JP2002285004A - Thermoplastic elastomer composition and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition having excellent marring resistance and a production method thereof. SOLUTION: The thermoplastic elastomer composition contains a resin component and two or more rubber components, wherein at least one rubber component forms a continuous phase and/or network-like phase, and at least another rubber component forms an isolation phase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a thermoplastic elastomer composition and a method for producing the same. More specifically, the present invention relates to a thermoplastic elastomer composition having excellent scratch resistance and a method for producing the same.

[0002]

2. Description of the Related Art Hitherto, since a molded article molded using a thermoplastic elastomer is used after being painted, scratch resistance is imparted by a coating film, and therefore, a thermoplastic elastomer has not been required. In recent years, the number of molded articles to be coated has decreased, and the scratch resistance has been emphasized, and the required performance has been further enhanced. In light of the current situation, conventional methods for producing thermoplastic elastomers have not always been satisfactory.

[0003]

Under these circumstances, an object of the present invention is to provide a thermoplastic elastomer composition having excellent scratch resistance and a method for producing the same.

[0004]

That is, the first invention of the present invention comprises a resin component and two or more rubber components, and at least one rubber component forms a continuous phase and / or a network-like phase. None, the present invention relates to a thermoplastic elastomer composition in which at least one other rubber component forms an isolated phase. In another aspect of the present invention, a rubber component that forms an isolated phase with a resin component is charged into a kneader, melt-kneaded or dynamically heat-treated, and then forms a continuous phase and / or a network-like phase. The present invention relates to a method for producing the above thermoplastic elastomer composition in which a rubber component is charged.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin component of the present invention is a thermoplastic resin which melts and plasticizes when heated. Examples of the thermoplastic resin include an olefin resin, a styrene resin, a vinyl chloride resin, an acrylic resin, and a carbonate resin, and an olefin resin and a styrene resin are preferable. Further, a mixture of an olefin resin and a styrene resin may be used. Styrene resins include polystyrene and high impact polystyrene. Examples of the olefin-based resin include an ethylene-based resin, a propylene-based resin, and a butene-based resin, and may be a single substance or a mixture. As the olefin resin, an ethylene resin and a propylene resin are preferable.
Examples of the ethylene-based resin include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, and an ethylene copolymer. Examples of the ethylene copolymer include an ethylene-vinyl acetate copolymer and an ethylene-methyl methacryl copolymer. And ethylene-α-olefin copolymers. Examples of the propylene-based resin include polypropylene and a copolymer of propylene, and examples of the propylene copolymer include a propylene-α-olefin copolymer and polypropylene grafted with styrene or a functional group. Α- of propylene-α-olefin copolymer
The olefin is preferably ethylene, and the propylene-ethylene copolymer includes a random copolymer and a block copolymer.

[0006] The propylene-ethylene random copolymer is a copolymer of propylene and ethylene randomly polymerized. If it is desired to increase the rigidity, it is preferable that the propylene-ethylene random copolymer has a low ethylene content and a high crystallinity. Conversely, when it is desired to lower the rigidity, a material having a high crystallinity and a low crystallinity is preferable.

The propylene-ethylene block copolymer comprises 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. It is a copolymer. As the first segment, a propylene-ethylene random copolymer having a different ethylene content from the second segment may be used. 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 small ethylene content of the propylene-ethylene random copolymer portion are preferable. Conversely, when it is desired to lower the rigidity, those having a high 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 rubber component of the present invention is an elastic body which is elastic at room temperature and in a natural state. Examples of the elastic body include solid rubber and thermoplastic elastomer. As solid rubber, isoprene rubber, butadiene rubber, chloroprene rubber,
Examples include nitrile rubber, olefin rubber, epichlorohydrin rubber, polysulfide rubber, silicone rubber, fluorine rubber, urethane rubber, and the like, with isoprene rubber, butadiene rubber, and olefin rubber being preferred. Isoprene-based rubber includes natural rubber, isoprene rubber, and the like, butadiene-based rubber includes butadiene rubber, styrene-butadiene rubber, and 1,2-polybutadiene, and olefin-based rubber includes butyl rubber, acrylic rubber, and acrylic rubber.
There are ethylene-α-olefin-based copolymer rubber, ethylene and / or α-olefin aromatic vinyl compound-based copolymer rubber, and the like. As the ethylene-α-olefin copolymer rubber, ethylene-α-olefin copolymer rubber,
Ethylene-α-olefin conjugated diene copolymer rubber can be mentioned.

The α-olefin in the ethylene-α-olefin copolymer rubber includes propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene and 1-decene. Propylene, 1-butene, 1-hexene and 1-
Octene is preferred. The content of α-olefin is 10 to
It is 50% by weight, preferably 20 to 40% by weight.

As the α-olefin in the ethylene-α-olefin conjugated diene copolymer rubber, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene And the like, among which propylene, 1-butene, 1-hexene and 1-octene are preferred. Examples of the conjugated diene include 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, and 6-methyl-diene.
Linear unconjugated dienes such as 1,5-heptadiene, 7-methyl-1,6-octadiene; cyclohexadiene;
Dicyclopentadiene, methyltetrahydroindene,
5-vinyl norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5
Cyclic non-conjugated dienes such as -isopropenyl-2-norbornene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene; Trienes such as 1,3,7-octatriene and 1,4,9-decatriene are mentioned, 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 and / or α-olefin aromatic vinyl compound copolymer rubber includes ethylene-aromatic vinyl compound copolymer rubber, α-olefin-aromatic vinyl compound copolymer rubber, ethylene-α- Olefin-aromatic vinyl compound copolymer rubber can be mentioned. Such aromatic vinyl compounds include p-methylstyrene, m-methylstyrene, o-methylstyrene, p-methylstyrene,
-Ethylstyrene, m-ethylstyrene, o-ethylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene, 3,5-dimethylstyrene, 3-methyl-5-ethylstyrene , Pt
alkylstyrenes such as tert-butylstyrene and p-sec-butylstyrene; styrene, 2-phenyl-1
Alkenylbenzenes such as propylene and 2-phenyl-1-butene; bisalkenylbenzenes such as divinylbenzene; vinylnaphthalenes such as 1-vinylnaphthalene. Among these alkenyl aromatic compounds, styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, p-tert-butylstyrene, 2-phenylpropylene, divinylbenzene and 1-vinylnaphthalene are more preferable, and styrene Is particularly preferred. The content of the aromatic vinyl compound is 5 to 5.
It is 50% by weight, preferably 10 to 35% by weight. α-
As the olefin, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-
Examples thereof include octene and 1-decene, among which propylene, 1-butene, 1-hexene and 1-octene are preferred. The content of the aromatic vinyl compound is 5 to 50% by weight, preferably 10 to 35% by weight. Such copolymers can be used in combination of two or more.

As the thermoplastic elastomer, styrene thermoplastic elastomer, olefin thermoplastic elastomer, urethane thermoplastic elastomer, ester thermoplastic elastomer, amide thermoplastic elastomer,
Vinyl chloride-based thermoplastic elastomers, 1,2-polybutadiene, trans 1,4-polyisoprene, ionomers and the like, and styrene-based thermoplastic elastomers,
Olefin thermoplastic elastomers, 1,2-polybutadiene, trans 1,4-polyisoprene, and ionomers are preferred. Styrene-based thermoplastic elastomers include styrene-butadiene-styrene copolymer, styrene-isoprene-styrene copolymer, hydrogenated styrene-butadiene-styrene copolymer, and hydrogenated styrene-isoprene-styrene copolymer And hydrogenated styrene-butadiene rubber and the like, and olefin-based thermoplastic elastomers include a reactor TPO and the like.
An oil-extended rubber containing oil as a rubber component may be used.

As the oil, there is a mineral oil, and examples thereof include paraffinic, naphthenic and aroma-based oils, and paraffinic oils are preferred.

In the present invention, in addition to the rubber component and the resin component, inorganic fillers (talc, calcium carbonate, calcined kaolin, etc.), organic fillers (fiber, wood powder, cellulose powder, etc.), lubricants (fatty acid amide, silicone, etc.) ),
Antioxidants (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 stability Agents (hindered amines, benzoates, etc.), antistatic agents, nucleating agents, pigments and the like may be used.

The rubber component of the present invention is arbitrarily selected from two or more types. As a selection method, it is preferable that the viscosity of the rubber component forming the isolated phase is larger than the viscosity of the rubber component forming the continuous phase and / or the network-like phase. If the viscosity of the rubber component forming the isolated phase and the continuous phase and / or the network-like phase is almost the same, only the isolated phase or only the continuous phase may be formed. As another selection method, at least one rubber component selects a diene rubber component having a double bond in the structure, and at least one other rubber component selects a non-diene rubber component having no double bond. It is preferable to select. Natural rubber as a diene rubber component,
Isoprene rubber, butadiene rubber, styrene-butadiene rubber, ethylene-α-olefin conjugated diene copolymer rubber, styrene-butadiene-styrene copolymer, and styrene-isoprene-styrene copolymer are preferred. Examples of the non-diene rubber component include a hydrogenated styrene-butadiene-styrene copolymer and a hydrogenated styrene-
Preferred are isoprene-styrene copolymer, hydrogenated styrene-butadiene rubber, ethylene and / or α-olefin aromatic vinyl compound copolymer, ethylene-α-olefin copolymer rubber, and reactor TPO. When a selection is made by a combination of a diene rubber and a non-diene rubber, an isolated phase and a continuous phase are easily formed by dynamic heat treatment under a crosslinking agent. The phase structure of the thermoplastic elastomer composition of the present invention is formed from a resin component and two or more rubber components, at least one rubber component forms a continuous phase and / or a network-like phase, and at least one other rubber component. Is a structure forming an isolated phase.

The isolated phase is a phase in which the same component (rubber component) is not continuous but dispersed alone in a cross-sectional observation of the thermoplastic elastomer composition, or a phase in which the continuous component is dispersed in particles.
Examples of the shape include a circle, an ellipse, a needle, and an irregular shape. Also, composites of various shapes may be used. The size of the isolated phase is preferably 500 μm or less on average, and more preferably 50 μm or less on average. However, for shapes other than circles, the size is defined by the circumscribed circle diameter. If the shape is a circle or a shape close to a circle, the average is preferably 10 μm or less. If the isolated phase is large, the appearance becomes poor and the appearance deteriorates.

The continuous phase is a phase in which the same component (rubber component) is completely or incompletely continuous and dispersed completely and partially in the cross-sectional observation of the thermoplastic elastomer composition.
The overall continuous phase is to form a continuous phase throughout the thermoplastic elastomer composition, and the partial continuous phase is to form a continuous phase in some areas of the thermoplastic elastomer composition. A perfect continuous phase is a continuous phase without an isolated phase,
An incomplete continuous phase is a continuous phase that forms a partially isolated phase.

The network-like phase is a phase that connects and isolates the isolated phases in the cross-sectional observation of the thermoplastic elastomer composition, and that is totally or incompletely continuous and dispersed. The overall continuous phase is to form a continuous phase throughout the thermoplastic elastomer composition, and the partial continuous phase is to form a continuous phase in some areas of the thermoplastic elastomer composition. The complete continuous phase is a continuous phase without an isolated phase, and the incomplete continuous phase is a continuous phase partially forming an isolated phase.

The resin component forms a phase in the space excluding the rubber component, and forms an isolated phase and / or a continuous phase.

The thermoplastic elastomer composition of the present invention may be melt-kneaded using a continuous or batch kneader. Examples of the continuous kneader include a single screw extruder and a twin screw extruder, and examples of the batch kneader include a kneader and a Banbury mixer. Resin component,
Depending on the shape of the rubber component, a batch type or a continuous type may be used together. If necessary, heat treatment may be dynamically performed using a crosslinking agent and a crosslinking agent and a crosslinking assistant.

The resin component and the rubber component may be charged by adding at least one rubber component to the kneader by mixing the resin component, the rubber component of the isolated phase, and the rubber component of the continuous phase and / or the network phase. A continuous phase and / or a network-like phase may be formed, and at least one other rubber component may form an isolated phase. The resin component and the rubber component of the isolated phase are put into a kneader, kneaded, and melt-dispersed. It is better to put the rubber of the continuous phase and / or the network phase into the kneader. When the heat treatment is performed dynamically, even if the resin component, the rubber component of the isolated phase, and the rubber component of the continuous phase and / or the network phase are put into the kneader, the resin component and the rubber component of the isolated phase are supplied to the kneader. After charging and dynamically heat-treating, a continuous phase and / or a network-like phase rubber component may be charged into the kneader, but an isolated phase rubber component, a continuous phase and / or a network-like phase rubber component may be added. When a non-diene rubber component is selected for both a diene rubber component or an isolated phase rubber component and a continuous phase and / or a network phase rubber component, be sure to put the resin component and the isolated phase rubber component into the kneader. After the heat treatment, the rubber component of the continuous phase and / or the network phase is charged into the kneader.

Examples of the crosslinking agent include sulfur, organic peroxides, phenolic resins and the like, and organic peroxides are preferred. As an organic peroxide, 2,5-dimethyl-2,5-
Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne,
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 the crosslinking aid, a compound having two or more double bonds in the molecular structure is preferable. N, N 'as crosslinking aid
-M-phenylenebismaleimide, toluylenebismaleimide, p-quinonedioxime, nitrosobenzene, diphenylguanidine, trimethylolpropane, trimethylolpropane trimethacrylate, divinylbenzene and the like.

The thermoplastic elastomer of the present invention is used for extrusion molding, injection molding, press molding, blow molding, powder molding and the like. It is preferably used for applications such as automobiles, railways, airplanes, ships, and the like, home electric appliance components, civil engineering and construction components, stationery, miscellaneous goods, and the like, which have scratch-resistant performance.

[0025]

The present invention will be described in more detail by the following examples.
explain. [I] Raw material rubber component (A) Ethylene-α-olefin copolymer rubber A-1; Mooney viscosity (ML_{1 + 4}100 ° C.) = 79
Oil-extended ethylene-propylene-conjugated diene copolymer rubber
[Conjugated diene; ENB oil extension 40 parts] (EPDM) (B) Hydrogenated styrene-butadiene-styrene
Copolymer B-1; Tuftec H1042 (SEBS) manufactured by Asahi Kasei Corporation (C) Ethylene-styrene copolymer C-1; MP189 (ESC) MP189 is a 100-L SUS polymerization equipped with a stirring blade.
Copolymerization of ethylene and styrene continuously using a vessel
Was. That is, hexane was used as the polymerization solvent from the bottom of the polymerization vessel.
84.7 kg / h, ethylene 2.8 kg / h,
Continuous supply of 4.15 kg / hr of styrene.
On the other hand, the amount of the polymerization liquid in the polymerization vessel from the top of the polymerization vessel became 100 L.
The polymerization liquid is continuously withdrawn as described above. Isop as catalyst
Lopylidene (cyclopentadienyl) (3-tert-
Butyl-5-methyl-2-phenoxy) titanium
Chloride, N, N-dimethylanilinium tetrakis (pe
Nantafluorophenyl) borate and triisobutyl
0.348 g / hour of aluminum, 1.08
1 g / hr, 6.912 g / hr
Continuously fed into the polymerization vessel. The copolymerization reaction is carried out in a polymerization vessel.
Circulates cooling water through an externally mounted jacket
This was performed at 50 ° C. To the polymerization liquid extracted from the polymerization vessel
Stop the polymerization reaction by adding a small amount of ethanol and remove
After washing with nomer and water, the solvent is removed by steam in a large amount of water.
After removing the copolymer, it was dried under reduced pressure at 80 ° C day and night.
Was. By the above operation, ethylene-styrene copolymerization is 2
It was performed at a rate of kg / hour. Ubero of this copolymer
135 ° C using tetralin as a solvent with a thermometer
The intrinsic viscosity [η] measured in 2.3 was 2.31. Differential
Using a thermal analyzer (DSC220 manufactured by Seiko Denshi Kogyo)
The melting curve was determined at a heating rate of 10 ° C./min.
The point was 44 ° C and the glass transition point was -20 ° C. ¹³C-
NMR (JNM-EX270 manufactured by JEOL Ltd., measurement solvent
Orthodichlorobenzene, measurement temperature 135 ° C) For analysis
The styrene content determined from the above was 16 mol%.
3 for the area of the peak appearing at 0-38.0 ppm
The ratio of the areas of the peaks appearing at 4.0 to 36.0 ppm is as follows:
It was 0.019. Resin component (D) Propylene resin D-1; MFR (230 ° C., 21.18 N) = 65 g /
Propylene-ethylene block copolymerization for 10 min
Body (BLOCK-PP)

[II] Measurement Method The obtained composition was molded at 200 ° C. using a press molding machine into a flat plate having a thickness of 2 mm and a size of 150 mm × 150 mm, and then required measurements were performed. Scratch resistance test; scratches by scratching the surface of a plate press-formed with a scratching needle loaded with a load of 300 g at a constant speed using a surface property measuring machine Tribogear (manufactured by Shinto Kagaku), and visually observes the scratches Was evaluated. ；: Good (scratch is not so conspicuous) ×: bad (scratch is conspicuous) Phase observation: stained with _{RuO 4} and observed with a transmission electron microscope

Example 1 and Comparative Example 1 The composition shown in Table 1 and 0.1 part by weight of trimethylolpropane trimethacrylate as a crosslinking aid and 2,5 as a crosslinking agent were used.
0.128 parts by weight of -dimethyl-2,5-di (t-butylperoxy) hexine was charged in two portions, and dynamically heat-treated with a Labo Plastomill. The obtained composition was molded and measured. Table 1 shows the results.

[0028]

[Table 1]

[0029]

As described above, according to the present invention, a thermoplastic elastomer composition having excellent scratch resistance and a method for producing the same can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of the definition of the shape and size of an isolated phase.

FIG. 2 is a schematic diagram of an isolated phase and a continuous phase.

FIG. 3 is a schematic view of a partial continuous phase and an entire continuous phase.

FIG. 4 is a schematic diagram of an incomplete continuous phase and a complete continuous phase.

FIG. 5 is a schematic diagram of a network-like phase and a continuous phase.

FIG. 6 is a transmission micrograph of Example 1.

FIG. 7 is a transmission microscope photograph of Comparative Example 1.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Eiji Nakaishi 5-1, Anesaki Beach, Ichihara-shi, Chiba F-term (reference) 4F070 AA05 AA06 AA07 AA08 AA09 AA12 AA13 AA15 AA18 AA22 AA50 FA03 FB07 FC05 4J002 AC01X AC02X AC06X AC07X AC09X BB01W BB15X BC02W BD03W BG02W CG00W

Claims (4)

[Claims] 1. A thermoplastic resin comprising a resin component and two or more rubber components, wherein at least one rubber component forms a continuous phase and / or a network-like phase, and at least one other rubber component forms an isolated phase. Elastomer composition. 2. The thermoplastic elastomer according to claim 1, wherein at least one rubber component is a rubber component having a double bond in the structure, and at least one other rubber component is a rubber component having no double bond. Composition. 3. The thermoplastic elastomer composition according to claim 1, wherein the resin component is an olefin resin or a styrene resin. 4. A rubber component forming an isolated phase with a resin component is charged into a kneader, melt-kneaded or dynamically heat-treated, and then a rubber component forming a continuous phase and / or a network-like phase is charged. Item 10. A method for producing the thermoplastic elastomer composition according to Item 1.