JP2018204032A - Thermoplastic elastomer composition - Google Patents

Abstract

[PROBLEMS] To provide a thermoplastic elastomer composition having excellent moldability and flexibility, and having high compression set resistance, gas barrier properties and moisture permeability resistance even at high temperatures, and a molded article obtained by using the composition. To do. A component A contains an aromatic vinyl polymer block and a structural unit derived from isoprene, and the total content of 1,2-linkage units and 3,4-linkage units is 45 mol% or more. A hydrogenated block copolymer having an isoprene-based polymer block and a hydrogenated block copolymer having a weight-average molecular weight of 150,000 to 500,000, and a kinematic viscosity at 40 ° C of 3,000 to 20,000 mm2 / s polybutene oil, component C: polyolefin, and component D: a thermoplastic elastomer composition comprising a triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene-based polymer block, and A molded article obtained using the composition. [Selection diagram] None

Description

The present invention is useful for various molded articles such as automobiles, electronic materials, home appliances, electrical equipment, medical equipment, packaging materials, stationery and miscellaneous goods, and further grips, tubes, packings, gaskets, cushion bodies, films, and sheets. The present invention relates to a thermoplastic elastomer composition used for various members such as, and a molded body obtained by using the composition.

Conventionally, rubbers obtained by blending a rubber such as natural rubber or synthetic rubber with a crosslinking agent or a reinforcing agent and crosslinking under high temperature and high pressure have been widely used as a polymer material having elasticity. However, such rubbers require a process of crosslinking and molding for a long time under high temperature and high pressure, and are inferior in processability. Moreover, since the crosslinked rubber does not exhibit thermoplasticity, it is generally impossible to perform recycle molding like a thermoplastic resin. For this reason, various thermoplastic elastomers have been developed in recent years that can easily produce molded products using general-purpose melt molding techniques such as hot press molding, injection molding, and extrusion molding, as with ordinary thermoplastic resins. Yes.

Conventionally, a polymer block (A) containing a structural unit derived from an aromatic vinyl compound and a structural unit derived from isoprene or a mixture of isoprene and butadiene, and a 3,4-bond unit and a 1,2-bond A hydrogenated product of a block copolymer having a polymer block (B) having a total content of units of 45% or more, and a thermoplastic elastomer composition containing a softener and a polyolefin resin are used as a medical sealant. And is known to exhibit liquid leakage resistance and oxygen barrier properties (see Patent Document 1).

On the other hand, Patent Document 2 is selected from a composition obtained by crosslinking an isobutylene polymer having an alkenyl group at a terminal with a hydrosilyl group-containing polysiloxane, a polybutene oil, a polyolefin resin, and an aromatic vinyl block copolymer. A thermoplastic elastomer composition having improved compression set characteristics and gas barrier properties using at least one component is disclosed.

International Publication No. 2011/40586 JP-A-2005-68224

However, the thermoplastic elastomer composition described in Patent Document 1 does not have sufficient compression set resistance, and when used in the packing of the connection portion, the compression deformation does not return well, and a gap is formed in the connection portion. There is a possibility that the tube inserted into the tube will be bent and closed or fall off.

Further, the thermoplastic elastomer composition described in Patent Document 2 has poor melt fluidity, tends to roughen the surface when molded, and the polybutene oil tends to bleed out, and the surface of the molded article may become sticky. There is. Furthermore, although there is a description that the gas barrier property was measured with air in accordance with the JIS K 7126A method in the examples, there is no subject of the invention regarding the water vapor permeability, and what shows the effect of moisture permeability resistance Is not known about.

In general, it is known that the permeability of nonpolar gas with respect to a single polymer material is easier to permeate as the gas molecules are smaller, but in the case of an elastomer composition, the contained components and how to mix them Since the gas permeability is affected by the morphology and the like, it is difficult to predict the permeability. When the polar gas such as water vapor is transmitted, the influence of the chemical composition is further increased, and the conventional measurement conditions of 40 ° C and relative humidity of about 90%, which are conventionally defined by JIS K 7129, are common knowledge. There is no known problem or means for reducing the water vapor permeability at higher temperatures.

On the other hand, not only automobile applications, but also household appliances, elastic parts are exposed to higher temperatures as household appliances become smaller and denser. The thing which demonstrates the performance of is demanded. When the temperature rises, the saturated water vapor pressure rises exponentially. For example, the saturated water vapor pressure at 70 ° C is about 4 times that of 40 ° C. Even what was thought to be, it can happen that it cannot withstand use in higher temperature environments. That is, there is a need for thermoplastic elastomer compositions and molded articles that exhibit high moisture permeability resistance even at high temperatures in addition to properties such as moldability, flexibility, and compression set resistance.

An object of the present invention is to provide a thermoplastic elastomer composition which is excellent in moldability and flexibility and has high compression set resistance, gas barrier property and moisture permeability resistance even at high temperatures, and molding obtained using the composition. To provide a body.

The present invention
[1] Component A: Isoprene containing an aromatic vinyl polymer block and a structural unit derived from isoprene, and the total content of 1,2-bond units and 3,4-bond units is 45 mol% or more A hydrogenated block copolymer having a polymer block and a hydrogenated block copolymer having a weight average molecular weight of 150,000 to 500,000,
Component B: polybutene oil having a kinematic viscosity at 40 ° C. of 3,000 to 20,000 mm ² / s,
Component C: Polyolefin, and Component D: Triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene polymer block
Containing
Thermoplastic, wherein the content of component B is 10 to 200 parts by mass, the content of component C is 1 to 200 parts by mass, and the content of component D is 50 to 1200 parts by mass with respect to 100 parts by mass of component A An elastomer composition,
And [2] relates to a molded article comprising the thermoplastic elastomer composition according to [1].

The thermoplastic elastomer composition of the present invention is excellent in moldability and flexibility, and has the effect of having high compression set resistance, gas barrier properties and moisture permeability resistance even at high temperatures.

The thermoplastic elastomer composition of the present invention (hereinafter also referred to as the composition of the present invention)
Component A: A structural unit derived from an aromatic vinyl polymer block and isoprene or a mixture of isoprene and butadiene, and the total content of 1,2-bond units and 3,4-bond units is 45
A hydrogenated block copolymer having a weight average molecular weight of 150,000 to 500,000, which is a hydrogenated product of a block copolymer having an isoprene-based polymer block that is at least mol%,
Component B: polybutene oil having a kinematic viscosity at 40 ° C. of 3,000 to 20,000 mm ² / s,
Component C: Polyolefin, and Component D: Crosslinked isobutylene polymer D1, and / or triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene polymer block
It contains.

The hydrogenated block copolymer of component A is a hydrogenated product of a block copolymer having an aromatic vinyl polymer block and an isoprene-based polymer block.

The aromatic vinyl polymer block contains a structural unit derived from an aromatic vinyl compound (hereinafter also referred to as an aromatic vinyl compound unit). Examples of the aromatic vinyl compound include styrene,
α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
1,3-dimethylstyrene, vinyl naphthalene, etc. are mentioned, and two or more of these may be used in combination. Of these, styrene, which is easily available, is preferable.

The aromatic vinyl polymer block may contain a structural unit derived from a monomer other than the aromatic vinyl compound as long as the effects of the present invention are not impaired. Examples of other monomers include copolymerizable monomers such as 1-butene, pentene, hexene, butadiene, isoprene, and methyl vinyl ether that can be ionically polymerized. The content of the aromatic vinyl compound unit in all the structural units constituting the aromatic vinyl polymer block is preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more.

The isoprene-based polymer block contains structural units derived from isoprene or a mixture of isoprene and butadiene, and contains a high content of 1,2-bond units and 3,4-bond units. The structural unit derived from isoprene (hereinafter also referred to as isoprene unit) includes:
Depending on the carbon attached to the structural units on both sides, there are 1,2-bond units, 3,4-bond units, and 1,4-bond units. Among these, the 1,2-bond unit and the 3,4-bond unit have a bulky alkyl group in the side chain compared to the 1,4-bond unit by hydrogenation because the carbon chain in the side chain contains a double bond. Will have a group. Similarly, structural units derived from butadiene (hereinafter also referred to as butadiene units) include 1,2-bond units, 3,4-bond units, and 1,4-bond units. The bond unit and the 3,4-bond unit are regarded as substantially the same structural unit. In the present invention, the gas barrier property of the thermoplastic elastomer composition is improved by containing a large amount of 1,2-bond units and 3,4-bond units whose side chains become bulky by hydrogenation.

The total content of 1,2-bond units and 3,4-bond units is 45 mol% or more, preferably 47 mol, from the viewpoint of gas barrier properties in all the structural units constituting the isoprene-based polymer block. %
Or more, more preferably 50 mol% or more, still more preferably 53 mol% or more, preferably
It is 95 mol% or less, more preferably 90 mol% or less, still more preferably 80 mol% or less, still more preferably 70 mol% or less. From these viewpoints, the total content of 1,2-bond units and 3,4-bond units is 45 mol% or more in all structural units constituting the isoprene-based polymer block, preferably 47 to 95. It is mol%, More preferably, it is 50-90 mol%, More preferably, it is 50-80 mol%, More preferably, it is 50-70 mol%, More preferably, it is 53-70 mol%.

When the isoprene-based polymer block contains both isoprene units and butadiene units,
The molar ratio (isoprene unit / butadiene unit) is preferably 50/50 to 95/5, more preferably 60/40 to 90/10, still more preferably 70/30 to 85/15.

The bonding form of the isoprene unit and the butadiene unit may be random, block, or tapered.

The isoprene-based polymer block may contain a structural unit derived from a monomer other than the isoprene unit and the butadiene unit as long as the effects of the present invention are not impaired. Other monomers include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, diphenylethylene, 1-vinylnaphthalene, 4-propylstyrene, Examples include anionic polymerizable copolymerizable monomers such as aromatic vinyl compounds such as 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, and 4- (phenylbutyl) styrene. In all the structural units constituting the isoprene-based polymer block, the content of the isoprene unit or the total content of the isoprene unit and the butadiene unit is preferably 80% by mass or more, more preferably 90% by mass from the viewpoint of gas barrier properties. % Or more, more preferably 95% by mass or more.

In the present invention, a block copolymer having an aromatic polymer block and an isoprene-based polymer block is hydrogenated (sometimes abbreviated as “hydrogenated”). A part or all of unsaturated double bonds (carbon-carbon double bonds) in the combined block are hydrogenated. The hydrogenation rate of the isoprene-based polymer block is preferably 50% or more, more preferably 60% or more, more preferably 70% or more, and still more preferably
80% or more. The hydrogenation rate may be described as “hydrogenation rate of hydrogenated block copolymer”.

The hydrogenated block copolymer is a functional group such as a carboxyl group, a hydroxyl group, an acid anhydride group, an amino group, and an epoxy group in the molecular chain and / or at the molecular end, as long as the effects of the present invention are not impaired. 1 type (s) or 2 or more types may be included.

The hydrogenated block copolymer is a hydrogenated block copolymer containing at least one aromatic vinyl polymer block and an isoprene-based polymer block, preferably two or more aromatic vinyl polymer blocks. And a hydrogenated product of a block copolymer containing one or more isoprene-based polymer blocks. The bonding form of the aromatic vinyl polymer block and the isoprene polymer block is not particularly limited, and may be any of linear, branched, radial, or a combination of two or more thereof. , A linearly coupled form is preferred,
When the aromatic vinyl polymer block is represented by "A" and the isoprene-based polymer block is represented by "B", (AB) _l , A- (BA) _m , B- (AB) _n (Wherein, l, m and n each independently represents an integer of 1 or more) are preferred, and from the viewpoint of rubber elasticity, mechanical properties, handleability, etc., ( _AB ) _l And a bonding form represented by A- (B-A) _m, which is a bonding form of a diblock structure represented by AB or a triblock structure represented by ABA More preferably.

Further, when the hydrogenated block copolymer has two or more aromatic vinyl polymer blocks or two or more isoprene polymer blocks, each aromatic vinyl polymer block and isoprene polymer block are mutually connected. It may be a block having the same configuration or a block having a different configuration. For example, two aromatic vinyl polymer blocks in the triblock structure represented by [A-B-A] may be the same or different in the types of aromatic vinyl compounds constituting them. Good.

The content of the aromatic vinyl polymer block in the hydrogenated block copolymer of Component A is preferably 5 to 70% by mass or more, more preferably 15 to 50% by mass or more, from the viewpoint of flexibility and compression set. More preferably, it is 15 to 35% by mass or more.

In the hydrogenated block copolymer of Component A, the mass ratio of the aromatic vinyl polymer block to the isoprene polymer block (aromatic vinyl polymer block / isoprene polymer block)
Is preferably 5/95 to 70/30, more preferably 15/85 from the viewpoint of flexibility and gas barrier properties.
-50/50, more preferably 15 / 85-35 / 65.

The weight average molecular weight of the hydrogenated block copolymer of Component A is 150,000 or more from the viewpoint of improving compression set resistance and suppressing oil bleed, and is 500,000 or less from the viewpoint of fluidity and moldability. From these viewpoints, the weight average molecular weight of the hydrogenated block copolymer of component A is 150,
000 to 500,000, preferably 160,000 to 400,000, more preferably 170,000 to 350,000.

The content of Component A is preferably 5% by mass or more from the viewpoint of oil bleeding in the composition of the present invention, and preferably 80% by mass or less from the viewpoint of water vapor barrier properties. From these viewpoints, the content of component A in the composition of the present invention is preferably 5 to 80% by mass, more preferably 5 to 70% by mass, further preferably 7 to 65% by mass, and further preferably 10 to 10%. 50% by mass.

  Component B is polybutene oil.

The kinematic viscosity at 40 ° C. of polybutene oil is 3,000 mm ² / s or more from the viewpoint of improving long-term heat resistance and suppressing bleeding, and 20,000 mm ² / s or less from the viewpoint of moldability and gas barrier properties. From these viewpoints, the kinematic viscosity of polybutene oil at 40 ° C. is 3,000 to 20,000 mm ² / s, preferably 4,000 to 17,500 mm ² / s, more preferably 5,000 to 15,000 mm ² / s.

The content of Component B is 10 parts by mass or more with respect to 100 parts by mass of Component A from the viewpoint of flexibility and dispersibility during melt-kneading, and 200 parts by mass from the viewpoint of improving moldability and suppressing bleeding. It is as follows. From these viewpoints, the content of Component B is 10 to 200 parts by mass, preferably 15 to 100 parts by mass, and more preferably 20 to 75 parts by mass with respect to 100 parts by mass of Component A.

The content of component B is preferably 0.1 to 50% by mass, more preferably 0.5 in the composition of the present invention.
-30 mass%.

  Component C is a polyolefin.

Examples of the polyolefin include polyethylene, polypropylene, and ethylene-propylene copolymer. Among these, polypropylene is preferable from the viewpoint of heat resistance and compatibility.

The melting point of polyolefin is preferably 140 ° C. or higher from the viewpoint of long-term heat resistance, and preferably 200 ° C. or lower from the viewpoint of moldability. From these viewpoints, the melting point of the polyolefin is preferably 140 to 190 ° C, more preferably 145 to 185 ° C, and further preferably 150 to 180 ° C.

The melt mass flow rate of polyolefin at 230 ° C and 21N is 0.1% from the viewpoint of moldability.
g / 10 min or more is preferable, and from the viewpoint of heat resistance, 100 g / 10 min or less is preferable. From these viewpoints, the melt mass flow rate of polyolefin at 230 ° C. and 21 N is preferably 0.1-10.
0 g / 10 min, more preferably 0.5 to 80 g / 10 min, still more preferably 1.0 to 50 g / 10 min.

The flexural modulus of polyolefin is preferably 30 MPa or more from the viewpoint of gas barrier properties, and preferably 2500 MPa or less from the viewpoint of flexibility. From these viewpoints, the flexural modulus of polyolefin is preferably 50 to 2000 MPa, more preferably 100 to 1850 MPa, and still more preferably 200 to
1700MPa.

The content of Component C is 1 part by mass or more with respect to 100 parts by mass of Component A from the viewpoint of dispersibility during melt-kneading, and 200 parts by mass or less from the viewpoint of flexibility and compression set resistance. is there. From these viewpoints, the content of Component C is 1 to 200 parts by mass, preferably 5 to 175 parts by mass, more preferably 10 to 150 parts by mass, and even more preferably 15 parts, relative to 100 parts by mass of Component A. ~ 100 parts by mass,
More preferably, it is 20-80 mass parts.

The content of component C is preferably 0.1 to 50% by mass, more preferably 0.5% in the composition of the present invention.
-30 mass%.

Component D is a cross-linked isobutylene polymer D1 and / or a triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene polymer block.

The isobutylene-based polymer contains a structural unit derived from isobutylene (hereinafter also referred to as an isobutylene unit).

The isobutylene polymer may contain a structural unit derived from a monomer other than isobutylene as long as the effects of the present invention are not impaired. Other monomers include aliphatic olefins, alicyclic olefins, aromatic vinyls, dienes, vinyl ethers, silanes, vinyl carbazole, β-pinene, acenaphthylene and the like. Among all structural units constituting the isobutylene polymer, the content of isobutylene units is from the viewpoint of water vapor barrier properties at high temperatures,
Preferably it is 50 mass% or more, More preferably, it is 60 mass% or more, More preferably, it is 70 mass% or more.

The crosslinked isobutylene polymer D1 is preferably a hydrosilylation-crosslinked isobutylene polymer having an allyl group from the viewpoint of hygiene and compression set resistance.

The isobutylene polymer having an allyl group can be obtained by introducing an allyl group into the isobutylene polymer by the following method or the like. As a method for introducing an unsaturated group into a polymer having a functional group such as a hydroxyl group, a method for introducing an unsaturated group into the polymer by reacting a polymer having a functional group such as a hydroxyl group with a compound having an unsaturated group Etc. In addition, as a method for introducing an unsaturated group into a polymer having a halogen atom, a method of performing a Friedel-Crafts reaction with an alkenylphenyl ether, a method of performing a substitution reaction with allyltrimethylsilane in the presence of a Lewis acid, and the like. And a method of performing the alkenyl group introduction reaction after introducing a hydroxyl group by performing a Friedel-Crafts reaction with phenols.

The amount of allyl group in the isobutylene polymer can be arbitrarily selected depending on the required properties, but from the viewpoint of the properties after crosslinking, the isobutylene polymer having an allyl group is 1
It is preferably a polymer having at least 0.2 allyl groups per molecule, more preferably a polymer having 1.0 or more allyl groups per molecule, and 1.5 or more allyl groups per molecule. More preferably, it is a polymer having a terminal group. The amount of allyl group in the isobutylene polymer can be measured by ¹ H-NMR spectrum analysis.

The hydrosilylation crosslinking of the isobutylene polymer can be performed, for example, by melt kneading with an extruder using a crosslinking agent having a plurality of hydrosilyl groups in the molecule and a platinum catalyst.

The cross-linking reaction improves the compression set resistance and heat resistance of the polymer, but also increases the hardness and melt viscosity at the same time, so when component D is used as the composition of the elastomer composition,
The molecular weight after crosslinking is preferably used as an index for selection from the viewpoint of blending without destroying the physical property balance of the entire composition.

The weight average molecular weight of the crosslinked isobutylene polymer D1 is preferably 50,000 or more from the viewpoint of suppressing compression set, and preferably 500,000 or less from the viewpoint of moldability. From these viewpoints, the weight average molecular weight of the crosslinked isobutylene polymer D1 is preferably 50,000 to 50.
It is 0,000, more preferably 55,000-450,000, still more preferably 75,000-425,000, still more preferably 100,000-400,000.

The triblock copolymer D2 having an aromatic vinyl polymer block and an isobutylene polymer block is preferably composed of two aromatic vinyl polymer blocks and one isobutylene polymer block. What provided the aromatic vinyl polymer block on both sides of the isobutylene-type polymer block is more preferable.

The aromatic vinyl polymer block contains an aromatic vinyl compound unit. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, vinylnaphthalene, and the like. You may use together. Of these, styrene, which is easily available, is preferable.

The aromatic vinyl polymer block may contain a structural unit derived from a monomer other than the aromatic vinyl compound as long as the effects of the present invention are not impaired. Examples of other monomers include copolymerizable monomers such as 1-butene, pentene, hexene, butadiene, isoprene, and methyl vinyl ether that can be ionically polymerized. The content of the aromatic vinyl compound unit in all the structural units constituting the aromatic vinyl polymer block is preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more.

  The isobutylene polymer block contains isobutylene units.

The isobutylene polymer block may contain a structural unit derived from a monomer other than isobutylene as long as the effects of the present invention are not impaired. Other monomers include aliphatic olefins, alicyclic olefins, aromatic vinyls, dienes, vinyl ethers, silanes, vinyl carbazole, β-pinene, acenaphthylene and the like. The content of isobutylene units in all structural units constituting the isobutylene polymer block is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably 70%, from the viewpoint of water vapor barrier properties at high temperatures. It is at least mass%.

The content of the isobutylene polymer block contained in the triblock copolymer D2 is preferably 50% by mass or more from the viewpoint of water vapor barrier properties at high temperatures, and preferably 90% by mass or less from the viewpoint of oil bleed. From these viewpoints, the content of the isobutylene polymer block contained in the triblock copolymer D2 is preferably 50 to 90% by mass, more preferably 55 to
It is 85 mass%, More preferably, it is 60-80 mass%.

Mass ratio of isobutylene polymer block and aromatic vinyl polymer block in triblock copolymer D2 (isobutylene polymer block / aromatic vinyl polymer block)
Is preferably 50/50 to 90/10, more preferably 55, from the viewpoint of water vapor barrier properties at high temperatures.
/ 45 to 85/15, more preferably 60/40 to 80/20.

The weight average molecular weight of the triblock copolymer D2 is 50,000 from the viewpoint of suppression of compression set.
The above is preferable, and from the viewpoint of moldability, 500,000 or less is preferable. From these viewpoints, the weight average molecular weight of the triblock copolymer D2 is preferably 50,000 to 500,000, more preferably 60,000 to 400.000, and still more preferably 70,000 to 300,000.

Content of component D is 50-1200 mass parts with respect to 100 mass parts of component A, and when both are used together, those total amounts shall be the said range.
When the crosslinked isobutylene polymer D1 is contained alone, the content thereof is 50 parts by mass or more with respect to 100 parts by mass of Component A from the viewpoint of water vapor barrier properties at high temperatures, From the viewpoint of smoothing the surface of the body and improving the appearance, it is 1200 parts by mass or less. From these viewpoints, the content of the crosslinked isobutylene polymer D1 is 100 parts by mass of component A.
It is 50-1200 mass parts, Preferably it is 100-1100 mass parts, More preferably, it is 200-1000 mass parts.
When triblock copolymer D2 is contained alone, the content thereof is 50 parts by mass or more with respect to 100 parts by mass of component A from the viewpoint of water vapor barrier properties at high temperatures, From the viewpoint of distortion, it is 1200 parts by mass or less. From these viewpoints, the content of the triblock copolymer D2 is 50 to 1200 parts by mass, preferably 100 to 1100 parts by mass, and more preferably 200 to 1000 parts by mass with respect to 100 parts by mass of the component A. .

The content of component D in the composition of the present invention is preferably 5 to 90% by mass, more preferably 10 to 8%.
5% by mass.

The composition of the present invention preferably contains Component E: polyphenylene ether from the viewpoint of the surface smoothness of the molded article.

The reduced viscosity of polyphenylene ether is the viscosity at 30 ° C. of a solution dissolved in chloroform at a concentration of 0.5 g / dL by a method based on JIS K 7367. From the viewpoint of compatibility, it is preferably 0.1 or more, and from the viewpoint of dispersibility and surface property of the molded article, it is preferably less than 0.45. From these viewpoints, the reduced viscosity of polyphenylene ether is preferably 0.1 to 0.45, more preferably 0.1.
It is 5 to 0.45, more preferably 0.2 to 0.45.

The glass transition temperature of polyphenylene ether is preferably 170 ° C. or higher from the viewpoint of heat resistance, and preferably 260 ° C. or lower from the viewpoint of moldability. From these viewpoints, the glass transition temperature of polyphenylene ether is preferably 170 to 260 ° C, more preferably 180 to 250 ° C, and further preferably 190 to 240 ° C.

The volume-median particle size of polyphenylene ether is preferably 0.1 μm or more from the viewpoint of dispersibility, and 1000 μm is preferable from the viewpoint of productivity (classification). From these viewpoints, the volume-median particle size of polyphenylene ether is preferably 0.1 to 1000 μm, more preferably 10 to 800 μm,
More preferably, it is 50-500 micrometers.

The content of Component E is preferably 1 part by mass or more with respect to 100 parts by mass of Component A, from the viewpoint of the surface smoothness of the molded article, and preferably 100 parts by mass or less from the viewpoint of compression set. From these viewpoints, the content of component E is preferably 1 to 100 parts by mass, more preferably 5 to 80 parts by mass, and still more preferably 10 to 70 parts by mass with respect to 100 parts by mass of component A.

The content of component E is preferably 0.1 to 30% by mass, more preferably 1.0 in the composition of the present invention.
~ 15% by weight.

The composition of the present invention preferably contains Component F: an inorganic filler from the viewpoint of water vapor barrier properties.

Inorganic fillers include talc, mica, calcium carbonate, clay, titanium oxide, magnesium carbonate, barium sulfate, calcium sulfate, calcium sulfite, calcium phosphate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, magnesium oxide, iron oxide, Zinc oxide, alumina, silica, diatomaceous earth, dolomite, gypsum, calcined clay, asbestos,
Calcium silicate, bentonite, white carbon, carbon black, iron powder, aluminum powder, stone powder, blast furnace slag, fly ash, cement, zirconia powder, etc.
Among these, talc is preferable from the viewpoint of water vapor barrier properties and dispersibility.

Inorganic fillers are known in various shapes such as granular, plate-like, rod-like, fiber-like, whisker-like, etc. In the present invention, plate-like ones are preferable from the viewpoint of water vapor barrier properties and gas barrier properties. . The plate shape refers to a shape having a major axis / thickness ratio (major axis / thickness) of 5 or more, preferably 10 to 500.

The volume median particle size of the plate-like inorganic filler is preferably 1.5 μm or more from the viewpoint of dispersibility,
From the viewpoint of flexibility, 150 μm or less is preferable. From these viewpoints, the volume median particle size of the plate-like inorganic filler is preferably 1.5 to 150 μm, more preferably 1.75 to 120 μm, and still more preferably 2.0 to 15 μm.

The content of Component F is preferably 1 part by mass or more with respect to 100 parts by mass of Component A from the viewpoint of water vapor barrier properties, and preferably 500 parts by mass or less from the viewpoint of surface properties of the molded body. From these viewpoints, the content of Component F is preferably 1 to 500 parts by mass, more preferably 20 to 400 parts by mass, and still more preferably 50 to 350 parts by mass with respect to 100 parts by mass of Component A. Moreover, when an inorganic filler is plate shape, from a viewpoint of water vapor | steam barrier property and tube smoothness, 250 mass parts or less are preferable, and 200 mass parts or less are more preferable.

The content of component F in the composition of the present invention is preferably 1 to 50% by mass, more preferably 5 to 35.
% By mass.

The composition of the present invention is, as necessary, a reinforcing agent such as carbon black, silica, carbon fiber, glass fiber, etc. within the range not impairing the effects of the present invention; insulating heat conductive filler, pigment, flame retardant, charging You may contain various additives, such as an inhibitor, a mold release agent, a tackifier, a crosslinking agent, a crosslinking adjuvant, a foaming agent, and a fragrance | flavor.

The composition of the present invention may contain other thermoplastic resins and thermoplastic elastomers as long as the effects of the present invention are not impaired.

The composition of the present invention may contain a polar elastomer for the purpose of modifying the polar resin. The polar elastomer is not particularly limited, and examples thereof include NBR (nitrile rubber), polyurethane rubber, epichlorohydrin rubber, polyurethane-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, and the like.

The composition of the present invention is preferably obtained by a method in which a raw material mixture containing Component A to Component D and, if necessary, Component E, Component F and the like is heated and kneaded with an extruder or a kneader.

“Mixing” as used in the present invention is not particularly limited as long as various components are mixed well, and various components may be dissolved and mixed in a soluble organic solvent, or the raw material may be heated. Then, they may be mixed by melt kneading.

In the present invention, when the component D contains a cross-linked isobutylene polymer D1, the cross-linked isobutylene polymer D1 is melt-mixed with at least a part of the polybutene oil of component B and / or the polyolefin of component C. It is preferable that Flexibility is improved by previously melt-mixing the crosslinked isobutylene polymer D1 with the component B. Moreover, long-term heat resistance improves by melt-mixing the cross-linked isobutylene polymer D1 with the component C.

The amount of component B previously melt-mixed with the crosslinked isobutylene polymer D1 is preferably 10 to 50 parts by mass, more preferably 15 to 45 parts by mass with respect to 100 parts by mass of the crosslinked isobutylene polymer D1. Part. In addition, the amount of the component C previously melt-mixed with the crosslinked isobutylene polymer D1 is preferably 100 parts by mass with respect to the crosslinked isobutylene polymer D1.
1 to 20 parts by mass, more preferably 3 to 15 parts by mass.

“SIBSTAR P1140B” (manufactured by Kaneka Corporation) or the like can also be used as a commercial product of such an isobutylene polymer D1 previously melt-mixed with component B and component C.

Examples of the extruder include a single screw extruder, a parallel screw twin screw extruder, and a conical screw twin screw extruder. In the present invention, from the viewpoint of excellent mixing ability (the resulting mixture has good dispersibility), a twin screw extruder is preferred, and a co-rotating twin screw extruder is more preferred.

The die attached to the discharge part of the extruder can be selected arbitrarily. For example, a strand die suitable for pellet production, a T die suitable for sheet or film production, a pipe die, a profile extrusion die, etc. Can be mentioned.

Moreover, the extruder may be provided with a vent for venting gas connected to an air release portion or a decompression device, or may be provided with a plurality of raw material inlets.

The kneader means a batch-type mixer capable of controlling the temperature, and examples include a Banbury mixer, a Brabender plastograph, and a lab plast mill.

Each component may be charged into the extruder or kneader all at once, separately, or dividedly.

The composition of the present invention can be formed into a pellet, powder, sheet or the like depending on the application. For example, it is melt-kneaded by an extruder, extruded into strands, and cut into pellets such as cylindrical or rice grains by a cutter while cooling in cold water. The resulting pellet is usually
A predetermined sheet-like molded product or a die-molded product is obtained by injection molding or extrusion molding. Further, the melt-kneaded product can be formed into pellets with a ruder or the like and used as a forming raw material. It is good also as an intermediate product which stuck the mount etc. to the sheet-like thermoplastic elastomer composition.

The composition of the present invention is not particularly limited, and is a general styrene elastomer, polyolefin elastomer, polyurethane elastomer, polyamide elastomer,
It can be used in fields where acrylic elastomers and polyester elastomers are used.

The A hardness of the composition of the present invention is preferably 10 to 95, more preferably 20 from the viewpoint of flexibility.
~ 90, more preferably 40-90.

  A molded body is obtained by appropriately heat-molding the composition of the present invention according to a conventional method.

The temperature at the time of heat molding is preferably 150 to 250 ° C, more preferably 170 to 230 ° C, from the viewpoint of the appearance of the molded body.

The apparatus used for manufacturing the molded body using the composition of the present invention can be any molding machine capable of melting the molding material. Examples thereof include a kneader, an extrusion molding machine, an injection molding machine, a press molding machine, a blow molding machine, and a mixing roll.

Specific examples of the shape of the molded body using the composition of the present invention include a cylindrical molded body, a molded body for sealing,
A sheet-like molded object etc. are mentioned. The cylindrical molded body is a tube for an inkjet recording device, a catheter, a tube for infusion, a tube for peritoneal dialysis, a tube for blood transfusion, a medical tube such as a blood circuit tube used for cardiopulmonary or hemodialysis, etc., gas, liquid, semi-solid And various industrial tubes used for transferring these mixtures and the like. Moreover, the molded object for sealing can be used as various packings, seals, gaskets, solar cell sealing materials, food liner materials, and the like.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Various physical properties of the raw materials used in Examples and Comparative Examples were measured by the following methods.

<Component A>
[Content of aromatic vinyl compound unit in aromatic vinyl polymer block]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Total content of 1,2-bond units and 3,4-bond units in isoprene-based polymer blocks]
Dissolve the block copolymer before hydrogenation in CDCl ₃ and measure ¹ H-NMR spectrum [Apparatus: JNM
-Lambda 500 (manufactured by JEOL Ltd.), measuring temperature: 50 ° C], isoprene, butadiene,
Or the total peak area of structural units derived from a mixture of isoprene and butadiene, 1,2-bond units and 3,4-bond units in isoprene units, 1,2-bond units in butadiene units, and mixtures of isoprene and butadiene. In some cases, the total content of 3,4-bond units and 1,2-bond units is calculated from the ratio of peak areas corresponding to the respective bond units.
[Hydrogenation rate of hydrogenated block copolymer]
The iodine value of the block copolymer before and after hydrogenation is measured, and the hydrogenation rate (%) of the hydrogenated block copolymer is calculated from the following formula.

[Content of isoprene unit and / or butadiene unit in isoprene-based polymer block]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Contents of aromatic vinyl polymer block and isoprene polymer block in block copolymer]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Weight average molecular weight of block copolymer (Mw)]
Under the following measurement conditions, the molecular weight is measured in terms of polystyrene by gel permeation chromatography, and the weight average molecular weight is determined.
Measuring device and pump: JASCO (JASCO Corporation), PU-980
・ Column oven: Showa Denko KK, AO-50
・ Detector: Hitachi, RI (differential refractometer) detector L-3300
Column type: “K-805L (8.0 × 300mm)” and “K-804L (8.0 × 300mm)” manufactured by Showa Denko KK
1 each in series. Column temperature: 40 ° C
・ Guard column: KG (4.6 × 10mm)
・ Eluent: Chloroform ・ Eluent flow rate: 1.0 ml / min
・ Sample concentration: about 1mg / ml
・ Sample solution filtration: 0.45μm pore size disposable filter made of polytetrafluoroethylene ・ Standard sample for calibration curve: Polystyrene made by Showa Denko KK

<Component B>
(Kinematic viscosity)
Measured at a temperature of 40 ° C. according to JIS Z 8803.

<Component C>
[Melting point]
Using a differential scanning calorimetry (DSC) device, 10 ° C / min according to the method specified in JIS K 7121
The temperature of the melting peak obtained by raising the temperature at is set as the melting point. When a plurality of melting peaks appear, the melting peak appearing at a lower temperature is taken as the melting point.
[Melt Mass Flow Rate (MFR)]
Measured at 230 ° C by a method according to ASTM D 1238.
(Flexural modulus)
Measured by a method based on JIS K7171.

<Component D>
[Content of Isobutylene Unit in Crosslinked Isobutylene Polymer D1]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Weight average molecular weight (Mw) of crosslinked isobutylene polymer D1]
It is measured in terms of polystyrene by gel permeation chromatograph (GPC) measurement using chloroform as an eluent.
[Content of aromatic vinyl compound unit in aromatic vinyl polymer block of triblock copolymer D2]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Content of Isobutylene Unit in Isobutylene Polymer Block of Triblock Copolymer D2]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Contents of Aromatic Vinyl Polymer Block and Isobutylene Polymer Block Included in Triblock Copolymer D2]
Measurement is performed using a nuclear magnetic resonance apparatus (manufactured by BRUKER, Germany, DPX-400).
[Weight average molecular weight (Mw) of triblock copolymer D2]
It is measured in terms of polystyrene by gel permeation chromatograph (GPC) measurement using chloroform as an eluent.

<Component E>
[Reduced viscosity]
3 of a solution dissolved in chloroform at a concentration of 0.5 g / dL by a method according to JIS K 7367
Measure the viscosity at 0 ° C.
[Glass transition temperature (Tg)]
Measured by the DSC method by a method based on JIS K 7121.
(Volume median particle size)
50% cumulative particle size by volume based on laser diffraction method, D ₅₀ by a method based on JIS Z 8825
Measure.

<Component F>
(Volume median particle size)
50% cumulative particle size by volume based on laser diffraction method, D ₅₀ by a method based on JIS Z 8825
Measure.

Examples 1-20 and Comparative Examples 1-12
(1) Production of Thermoplastic Elastomer Composition (Pellets) Raw material components were charged into a mixer at a composition ratio (mass ratio) shown in Tables 7 to 11 and premixed. Thereafter, the obtained mixture was melt-kneaded by an extruder (continuous kneader) under the following conditions to produce pellets of a thermoplastic elastomer composition.
・ Extruder: KZW32TW-60MG-NH (manufactured by Technobel)
・ Cylinder temperature: 180-240 ℃
・ Screw rotation speed: 300r / min

  The detail of the raw material component used by the Example and the comparative example is shown to Tables 1-6.

(2) Fabrication of compact
(2-1) Injection-molded body The pellet was injection-molded under the following conditions to produce a plate having a width of 125 mm, a length of 125 mm, and a thickness of 2 mm.
[Injection molding conditions]
Injection molding machine: 100MSIII-10E (trade name, manufactured by Mitsubishi Heavy Industries, Ltd.)
Injection molding temperature: 200 ℃
Injection pressure: 30%
Injection time: 10sec
Mold temperature: 40 ℃

(2-2) Press-molded body The pellets were press-molded under the following conditions to prepare a sheet having a width of 20 cm, a length of 20 cm, and a thickness of 0.5 mm.
[Press molding conditions]
Press machine: 40ton electric hydraulic molding machine Heating temperature: Upper mold 200 ℃, Lower mold 200 ℃
Heating time: 5min
Press pressure: 5MPa
Cooling time: 2min

(2-3) Tube Molded Article The pellets were formed into a tube under the following conditions to produce a tube having an outer diameter of φ6.0 mm and an inner diameter of φ2.5 mm.
[Tube forming conditions]
Tube forming machine: Single screw extruder Cylinder temperature: 220 ℃

The following evaluation was performed about the composition obtained by the Example and the comparative example using the obtained molded object. The results are shown in Tables 7 to 11.

(1) Flexibility An injection molded body was used.
A hardness of 1 second measuring time in accordance with JIS K 6253 (a value after 1 second from the start of the test) was measured on three 2 mm-thick molded body samples (total 6 mm). The measurement was carried out after conditioning for one day in a room at a temperature of 23 ° C. and a humidity of 50%.

(2) Gas barrier property A press-molded body was used.
The oxygen transmission coefficient was measured by a method based on JIS K 7126.

(3) Water vapor barrier property A press-molded body was used.
The moisture permeability was measured under the environment of 40 ° C and 70 ° C.
Under 40 ° C environment: JIS K 0208 (cup method), conditions: 40 ° C x 90% RH, sheet thickness: 0.5 mm
70 ℃ environment: Measured by differential pressure method Measuring instrument: GTR-20XAGS (GTR Tech)
Test condition: 70 ± 0.1 ℃ × 90 ± 2% RH
Measurement area: 15.2cm ²
Sample shape: 90mm × 90mm × t = 0.5 ± 0.1mm

(4) Compression set resistance An injection molded article was used.
The compression set (CS) at 70 ° C. for 24 hours and 100 ° C. for 24 hours was measured by a method based on JIS K 6262.

(5) Formability A tube molded body was used.
(5-1) Surface property The surface of the tube was observed visually and tactilely and evaluated according to the following evaluation criteria.
1: The unevenness is extremely rough and the smoothness is extremely low.
2: Smoothness with noticeable roughness is low.
3: Although it is slightly rough, smoothness is not a problem.
4: It has sufficient smoothness.
5: The smoothness is extremely high.

(5-2) Stickiness The length of the tube 10 mm long was crushed and held for 5 seconds until the inner wall of the tube completely adhered, and then the time (sec) until the inner walls of the tube were released after the pressure was released was measured.

(5-3) Kink property The tube was cut to a length of 300 mm, and both ends of the tube were aligned and sandwiched between clips.
From both ends of the sandwiched tube, gently press and trace with your finger toward the center of the tube so that the two are in contact and in parallel, and stop the finger at the location where the center of the tube is buckled while tracing The distance from the part was measured.

From the above results, the thermoplastic elastomer compositions of Examples 1 to 20 are all flexible, moisture resistant under high temperature and compression set, and moldability as compared with Comparative Examples 1 to 12. It turns out that it is favorable.

The thermoplastic elastomer composition of the present invention is useful for various molded articles such as automobiles, electronic materials, home appliances, electrical equipment, medical equipment, packaging materials, stationery and miscellaneous goods, and further grips, tubes, packings, gaskets, Used for various members such as cushions, films and sheets.

The following are mentioned as an aspect of this invention.
[1] Component A: Containing an aromatic vinyl polymer block and a structural unit derived from isoprene or a mixture of isoprene and butadiene, and the total content of 1,2-bond units and 3,4-bond units is A hydrogenated block copolymer having an isoprene-based polymer block of 45 mol% or more, a hydrogenated block copolymer having a weight average molecular weight of 150,000 to 500,000,
Component B: polybutene oil having a kinematic viscosity at 40 ° C. of 3,000 to 20,000 mm ² / s,
Component C: Polyolefin, and Component D: Crosslinked isobutylene polymer D1, and / or triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene polymer block
Containing
Thermoplastic, wherein the content of component B is 10 to 200 parts by mass, the content of component C is 1 to 200 parts by mass, and the content of component D is 50 to 1200 parts by mass with respect to 100 parts by mass of component A Elastomer composition.
[2] The thermoplastic elastomer composition according to [1], wherein the polyolefin of component C has a melting point of 140 ° C. or higher.
[3] The thermoplastic elastomer composition according to the above [1] or [2], wherein among the components D, the isobutylene polymer D1 is obtained by hydrosilylation crosslinking of an isobutylene polymer having an allyl group.
[4] Among the components D, the triblock copolymer D2 has a weight average molecular weight of 50,000 to 500,000, and the content of the isobutylene polymer block contained in the triblock copolymer D2 is 50 to 90% by mass. The thermoplastic elastomer composition according to any one of [1] to [3].
[5] The thermoplastic elastomer composition according to any one of [1] to [4], further comprising Component E: polyphenylene ether.
[6] The thermoplastic elastomer composition according to the above [5], wherein the reduced viscosity of the polyphenylene ether of component E is less than 0.45.
[7] The thermoplastic elastomer composition according to any one of [1] to [6], further comprising Component F: 1 to 500 parts by mass of an inorganic filler with respect to 100 parts by mass of Component A.
[8] The thermoplastic elastomer composition according to [7], wherein the inorganic filler of component F is talc.
[9] The cross-linked isobutylene polymer D1 is formed by melt-mixing with at least a part of the component B polybutene oil and / or the component C polyolefin, according to any one of the above [1] to [8]. A thermoplastic elastomer composition.
[10] A molded article comprising the thermoplastic elastomer composition according to any one of [1] to [9].
[11] The molded body according to [10], which is a cylindrical molded body.
[12] The molded product according to [10], which is a molded product for sealing.

Claims (10)

Component A: an isoprene-based polymer containing an aromatic vinyl polymer block and a structural unit derived from isoprene, and the total content of 1,2-bond units and 3,4-bond units is 45 mol% or more A hydrogenated block copolymer having a block and a hydrogenated block copolymer having a weight average molecular weight of 150,000 to 500,000,
Component B: polybutene oil having a kinematic viscosity at 40 ° C. of 3,000 to 20,000 mm ² / s,
Component C: Polyolefin, and Component D: Triblock copolymer D2 composed of an aromatic vinyl polymer block and an isobutylene polymer block
Containing
Thermoplastic, wherein the content of component B is 10 to 200 parts by mass, the content of component C is 1 to 200 parts by mass, and the content of component D is 50 to 1200 parts by mass with respect to 100 parts by mass of component A Elastomer composition.   The thermoplastic elastomer composition according to claim 1, wherein the polyolefin of component C has a melting point of 140 ° C or higher.   The weight average molecular weight of the triblock copolymer D2 is 50,000 to 500,000, and the content of the isobutylene polymer block contained in the triblock copolymer D2 is 50 to 90% by mass. A thermoplastic elastomer composition.   Furthermore, the thermoplastic elastomer composition in any one of Claims 1-3 containing component E: polyphenylene ether.   The thermoplastic elastomer composition according to claim 4, wherein the reduced viscosity of the polyphenylene ether of component E is less than 0.45.   Furthermore, the thermoplastic elastomer composition in any one of Claims 1-5 which contain 1-500 mass parts of component F: an inorganic filler with respect to 100 mass parts of component A.   The thermoplastic elastomer composition according to claim 6, wherein the inorganic filler of component F is talc.   The molded object which consists of a thermoplastic-elastomer composition in any one of Claims 1-7.   The molded body according to claim 8, which is a cylindrical molded body.   The molded body according to claim 8, which is a molded body for sealing.