JPH10330610A - Slidable sheet article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a thin sheet having excellent heat resistance, sliding resistance and impact resistance and a slidable article, comprising a specific polyphenylene ether-based resin, a polyolefin and a prescribed copolymer. SOLUTION: This slidable sheet article is obtained by extrusion molding a resin composition comprising (A) 50-85 wt.% of a polyphenylene ether based resin which is composed of a mixture of a polyphenylene ether which is a (co)polymer constituted of a repeating unit of formula I and/or formula II (R1 to R6 are each a 1-4C alkyl, an aryl, a halogen or H with the proviso that R5 and R6 are not H at the same time) and optionally a styrene resin, (B) 3-20 wt.% of a polyolefin having 130,000 number-average molecular weight and (C) 5-30 wt.% of a hydrogenated block copolymer of a vinyl aromatic compound and a conjugated diene, having 20-40% of bonded amount of the vinyl aromatic compound and >=150,000 weight-average molecular weight to give a thin sheet and optionally processing the sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin sheet excellent in heat resistance, slidability and impact resistance, which is generally referred to as fish-eye and buttocks, has little gel-like foreign matter, and is excellent in slidability. And a slidable article obtained by processing the same.

[0002]

2. Description of the Related Art Polyphenylene ether has excellent mechanical properties, electrical properties, heat resistance, low water absorption and excellent dimensional stability. For example, polyphenylene ether is used for industrial parts, electric / electronic parts, office equipment, housing, automobile parts, etc. It has been put to practical use in various applications such as precision parts. However, these commercially available polyphenylene ether-based plastics have poor self-lubricating properties, which are disadvantages of non-crystalline resins, and have a high dynamic friction coefficient, so they are melted by frictional heat and contact / rotation of bearings, gears, etc. Has the disadvantage that it cannot be used as a sliding member having the above-mentioned portion. For this reason, for example, Japanese Patent Application Laid-Open
In Japanese Patent No. 22040, although a proposal has been made to improve the slidability by adding mineral oil or the like to polyphenylene ether, silver marks are formed on the surface of the molded product, which is not practical. JP-A-61-185560 discloses that a composition containing potassium titanate whisker and powdered high-density polyethylene in a polyphenylene ether-based resin gives a resin composition for a sliding member having excellent wear resistance. Although there is a proposal, a molded article of the composition obtained here not only causes extreme delamination, but also deforms (dents) the friction surface after the continuous friction running test.

Further, JP-A-62-141062 proposes a resin composition comprising a polyphenylene ether-based resin and an alkyldiphenyl ether, which exhibits a decrease in kinetic friction coefficient and an improvement in the limit PV value. In addition, there is a decrease in heat resistance, a melting phenomenon occurs during a continuous wear running test, and the amount of friction and wear increases, which is not practical. Further, JP-A-4-7357 and JP-A-4-24-2
No. 79697 discloses a polyphenylene ether, a polyolefin having a low dynamic friction coefficient, a block copolymer of a vinyl aromatic compound having a Young's modulus of 1500 kg / cm ² or more as a compatibilizer and a conjugated diene compound or a hydrogenated product thereof. A resin sliding member having excellent delamination, weld strength, and abrasion / abrasion resistance by controlling the dispersion mode is disclosed. However,
In these inventions, although an excellent sliding effect is exhibited, it is not sufficient for a demand for high durability having higher impact strength. In addition, especially when the thickness is 1 mm
The extrudability of the following thin sheets is not satisfactory,
A thin sheet excellent in heat resistance and durability could not be obtained. Furthermore, there was no knowledge for obtaining a highly durable thin sheet having excellent heat resistance, impact resistance and sliding properties.

[0004]

An object of the present invention is to provide a polyphenylene ether-based resin composition having excellent heat resistance, sliding resistance and impact resistance.
An object of the present invention is to provide a highly durable thin sheet having little gel-like foreign matter and excellent in slidability, and a slidable article obtained by processing the same.

[0005]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that a hydrogenated block copolymer of a polyphenylene ether, a polyolefin, and a specific vinyl aromatic compound and a conjugated diene compound is basically used. As a component, a resin composition in which each component has a specific ratio is excellent in thin sheet extrudability, and it has been found that the obtained thin sheet and a molded article obtained by processing the same achieve the above-mentioned objects, and have reached the present invention. Was.

That is, the present invention relates to (a) 50-85% by weight of a polyphenylene ether or a mixture of polyphenylene ether and a styrene resin, (b) 3-20% by weight of a polyolefin, and (c) an amount of bound styrene of 2%.
0 to 40% by weight, and a hydrogenated block copolymer (HA) of a vinyl aromatic compound having a weight average molecular weight of 150,000 or more and a conjugated diene compound is 5 to 30% by weight, preferably,
Further, (d) the binding amount of the vinyl aromatic compound is 40% by weight.
A thin sheet excellent in slidability, comprising a resin composition containing 3 to 20% by weight of a hydrogenated block copolymer (HB) of a vinyl aromatic compound and a conjugated diene compound, and a sheet obtained by processing the sheet The resulting slidable article.

Hereinafter, the present invention will be described in detail. The (a) polyphenylene ether used in the present invention is represented by the following general formula (1) and / or general formula (2):

[0008]

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[0009]

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Wherein R1, R2, R3, R4, R5,
R6 independently represents an alkyl group having 1 to 4 carbon atoms, an aryl group, halogen, or hydrogen. However, a homopolymer or a copolymer having (R5 and R6 not simultaneously hydrogen) as a repeating unit can be used. Representative examples of the homopolymer of polyphenylene ether include poly (2,6-dimethyl-1,1).
4-phenylene) ether, poly (2-methyl-6-ethyl1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2-ethyl-6-n-propyl) -1,4-phenylene) ether, poly (2,6-di-n-propyl-1,4-phenylene) ether, poly (2-methyl-6-n-butyl-
1,4-phenylene) ether, poly (2-ethyl-6)
-Isopropyl-1,4-phenylene) ether, poly (2-methyl-6-chloroethyl-1,4-phenylene) ether, poly (2-methyl-6-hydroxyethyl-1,4-phenylene) ether, poly ( Homopolymers such as 2-methyl-6-chloroethyl-1,4-phenylene) ether are exemplified.

The polyphenylene ether copolymer is 2,2
Copolymer of 6-dimethylphenol and 2,3,6-trimethylphenol or copolymer of o-cresol or 2,3,6-trimethylphenol and o-cresol
Includes polyphenylene ether copolymers having a polyphenylene ether structure as a main component, such as copolymers with cresol.

Further, the polyphenylene ether of the present invention contains, as a partial structure, various other phenylene ether units which have conventionally been proposed to be allowed to exist in the polyphenylene ether without departing from the gist of the present invention. You can go out. Examples of those proposed to coexist in a small amount include 2- (dialkylaminomethyl) -6-methylphenylene ether described in Japanese Patent Application Nos. 63-12698 and 63-301222. Unit or 2- (N-alkyl-N-
Phenylaminomethyl) -6-methylphenylene ether unit. Also included are polyphenylene ethers in which a small amount of diphenoquinone or the like is bonded in the main chain. Further, for example, JP-A-2-276823, JP-A-63-108059, and JP-A-59-5
Also included is a polyphenylene ether modified with a compound having a carbon-carbon double bond described in, for example, JP-A-9724.

The polyphenylene ether used in the present invention preferably has an intrinsic viscosity of 0.35 to 0.60 as measured in a chloroform solution at 30 ° C.,
A value of 0.55 is more preferable. In the present invention, a part of the polyphenylene ether can be replaced with a styrene-based resin as long as heat resistance and other properties are not impaired.

In the present invention, the styrene resin used as a mixture with polyphenylene ether as the other component constituting (a) is a styrene compound, a compound copolymerizable with the styrene compound, or a rubbery polymer. It is a polymer obtained by polymerization in the absence. Specific examples of the styrene compound include styrene, α-methylstyrene, 2,4
-Dimethylstyrene, monochlorostyrene, p-methylstyrene, p-tert-butylstyrene, ethylstyrene and the like. Examples of the compound copolymerizable with the styrene compound include methacrylic acid esters such as methyl methacrylate and ethyl methacrylate; unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile; and acid anhydrides such as maleic anhydride. And used together with styrenic compounds. The amount of the copolymerizable compound used is 20 to the total amount with the styrene compound.
% By weight or less, more preferably 15% by weight or less.

Examples of the rubbery polymer include a conjugated diene rubber, a copolymer of a conjugated diene and an aromatic vinyl compound, and an ethylene-propylene copolymer rubber. Specifically, polybutadiene and a styrene-butadiene copolymer are particularly preferred. When an unsaturated rubbery polymer is used, it is preferable to use a partially hydrogenated partially hydrogenated rubbery polymer.

Particularly preferred as the styrene resin are polystyrene and rubber-modified polystyrene.
The method for producing the styrenic resin of the present invention is not limited, and any of bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization well known to those skilled in the art may be used. The polyolefin (b) used in the present invention is a polyolefin having a number average molecular weight of 30,000 or more, which is used as a usual molding material. Examples thereof include high-density polyethylene, low-density polyethylene, ultra-high-molecular-weight high-density polyethylene, and low-density polyethylene. , Linear low density polyethylene, density 0.9
A copolymer of two or more compounds selected from ultra-low density polyethylene having less than 0, isotactic polypropylene, ethylene, propylene, other α-olefins, unsaturated carboxylic acids or derivatives thereof, for example, ethylene / butene -1 copolymer, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer, propylene / ethylene (random, block) copolymer, propylene / 1-hexene copolymer, Propylene / 4-methyl-1-pentene copolymer and poly (4
-Methyl-1-pentene), polybutene-1 and the like, and these can be used alone or in combination of two or more. Of these polyolefins, polyethylene is preferred, and low density polyethylene, linear low density polyethylene, and high density polyethylene are preferred.

The hydrogenated block copolymers (c) and (d) used in the present invention are obtained by hydrogenating a block copolymer comprising a vinyl aromatic compound and a conjugated diene compound. At least 80%, preferably 95%, of the olefinic double bonds based on the compound
The above is the result of hydrogenation. And this hydrogenation rate can usually be known by an infrared spectrophotometer, NMR or the like. Specific examples of the bond between the polymer block (A) of the vinyl aromatic compound and the polymer block (B) of the conjugated diene compound include AB, ABA, ABAB, (A −
B) ₄ · Si and the like.

Examples of the vinyl aromatic compound constituting the block copolymer of a vinyl aromatic compound and a conjugated diene compound include styrene, α-methylstyrene, vinyltoluene, p-tert-butylstyrene, diphenylethylene and the like. One or more kinds can be selected from the above, and among them, styrene is preferable. Further, as the conjugated diene compound,
For example, one or more kinds are selected from butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene and the like, and among them, butadiene, isoprene and a combination thereof are preferable.

The (c) hydrogenated block copolymer (HA) of a vinyl aromatic compound and a conjugated diene compound used in the present invention has a bound styrene content of 20 to 40% by weight, preferably 30 to 40% by weight. And the weight average molecular weight is 150,000 or more, preferably 200,000 or more. Further, (d) the hydrogenated block copolymer (HB) of the vinyl aromatic compound and the conjugated diene compound used in the present invention has a vinyl aromatic compound binding amount of 40% by weight or more, preferably 50 to 90% by weight. And having a weight average molecular weight of 50,000 or more.

These hydrogenated block copolymers may be those obtained by any production method as long as they have the above-mentioned structure. Examples of known production methods include, for example, JP-A-47-11486, JP-A-49-66743, and JP-A-50-7.
No. 5651, JP-A-54-126255, JP-A-56-10542, JP-A-56-62847
JP-A-56-100840, British Patent No. 1130770, and US Pat. Nos. 3,281,383 and 3,693,517; There is a method described in.

As the hydrogenated block copolymer, for example, trade names “Toughtec”, “Clayton G”, “Septon” and the like are commercially available. The mixing ratio of each component of the resin composition that basically constitutes the thin sheet of the present invention and the article obtained by processing the sheet is as follows: (a) polyphenylene ether or a mixture of polyphenylene ether and styrene resin is 50%; ~ 85% by weight, preferably 60-8%
0% by weight, (b) 3-20% by weight of polyolefin, preferably 5-15% by weight, (c) 5-30% by weight of hydrogenated block copolymer (HA), preferably 10-25% by weight. And (d) 3 to 20% by weight when using a hydrogenated block copolymer (HB).

As for the extrusion molding method, as long as the above-mentioned raw materials are used, extrusion molding using a T-die which is usually used for molding a thermoplastic resin film or sheet is possible. Extrusion molding conditions are appropriately selected depending on the heat resistance and melt viscosity of the constituent resin composition, but the usual extrusion temperature and die temperature are in the range of 250 to 350 ° C.
Regarding the structure of the T-die, a straight manifold or a coat hanger type manifold is used, and a coat hanger type is preferably used in order to improve the thickness accuracy of the film or sheet. In addition, the casting roll may be a general roll, but a belt type in which a plurality of rolls are connected by a belt is preferable, and is excellent in quality such as shapeability and uneven thickness of a thermoformed product thereafter. ing.

The thin sheet obtained by extrusion molding can be cut into a desired size and used as it is.
Further, the sheet can be formed into a desired shape by thermoforming such as pressure forming or vacuum forming, and can be used for various sheets and films requiring high heat resistance and high durability, and various heat resistant tray applications. In the present invention, plasticizers, stabilizers, and the like are used as long as the properties of the sheet and the molded article (heat resistance, rigidity, excellent impact resistance, balance of slidability, occurrence of bumps on the film / sheet) are not impaired. An ultraviolet absorber, a flame retardant, a coloring agent, a release agent, a fibrous reinforcing agent such as glass fiber and carbon fiber, and a filler such as glass beads, calcium carbonate, and talc can be added. As the stabilizer, phosphites, hindered phenols, alkanolamines, acid amides, dithiocarbamic acid metal salts, inorganic sulfides, and metal oxides can be used alone or in combination. . In addition, lubricants such as waxes and metal release agents such as ultrahigh molecular weight polymers, which have been conventionally used as processing aids for resins, are effective for improving sheet extrudability and suppressing poor sheet appearance. As other compounding agents, especially compounding of conductive carbon black is useful for IC member applications.

The method for obtaining the resin composition constituting the thin sheet of the present invention includes, for example, a heat-melt kneading method using a single-screw extruder, a twin-screw extruder, a roll, a kneader, a Banbury mixer or the like. The melt kneading method using a twin screw extruder is most preferred. The melt-kneading temperature at this time is not particularly limited, but is usually 250 to 3
Arbitrarily select in the range of 50 ° C.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to the following examples. The properties of the materials in the examples were evaluated by the following methods. Here, since the heat deformation temperature and the Izod impact strength cannot be measured with a thin sheet, they were measured using an injection molded product. 1) Heat deformation temperature According to ASTM D-648, load 18.6kg / c
It was measured in m ² . 2) Izod impact strength Measured according to ASTM D-256. 3) Sheet Extrudability / Sheet Appearance Using a single-screw sheet extruder with a screw diameter of 40 mmφ and a T-die with a lip gap of 1.2 mm and a width of 500 mm, the cylinder temperature of the extruder is 300 ° C. and the die temperature is 30.
At 0 ° C., a sheet having a thickness of 0.15 mm was extruded.
At that time, the sheet extrudability, such as ease of adjusting the thickness of the sheet and ease of taking-off, and the surface appearance of the picked-up sheet (the generation of fish eyes and spots) were visually determined. As a result, good samples were indicated by “、”, poor samples were indicated by “×”, and those judged to be at an intermediate level were indicated by “△”. 4) Slidability test A pin made of polyethylene terephthalate resin (injection) having a cylindrical shape with a diameter of 5 mm and a length of 15 mm, and a semicylindrical flat surface with a radius of 1.25 mm and a horizontal length of 4.5 mm attached to the tip. Molded article) is attached so that the semi-cylindrical column is in contact with the extruded sheet, and is attached on a movable plate, and has a thickness of 0.15 mm.
, And apply a load of 500 g to the top of the pin. Thereafter, a friction / wear promotion test of a pin / plate method in which the movable plate was reciprocated 20 mm at a speed of 30 mm / sec was performed, and a friction coefficient at 10,000 reciprocations was measured. The smaller the coefficient of friction, the better the slidability. As a result, good samples were indicated by “、”, poor samples were indicated by “×”, and those judged to be at an intermediate level were indicated by “△”. 5) Delamination test Using an injection molding machine with a mold clamping pressure of 80 tons, cylinder temperature 3
ASTM D-638 at 10 ° C and mold temperature of 120 ° C
A tensile test piece was molded in accordance with the above-mentioned method, and the presence or absence of laminar peeling when repeatedly bent was visually determined.

The components used in the examples are as follows. PPE-1: poly (2,6-dimethyl-1,4-phenylene) ether having an intrinsic viscosity of 0.46 (dl / g) measured with a chloroform solution at 30 ° C. PPE-2: chloroform solution at 30 ° C. Poly (2,6-dimethyl-1,4-phenylene) ether PS-1 having an intrinsic viscosity of 0.38 (dl / g) measured by the above: Homopolystyrene 6 manufactured by Asahi Kasei Corporation
85 PS-2: High impact polystyrene with a rubber content of 12% by weight PE-1: Asahi Kasei Kogyo Co., Ltd., low density polyethylene Suntech LD-M1804 EP-1: Mitsui Petrochemical Co., Ltd., ethylene-propylene copolymer , Tuffmer P-0680 SEB-1: a hydrogenated product of an ABA type styrene-butadiene block copolymer. (Weight average molecular weight 240,
000, styrene block content 30% by weight, hydrogenation rate of polybutadiene part 99.9%) SEB-2: hydrogenated product of styrene-butadiene block copolymer of ABAB type. (Weight average molecular weight 9
SEB-3: a hydrogenated product of an ABAB type styrene-butadiene block copolymer. 000, styrene block content 60% by weight, hydrogenation rate of polybutadiene part 99.9%. (Weight average molecular weight 8
000, styrene block content 30% by weight, hydrogenation rate of polybutadiene part 99.9%) SB-1: unhydrogenated (AB) ₄ -Si type styrene-butadiene block copolymer. (Weight average molecular weight 140,000, styrene block content 30% by weight)

[0027]

Examples 1 to 6 and Comparative Examples 1 to 3 Each of the compositions shown in Table 1 was prepared by using a screw having a screw diameter of 2 at a cylinder temperature of 320 ° C.
Melt and kneaded at 250 rpm with a 5 mm twin screw extruder,
A composition pellet was obtained. Next, the composition pellets are
Using an injection molding machine with a mold clamping pressure of 80 tons, cylinder temperature 3
A test piece was molded at 10 ° C. and a mold temperature of 120 ° C., and the heat deformation temperature and Izod impact strength were measured.

Further, the composition pellets were obtained by using a uniaxial sheet extruder having a screw diameter of 40 mmφ and a T die having a width of 500 mm and a lip gap adjusted to 1.2 mm.
Extruder cylinder temperature 300 ° C, die temperature 300 ° C,
At a roll temperature of about 100 ° C., a sheet having a thickness of 0.15 mm was extruded. Table 1 shows the evaluation results.

[0029]

[Table 1]

[0030]

The thin sheet comprising the specific polyphenylene ether-based resin composition of the present invention and the slidable article obtained by processing the same have excellent sliding properties, heat resistance and impact resistance. Also, it has excellent surface appearance and is useful as various sliding members having repeated dynamic contact.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI // (C08L 71/12 25:00 53:02 23:02)

Claims (4)

[Claims] 1. (a) 50-85% by weight of a polyphenylene ether-based resin comprising a polyphenylene ether or a mixture of a polyphenylene ether and a styrene-based resin;
(B) Hydrogenation of a vinyl aromatic compound having 3 to 20% by weight of a polyolefin, (c) a binding amount of a vinyl aromatic compound of 20 to 40% by weight, and a weight average molecular weight of 150,000 or more and a conjugated diene compound. When the block copolymer (HA) is 5
A thin sheet comprising a resin composition of 30% by weight and having excellent slidability, and a slidable article obtained by processing the sheet. (D) the amount of the vinyl aromatic compound bonded is 4
0% by weight or more of a hydrogenated block copolymer (HB) of a vinyl aromatic compound and a conjugated diene compound,
A thin sheet excellent in slidability and a slidable article obtained by processing the sheet, comprising the resin composition according to claim 1 containing 20% by weight. 3. The hydrogenated block copolymer (HA) has a weight average molecular weight of 200,000 or more, and the hydrogenated block copolymer (HB) has a vinyl aromatic compound binding amount of 50% by weight.
The thin sheet excellent in slidability according to claim 1 or 2, comprising a resin composition characterized by the above, and a slidable article obtained by processing the sheet. 4. The method according to claim 1, wherein the thickness is 1 mm or less.
A thin sheet excellent in the slidability described above and a slidable article obtained by processing the sheet.