxy group (C2) include, for example, a copolymer composed of repeating units derived from styrenes and repeating units derived from glycidyl esters of α,β-unsaturated acids. About the glycidyl ester of (alpha), (beta)-unsaturated acid, since it is the same as what was demonstrated in (C1) component, description is abbreviate|omitted.

Examples of styrenes include styrene, α-methylstyrene, styrene bromide, and divinylbenzene, and styrene is preferably used.

The (C2) epoxy group-containing styrene-based copolymer used in the present invention may be a multi-component copolymer containing a repeating unit derived from one or two or more vinyl monomers as a third component in addition to the above two components. have. What is suitable as a 3rd component is a repeating unit derived from 1 type(s) or 2 or more types of olefinically unsaturated esters, such as acrylonitrile, acrylic acid ester, methacrylic acid ester, and maleic anhydride. A styrene-based copolymer containing an epoxy group containing 40% by mass or less of these repeating units in the copolymer is preferred as the component (C2).

(C2) In the styrene-based copolymer containing an epoxy group, the content of the repeating unit derived from the glycidyl ester of α,β-unsaturated acid is 2 to 20% by mass, and the content of the repeating unit derived from styrene is 80 to It is preferable that it is 98 mass %.

(C2) The epoxy group-containing styrene-based copolymer can be prepared by a conventional radical polymerization method using a monomer and a radical polymerization catalyst corresponding to each component. More specifically, the glycidyl ester of styrene and α,β-unsaturated acid is usually present in the presence of a radical generator, 500-4000 atm, 100-300°C in the presence or absence of a suitable solvent or chain transfer agent. It can be manufactured by a method of copolymerization. Moreover, it can also be manufactured by a method of mixing styrene with glycidyl ester of α,β-unsaturated acid and a radical generator, and melt graft copolymerizing in an extruder.

As the (C) epoxy group-containing copolymer, the (C1) epoxy group-containing olefin copolymer is preferred from the viewpoint of heat resistance. When the component (C1) and the component (C2) are used in combination, the ratio between these components can be appropriately selected according to the required characteristics.

(C) The content of the epoxy group-containing copolymer is 2.0 to 6.5% by mass in the liquid crystal resin composition of the present invention. When the content of the component (C) is within the above range, it is easy to obtain a molded body having reduced sliding abrasion property without impairing fluidity. The content is more preferably 2.5 to 6.0% by mass, and the content is more preferably 3.0 to 5.0% by mass.

[(D) Carbon black]

The carbon black (D) used as an optional component in the present invention is not particularly limited as long as it is generally available for resin coloring. Usually, (D) carbon black contains a lump formed by agglomeration of primary particles, but the resin composition of the present invention is not contained unless a significant amount of lumps having a size of 50 µm or more is contained. It is difficult to generate many boots (fine millet-like protrusions (fine irregularities) in which carbon black is aggregated) on the surface of the molded body formed by molding. When the content of the particles having a particle size of 50 µm or more is 20 ppm or less, the effect of suppressing brushing on the surface of the molded body is likely to increase. The preferable content rate is 5 ppm or less.

(D) As a compounding quantity of carbon black, the range of 0.5-5 mass% is preferable in a liquid crystal resin composition. When the blending amount of the carbon black is 0.5% by mass or more, the jet-blackness of the obtained resin composition is less likely to decrease, and anxiety is unlikely to appear in the light-shielding properties. If the blending amount of carbon black is 5% by mass or less, it is not economical, and boots are hardly generated.

[(E) release agent]

The mold release agent (E) used as an optional component in the present invention is not particularly limited as long as it is generally available, and examples thereof include fatty acid esters, fatty acid metal salts, fatty acid amides, and low molecular weight polyolefins. , A fatty acid ester of pentaerythritol (for example, pentaerythritol tetrastearate) is preferred.

(E) As a compounding quantity of a mold release agent, 0.1-3 mass% of range is preferable in a liquid crystal resin composition. When the compounding amount of the mold release agent is 0.1% by mass or more, the mold release property at the time of molding is improved, and it is easy to obtain a molded article with reduced sliding abrasion. If the compounding amount of the mold release agent is 3% by mass or less, MD is likely to be reduced.

[Other ingredients]

In the liquid crystal resin composition of the present invention, to the extent that the effects of the present invention are not impaired, other polymers, other fillers, generally known substances added to synthetic resins, that is, stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents , Flame retardants, colorants such as dyes or pigments, lubricants, crystallization accelerators, crystal nucleating agents, etc. can also be appropriately added according to the required performance.

Other fillers include fillers other than (B) talc and (D) carbon black, and examples thereof include granular fillers such as silica. However, it is preferable that the liquid crystalline resin composition of the present invention does not contain mica from the viewpoints of improving adhesiveness and reducing melt viscosity, MD, and sliding abrasion.

[Preparation Method of Liquid Crystalline Resin Composition for Sliding Wear Members]

The method for preparing the liquid crystal resin composition for sliding wear-resistant members of the present invention is not particularly limited. For example, by mixing the components (A) to (C), and melt-kneading them using a single-screw or twin-screw extruder, preparation of a liquid crystal resin composition for abrasion-resistant wear members is achieved.

[Liquid Crystal Resin Composition for Sliding Wear Members]

It is preferable that the liquid crystalline resin composition of this invention obtained as mentioned above has a melt viscosity of less than 70 Pa*sec from a viewpoint of MD reduction. One of the characteristics of the liquid crystal resin composition of the present invention is that the fluidity at the time of melting is high and the moldability is excellent. The melt viscosity is more preferably 60 Pa·sec or less, and even more preferably 55 Pa·sec or less. The lower limit of the melt viscosity is not particularly limited, and may be, for example, 30 Pa·sec or more, and 40 Pa·sec. In this specification, as the melt viscosity, a value obtained by a measurement method in accordance with ISO 11443 is adopted under conditions of a cylinder temperature 10 to 20°C higher than the melting point of the liquid crystalline resin and a shear rate of 1000 sec ^-1 .

<No sliding wear>

Using the liquid crystal resin composition of the present invention, a sliding wear-resistant member is prepared. The sliding wear-resistant member of the present invention has the same adhesiveness and impact resistance as the conventional one, while reducing the sliding wear resistance. The wear-resistant wear-resistant member of the present invention can be used for a component in which two or more members are dynamically contacted during use, specifically, for example, a connector such as an FPC connector; Sockets such as memory card sockets; Parts for camera modules such as a lens holder; It can be used for relays.

[ Example ]

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

<Liquid Crystal Resin>

액정성 폴리에스테르아미드 수지

Liquid crystalline polyesteramide resin

After adding the following raw materials to the polymerization vessel, the temperature of the reaction system was raised to 140°C and reacted at 140°C for 1 hour. Then, it was further heated to 340°C over 4.5 hours, and depressurized to 10 Torr (i.e., 1330 Pa) over 15 minutes from here, to drain acetic acid, excess acetic anhydride, and other low secretions. Melt polymerization was performed while being discharged. After the stirring torque reached a predetermined value, nitrogen was introduced to pressurize from a depressurized state to a normal pressure, the polymer was discharged from the lower portion of the polymerization vessel, and the strands were pelletized to obtain pellets. The obtained pellets were heat-treated at 300°C for 2 hours under a nitrogen stream to obtain a desired polymer. The melting points of the obtained polymers were 19.0 Pa·s at 336°C and 350°C. The melt viscosity of the polymer was measured in the same manner as the measurement method of melt viscosity described later.

(I) 4-hydroxybenzoic acid (HBA); 1380 g (60 mol%)

(II) 2-hydroxy-6-naphthoic acid (HNA); 157 g (5 mol%)

(III) terephthalic acid (TA); 484 g (17.5 mol%)

(IV) 4,4'-dihydroxybiphenyl (BP); 388 g (12.5 mol%)

(V) 4-acetoxyaminophenol (APAP); 126 g (5 mol%)

Metal catalyst (potassium acetate catalyst); 110mg

Acylating agent (acetic anhydride); 1659 g

<Materials other than liquid crystalline resin>

탤크 1: 크라운 탤크 PP(마츠무라산업(주)제, 탤크, 중앙직경 14.6㎛)

Talc 1: Crown talc PP (manufactured by Matsumura Industries, Talc, central diameter 14.6㎛)

탤크 2: GH50(하야시카세이(주)제, 탤크, 중앙직경 19.5㎛)

Talc 2: GH50 (Hayashi Kasei Co., Ltd., talc, median diameter 19.5 µm)

탤크 3: MS-KY(일본타루크(주)제, 탤크, 중앙직경 22.4㎛)

Talc 3: MS-KY (Japan Taruk Co., Ltd., talc, central diameter 22.4㎛)

마이카: AB-25S((주)야마구찌마이카제, 마이카, 중앙직경 25.0㎛)

Mica: AB-25S (Yamaguchi-Mikaze Co., Ltd., Mica, 25.0㎛ central diameter)

에폭시기 함유 올레핀계 공중합체: 본드패스트 2C(스미토모화학(주)제, 에틸렌-글리시딜메타크릴레이트 공중합체, 글리시딜메타크릴레이트의 함유량 6질량%)

Epoxy group-containing olefin copolymer: Bond Fast 2C (Sumitomo Chemical Co., Ltd., ethylene-glycidyl methacrylate copolymer, glycidyl methacrylate content 6% by mass)

카본블랙: VULCAN XC305(캐봇재팬(주)제, 평균 입자경 20nm, 입자경 50㎛ 이상의 입자 비율이 20ppm 이하)

Carbon black: VULCAN XC305 (manufactured by Cabot Japan Co., Ltd., with an average particle diameter of 20 nm, a particle ratio of 50 µm or more and a particle ratio of 20 ppm or less)

이형제: 펜타에리트리톨 테트라스테아레이트(에머리올레오케미컬즈 재팬(주)제)

Mold release agent: Pentaerythritol tetrastearate (manufactured by Emery Ole Chemicals Japan Co., Ltd.)

<Preparation of liquid crystal resin composition for sliding wear-resistant member>

The components were melt-kneaded at a cylinder temperature of 350° C. using a twin-screw extruder (TEX30α type manufactured by Nippon Steel Co., Ltd.) at a ratio shown in Table 1 or 2 to obtain a liquid crystal resin composition pellet for a sliding wear-resistant member. .

<melt viscosity>

The melt viscosity of the liquid crystal resin compositions of Examples and Comparative Examples was measured using the pellets. Specifically, with a capillary rheometer (Toyo Seiki Co., Ltd., Capillograph 1D: piston diameter 10 mm), the apparent melt viscosity at a cylinder temperature of 350°C and a shear rate of 1000 sec ^-1 was determined by ISO 11443. It measured according to the criteria. For the measurement, an orifice having an inner diameter of 1 mm and a length of 20 mm was used. The results are shown in Tables 1 and 2.

<Bending test>

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine ("SE100DU" manufactured by Sumitomo Heavy Industries, Ltd.) to prepare a flexural test specimen of 130 mm x 13 mm x 0.8 mm. Using this test piece, flexural strength, flexural modulus, and fracture strain were measured according to ASTM D790. Among these, the results of measurement of the flexural modulus are shown in Tables 1 and 2.

〔Molding conditions〕

Cylinder temperature: 350℃

Mold temperature: 90℃

Injection speed: 33mm/sec

Packing pressure: 50MPa

<Epoxy adhesive>

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine ("SE100DU" manufactured by Sumitomo Heavy Industries, Ltd.) to obtain a test piece (ISO Test Piece Type 1A, 4 mm thick). This test piece was divided into two, and as shown in Fig. 1(a), was attached with an epoxy adhesive (Lactite 3128NH, manufactured by Henkel) (curing condition: 80°C×30 min). Thereafter, as shown in Fig. 1(b), an attached test piece was installed, and a tensile tester was used to apply a load in the direction of the arrow, and the adhesive strength was evaluated from the peeled load. The results are shown in Tables 1 and 2.

〔Molding conditions〕

Cylinder temperature: 350℃

Mold temperature: 80℃

Injection speed: 33mm/sec

〔Tensile test conditions〕

Tester: Orientec, Tensiron RTC-1325A

Test speed: 10mm/min

<Charpy impact test>

The pellets of Examples and Comparative Examples were molded into test pieces (4 mm x 10 mm x 80 mm) for measurement under the following molding conditions using a molding machine ("SE100DU" manufactured by Sumitomo Heavy Industries, Ltd.). Using these test pieces, the Charpy impact value was measured by a method based on ISO179-1. The results are shown in Tables 1 and 2.

〔Molding conditions〕

Cylinder temperature: 350℃

Mold temperature: 80℃

Back pressure: 2.0MPa

Injection speed: 33mm/sec

<Evaluation of Mold Deposition (MD)>

While the pellets of Examples and Comparative Examples were used as a raw material, the test piece shown in Fig. 2 was continuously molded (500 times) under the following molding conditions using a molding machine ("ROBOSHOT S2000i30A" manufactured by Fanak Co., Ltd.). Before and after molding, the adhesion area of the white deposits in the cavity was visually observed, and the status of MD reduction was evaluated based on the following criteria.

○ (good): No white deposit was observed.

Δ (normal): A white deposit occurred within a range of 7 mm or less from the vent portion.

× (poor): A white deposit was generated beyond 7 mm from the vent portion.

Here, the vent part refers to a mold-like portion corresponding to the left end of the test piece shown in FIG. 2.

〔Molding conditions〕

Cylinder temperature: 360℃

Mold temperature: 90℃

Injection time: 2sec

Cooling time: 5sec

<Sliding wear amount>

The pellets of Examples and Comparative Examples were molded under the following molding conditions using a molding machine ("SE100DU" manufactured by Sumitomo Heavy Industries, Ltd.), measuring pins (diameter 10 mm, length 10 mm) and test specimens (80 mm) × 80 mm × 1 mm). As shown in Fig. 3, a load is applied to the measuring pin on the measuring test piece, a reciprocating sliding test is performed under the following reciprocating sliding conditions, and the mass reduction amount of the sum of the measuring pin and the measuring test piece is calculated. It was made into sliding wear amount. The results are shown in Tables 1 and 2.

〔Molding conditions〕

Cylinder temperature: 350℃

Mold temperature: 80℃

Injection speed: 33mm/sec

〔Round-trip sliding conditions〕

Sliding speed: 5cm/sec

Stroke: 20mm

Load: 9.8N (in 1kg)

Round trip: 3000

Note) -: Extrusion is not possible due to increase in resin temperature and increase in viscosity

As is evident from the results shown in Tables 1 and 2, it was confirmed that the molded article of the Examples had adhesiveness and impact resistance equivalent to those of the prior art, and reduced sliding abrasion. Particularly, when the talc content is 25 to 45% by mass, the melt viscosity of the obtained composition is less likely to increase, and when molding such a composition, MD is less likely to occur, and at the same time, the adhesion of the obtained molded body is further improved. It was confirmed that it was easy.

Claims (3)

(A) liquid crystal resin,
(B) talc, and
(C) Epoxy group-containing copolymer,
Containing,
The central diameter of the talc (B) is 14 to 23 μm,
The content of the (B) talc is 30 to 40% by mass,
The content of the (C) epoxy group-containing copolymer is 3.0 to 5.0% by mass, a liquid crystal resin composition for a sliding wear-resistant member. According to claim 1,
The composition of the central diameter of the talc (B) is 17 to 21 µm. A sliding wear-resistant member made of the composition according to claim 1 or 2.

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