JP2002173562A - Thermoplastic elastomer composition for multilayer molding and multilayer molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition for multilayer molding having excellent abrasion resistance and scratch resistance and provide a multilayer molded article produced by using the thermoplastic elastomer composition. SOLUTION: The thermoplastic elastomer composition for multilayer molding contains (A) 30-90 wt.% ethylene-α-olefin copolymer rubber, (B) 5-40 wt.% propylene resin, (C) 1-20 wt.% hydrogenated aromatic vinyl compound-conjugated diene compound copolymer rubber having a vinyl content of >=60% and (D) 0.1-10 wt.% (the sum of A to D is 100 wt.%) silicone oil and/or silicone rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic elastomer composition for multilayer molding and a multilayer molded article. More specifically, the present invention provides a thermoplastic elastomer composition for multilayer molding, which maintains satisfactory levels of flexibility and appearance, and has excellent abrasion resistance and scratch resistance, and a multilayer using the thermoplastic elastomer composition. It relates to a molded article.

[0002]

2. Description of the Related Art For example, multilayer molded articles using a thermoplastic elastomer composition are used for automobile interior parts (console boxes, armrests, etc.). And
The thermoplastic elastomer composition used for such an application is required to have excellent wear resistance and scratch resistance, and the required level has recently become higher. In light of the current situation, conventional thermoplastic elastomer compositions have not always been satisfactory.

[0003]

Under such circumstances, the problem to be solved by the present invention is to maintain a satisfactory level of flexibility and appearance, and at the same time, to form a multilayer molding excellent in abrasion resistance and scratch resistance. Another object of the present invention is to provide a thermoplastic elastomer composition and a multilayer molded article using the thermoplastic elastomer composition.

[0004]

That is, one aspect of the present invention comprises the following components (A) to (D):
The content of (A) is 30 to 90% by weight, the content of (B) is 5 to 40% by weight, and the content of (C) is 1 to 2%.
0% by weight, and the content of (D) is 0.1 to 10% by weight.
(However, the total amount of (A) to (D) is 100% by weight.) The present invention relates to a thermoplastic elastomer composition for multilayer molding. (A): Ethylene-α-olefin copolymer rubber (B): Propylene resin (C): Hydrogenated aromatic vinyl compound-conjugated diene compound copolymer rubber having a vinyl content of 60% or more (D): Silicone oil and / or silicone rubber In another aspect of the present invention, the core is an olefin-based resin, and the skin is formed by two-layer molding of the thermoplastic elastomer composition. It relates to a molded body.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The component (A) of the present invention is an ethylene-α-olefin copolymer rubber. Ethylene-α
Examples of the olefin copolymer rubber include an ethylene-α-olefin copolymer rubber (A1) and an ethylene-α-olefin-conjugated diene copolymer rubber (A2). A mixture of (A1) and (A2) may be used. Also,
As (A), an oil-extended ethylene-α-olefin copolymer rubber may be used.

The α-olefin in (A1) includes propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-octene.
Decene is mentioned, and among them, propylene, 1-butene and 1-octene are preferred. The content of the α-olefin is 10 to 50% by weight, preferably 20 to 40% by weight.

The α-olefin in (A2) includes propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-octene.
Decene is mentioned, and among them, propylene, 1-butene and 1-octene are preferred. As the conjugated diene, 1,4-hexadiene, 1,6-octadiene,
2-methyl-1,5-hexadiene, 6-methyl-1,
Linear unconjugated dienes such as 5-heptadiene, 7-methyl-1,6-octadiene; cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-
Cyclic non-conjugated dienes such as vinyl norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropylenyl-2-norbornene; 2 , 3-Diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, 1,3,7-octatriene, 1,4,9-decatriene And among them, 5-ethylidene-2-norbornene or dicyclopentadiene is preferable. The content of the α-olefin is 10 to 50% by weight, preferably 20 to 40% by weight.

The ethylene-α-olefin copolymer rubber has a Mooney viscosity at 100 ° C. (ML _{1 + 4} 100 ° C.) of 5
To 150, more preferably 20 to 10
0. If the Mooney viscosity is too low, the mechanical strength may be significantly reduced, while if the Mooney viscosity is too high, the appearance of the molded article may be impaired.
In addition, when the oil extended rubber is used as (A), the Mooney viscosity of (A) is based on the value including the extended oil.

The component (B) of the present invention is a propylene resin. Melt flow rate of propylene resin (23
0 ° C., 21.18 N) is 0.1 to 150 g / 10 min.
And preferably 1 to 100 g / 10 min.
If the melt flow rate is too small, the moldability is poor and the appearance may be deteriorated. On the other hand, if the melt flow rate is too large, the mechanical properties may be significantly reduced. Homopolypropylene (B
1), propylene-ethylene random copolymer (B2)
And propylene-ethylene block copolymer (B3). Further, a mixture of (B1), (B2) and (B3) may be used.

[0010] (B1) is a homopolymer of propylene, and if it is desired to increase the rigidity, a polymer having high crystallinity is preferable.

(B2) is a copolymer obtained by randomly polymerizing propylene and ethylene. When it is desired to increase the rigidity, it is preferable to reduce the ethylene content or to have high crystallinity. Conversely, when it is desired to lower the rigidity, it is preferable to increase the ethylene content or lower the crystallinity.

(B3) is a block copolymer comprising a first segment and a second segment, wherein the first segment is a homopropylene portion of propylene homopolymerization and the second segment is a propylene-ethylene random copolymer portion. is there. As the first segment, a propylene-ethylene random copolymer having a different ethylene content from the second segment may be used. Further, the content of the propylene-ethylene random copolymer part as the second segment is 30.
You may use the reactor olefin-type thermoplastic elastomer (R-TPO) which is more than weight%. When it is desired to increase the rigidity, those having a small content of the propylene-ethylene random copolymer portion as the second segment and those having a high ethylene content in the propylene-ethylene random copolymer portion are preferable.

The component (C) of the present invention has a vinyl content of 6
A hydrogenated aromatic vinyl compound-conjugated diene compound copolymer rubber of 0% or more.

(C) is a (I)-(II) block copolymer, (I)-(II)-(III) block copolymer,
(I)-(II)-(I) block copolymer [provided that
(I) is an aromatic vinyl compound polymer block, (II) is a conjugated diene polymer block or an aromatic vinyl compound-conjugated diene random copolymer block, and (III) is an aromatic vinyl compound in which the aromatic vinyl compound is gradually increased. -Conjugated diene taper block].

Styrene as an aromatic vinyl compound, α-
Methyl styrene, P-methyl styrene, vinyl xylene, vinyl naphthalene and the like can be mentioned, and styrene is preferred. Examples of the conjugated diene compound include butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 2-neopentyl-1,3-butadiene, with butadiene or isoprene being preferred. Butadiene is particularly preferred when low-temperature impact performance is required as a multilayer molded article. The vinyl content of the conjugated diene portion is the ratio of the amount of 1,2 bonds and / or 3,4 bonds in the polymerized portion of the conjugated diene, and the vinyl content in (II) is 60% or more.
If the amount is too small, the scratch-resistant performance deteriorates.

The component (D) of the present invention is a silicone oil and / or silicone rubber. Silicone oil,
Straight silicone (D1) as silicone rubber,
Modified silicone (D2) can be mentioned.

(D1) includes dimethyl silicone, methyl phenyl silicone and methyl hydrogen silicone.

(D2) is an amino-modified silicone,
Epoxy-modified silicone, carboxyl-modified silicone, carbinol-modified silicone, methacryl-modified silicone, mercaptop-modified silicone, phenol-modified silicone, polyether-modified silicone, methylstyryl-modified silicone, alkyl-modified silicone, higher fatty acid ester-modified silicone, higher alkoxy-modified silicone, There is a fluorine-modified silicone.

The olefin resin may be filled with silicone oil or silicone rubber at a high concentration.

The present invention comprises the above components (A) to (D), wherein the content of (A) is 30 to 90% by weight,
The content of (B) is 5 to 40% by weight, the content of (C) is 1 to 20% by weight, and the content of (D) is 0.1 to 40% by weight.
It is 10% by weight. However, the total amount of (A) to (D) is 100% by weight. And, preferably,
The content of (A) is 50 to 80% by weight, the content of (B) is 10 to 30% by weight, and the content of (C) is 5 to 80% by weight.
10% by weight, and the content of (D) is 2 to 7% by weight. If the content of (A) is too small, flexibility is lost, while if the content of (A) is too large, moldability is poor and appearance is poor.
If the content of (B) is too small, the moldability is poor and the appearance is poor, while if the content of (B) is too large, the composition becomes hard. If the content of (C) is too small, the scratch resistance becomes poor, while if the content of (C) is too large, the wear resistance becomes poor. If the content of (D) is too small, the abrasion resistance will be poor. In addition, about each component, two or more types may be used together, but in that case, the total amount is used as a reference.

The thermoplastic elastomer composition of the present invention may be subjected to dynamic heat treatment using an organic peroxide or a crosslinking aid having two or more double bonds in the molecular structure with the organic peroxide. .

As the organic peroxide, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane, 2,5
-Dimethyl-2,5-di (t-butylperoxy) hexine, 1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-di (t-butylperoxy3,
5,5-trimethylcyclohexane), 2,5-dimethyl-2,5-di (peroxybenzoyl) hexyne, dicumyl peroxide and the like can be used.

As a crosslinking aid, N, N'-m-phenylenebismaleimide, toluylenebismaleimide, p-quinonedioxime, nitrosobenzene, diphenylguanidine, trimethylolpropane, divinylbenzene and the like can be used.

The thermoplastic elastomer composition of the present invention comprises:
In addition to the essential components (A) to (D), inorganic fillers (talc, calcium carbonate, calcined kaolin, etc.), organic fillers (fiber, wood powder, cellulose powder, etc.), lubricants (fatty acid amides, etc.), oxidation Inhibitors (phenol-based, sulfur-based, phosphorus-based, lactone-based, vitamin-based, etc.), weather stabilizers, ultraviolet absorbers (benzotriazole-based, triazine-based, anilide-based, benzophenone-based, etc.), heat stabilizers, light stabilizers (Hindered amines, benzoates, etc.), pigments and the like. In order to further improve the wear resistance, it is preferable to contain an inorganic filler. Further, it is more preferable to contain an inorganic filler and a lubricant. Calcium carbonate is preferred for flexible thermoplastic elastomer compositions.

In order to obtain the thermoplastic elastomer composition of the present invention, for example, melt kneading may be carried out using a twin screw extruder, a Banbury mixer or the like.

The thermoplastic elastomer composition of the present invention comprises:
Used for multilayer molding. Preferable specific examples of the multilayer molded article include a molded article formed by two-layer molding in which the core portion is an olefin-based resin and the skin portion is made of the thermoplastic elastomer composition of the present invention. When a soft feeling is required for the skin portion, the hardness (shoreA) of the thermoplastic elastomer composition is preferably 99 or less. More preferably, the hardness (shoreA) is 90-60.

Examples of the olefin resin in the core include propylene resins, ethylene resins, olefin thermoplastic elastomers and the like.

In order to obtain a molded article formed by the above-described two-layer molding, for example, coextrusion by an extruder, two-color molding by injection molding, insert molding, and the like may be performed.

Preferred examples of the molded article of the present invention include:
Automotive interior parts, such as instrument panels, doors, armrests, grab rails,
Shift knob, instrument panel grip, side brake knob,
Console boxes, glass runs, weather strips and the like can be mentioned.

[0030]

The following examples illustrate the invention in more detail. [I] Raw material (A) Ethylene-α-olefin copolymer A-1; oil-extended ethylene-propylene-conjugated diene copolymer rubber having Mooney viscosity (ML _{1 + 4} 100 ° C) = 90 [conjugated diene; ENB oil extension 70 parts] (EPDM) A-2: Oil-extended ethylene-propylene-conjugated diene copolymer rubber having Mooney viscosity (ML _{1 + 4} 100 ° C) = 53 [conjugated diene; ENB oil extension 100 parts (EPDM) (B) Propylene resin B-1; MFR (230 ° C., 21.18 N) = 30 g /
10 min propylene-ethylene block copolymer (BLOCK-PP) B-2; MFR (230 ° C., 21.18 N) = 0.5 g
/ 10 min polypropylene (HOMO-PP) (C) Aromatic vinyl compound-conjugated diene compound copolymer C-1; Dynalon 1321P (H-SBR) (D) silicone manufactured by JSR Corporation D-1; Dow Corning Toray -BY27-001 manufactured by Silicone Co., Ltd. (E) Inorganic filler E-1; NS100 (calcium carbonate) manufactured by Nitto Powder Chemical Co., Ltd.

[II] Measuring Method The obtained composition was prepared at a cylinder temperature of 220.degree. C. and a mold temperature of 50.degree.
After forming a flat plate with a grain of 0 mm × 90 mm, necessary measurements were made. (1) Scratch resistance test: Using a surface property measuring device Tribogear (manufactured by Shinto Kagaku) to scratch the grained surface of a plate with grain by injection at a constant speed with a scratching needle loaded with a load of 300 g. And the scratch was evaluated by visual observation. ；: Good (scratch is not conspicuous) ×: bad (scratch is conspicuous) (2) Abrasion test: cloth (Kanakin 3)
No.), a plate with a grain was attached, a load of 500 g was applied, and the abraded surface obtained by rubbing the grain surface 200 times with a cloth was evaluated by visual observation. ；: Good (the grain is hardly worn or scratches are not conspicuous) ×; poor (the grain is worn or scratches are noticeable)

Example 1 and Comparative Example 2 The blend of Table 1 and trimethylolpropane trimethacrylate, which is a crosslinking aid, in an amount of 0.1 part by weight are melt-kneaded with a Banbury mixer and then processed into pellets. The pellets and the organic peroxide 2,5-dimethyl-2,5-
0.12 parts by weight of di (t-butylperoxy) hexane was dynamically heat-treated with a twin-screw extruder. The obtained composition was molded and measured. The results are shown in Table 1.

Example 2 0.1 parts by weight of the compound shown in Table 1 and trimethylolpropane trimethacrylate, which is a crosslinking aid, are melt-kneaded with a Banbury mixer and then processed into pellets. The pellets and the organic peroxide 2,5-dimethyl-2,5-
0.12 parts by weight of di (t-butylperoxy) hexane is dynamically heat-treated with a twin-screw extruder, and further, 20 parts by weight of a composition heat-treated with a twin-screw extruder and 20 parts by weight of calcium carbonate as an inorganic filler are kneaded. Was done. Molding the resulting composition,
A measurement was made. The results are shown in Table 1.

Comparative Example 1 0.8 parts by weight of the composition shown in Table 1 and N, N'-m-phenylenebismaleimide as a crosslinking aid were melt-kneaded with a Banbury mixer, and then processed into pellets. 0.32 parts by weight of the pellet and 2,5-dimethyl-2,5-di (t-butylperoxy) hexane as an organic peroxide were dynamically heat-treated by a twin-screw extruder. The obtained composition was molded and measured. The results are shown in Table 1.

[0035]

[Table 1]

[0036]

As described above, according to the present invention, it is possible to provide a thermoplastic elastomer composition for multilayer molding excellent in abrasion resistance and scratch resistance, and a multilayer molded article using the thermoplastic elastomer composition. did it.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 83/04 C08L 83/04 (72) Inventor Eiji Nakaishi 5-1, Anesaki Beach, Ichihara City, Chiba Prefecture Sumitomo Chemical F-term (reference) 4F071 AA12X AA15 AA15X AA20 AA20X AA21X AA22X AA67 AA75 BA01 BB05 BC07 4F100 AK03B AK07A AK11A AK28A AK52A AK62A AL01A AL09A AN02A BB12 BB12 BB12 BB12 EB12 BB12 BB12 BB12 BB12 GF00

Claims (3)

[Claims] 1. It contains the following components (A) to (D),
The content of (A) is 30 to 90% by weight, the content of (B) is 5 to 40% by weight, and the content of (C) is 1 to 2%.
0% by weight, and the content of (D) is 0.1 to 10% by weight.
(However, the total amount of (A) to (D) is 100% by weight.) A thermoplastic elastomer composition for multilayer molding. (A): Ethylene-α-olefin copolymer rubber (B): Propylene resin (C): Hydrogenated aromatic vinyl compound-conjugated diene compound copolymer rubber having a vinyl content of 60% or more (D): silicone oil and / or silicone rubber 2. A molded article formed by two-layer molding comprising a core part comprising an olefin-based resin and a skin part comprising the thermoplastic elastomer composition according to claim 1. 3. A molded article according to claim 2, which is an automobile interior part.