JP2020019947A - Thermoplastic elastomer composition, plug body and container - Google Patents

Abstract

To provide a thermoplastic elastomer composition that has excellent re-sealability, has low odor and can reduce the amount of eluted substances.SOLUTION: The thermoplastic elastomer composition includes 100 pts.mass of (a) a hydrogenated block copolymer, 10 to 50 pts.mass of a polypropylene-based resin, 75 to 200 pts.mass of (d) a nonaromatic softening agent and 1 to 150 pts.mass of (e) an inorganic filler. In the thermoplastic elastomer composition, the component (a) includes at least one polymer block A1 composed mainly of a vinyl aromatic hydrocarbon compound monomer unit and at least one polymer block B1 composed mainly of a conjugated diene compound monomer unit and contains (a-1) a hydrogenated block copolymer produced by hydrogenating a block copolymer; the weight average molecular weight of the component (a-1) is 100,000 to 550,000; the content of the whole vinyl aromatic hydrocarbon compound monomer units in the component (a-1) is more than 20 mass% to 50 mass%; and the component (e) is surface-treated silica.SELECTED DRAWING: None

Description

  The present invention relates to a thermoplastic elastomer composition, a plug, and a container.

In a medical container such as an infusion bag, the content liquid may remain in the medical container even after use. If the syringe needle is removed from the stopper attached to the medical container in a state where the content liquid remains, the content liquid may leak or scatter. For this reason, the plug used for the medical container is required to have a re-sealing property, that is, a performance of preventing the leakage of the content liquid and a liquid leakage resistance, in which the needle hole is re-closed after the needle is removed from the plug. .
From the viewpoint of resealability and liquid leakage resistance, rubber materials such as isoprene rubber, butadiene rubber, butyl rubber, and blends thereof have been conventionally used as materials for plugs for medical containers.
However, when the rubber material is used, at least a filler, a softening agent, an additive such as a vulcanizing agent is added to the rubber component and kneaded to obtain a rubber mixture, and the kneaded rubber mixture is plugged. It is necessary to produce a rubber material through a vulcanization step of supplying the rubber material to a mold for heating, heating and pressing. Since the manufacturing process of the rubber material is complicated and requires large-scale manufacturing equipment, there are problems such as high production cost.
In addition, the plug of the medical container using the rubber material is deteriorated due to oxidation of a double bond in the rubber component during the storage period of the medical container, and the deteriorated rubber component is contained in the chemical solution. Has the problem of eluting into

By the way, from the viewpoint of handleability and safety, the injection needle is being replaced with a plastic needle from a metal needle conventionally used widely.
Since such a plastic needle has lower rigidity than a metal needle, it is necessary to increase the needle diameter in order to obtain sufficient rigidity. However, when the diameter of the needle is increased, there is a problem that the resistance when the needle penetrates the plug of the medical container, that is, the resistance to needle stick increases.

In order to solve such a problem, various types of plugs using a thermoplastic elastomer have recently been proposed as plugs for medical containers.
For example, Patent Literature 1 discloses a medical rubber stopper formed by molding a resin composition containing a hydrogenated block copolymer, a softener for a hydrocarbon rubber, and a polyolefin resin.
Patent Document 2 discloses a medical resin composition comprising a hydrogenated block copolymer, a hydrogenated petroleum resin, a polyphenylene ether resin, a peroxide decomposable olefin resin, and a softener for a non-aromatic rubber. A medical plug is disclosed.

JP 2012-25944 A JP 2012-57162 A

However, the medical rubber stopper disclosed in Patent Literature 1 uses a sealed PET bottle, and performs a sealing test under a small amount of liquid. The sealability has not been verified. In addition, when the needle is pierced for a long time under the atmospheric pressure condition where the container using the plug is opened and the amount of liquid is large and the amount of liquid is large, the re-sealing property is still insufficient. It has the problem that it is not done.
Also, in the medical stopper disclosed in Patent Document 2, it is assumed that the state in which the needle is pierced in the stopper is short, and the state in which the needle is pierced for a long time is maintained. In the case where the needle is pulled out of, there is a problem that a sufficient re-sealing property is not obtained, and since the polyphenylene ether resin is used, the odor of the rubber mixture is strong, and the eluate increases. .
As described above, the conventionally proposed plug for a medical container using a thermoplastic elastomer has not yet obtained sufficient resealability, and in order to improve the resealability, the plug is required. It is necessary to increase the thickness of the outer plug or to reduce the internal volume of the outer plug portion to which the plug is loaded, thereby increasing the tightening force, that is, caulking, but in any case, the resistance at the time of needle removal and piercing becomes large. However, there is a problem that the injection needle cannot be stabbed well, and since the polyphenylene ether resin is used, there is a problem that the rubber mixture has a strong odor, and there is a problem that the eluate increases. I have.

  Therefore, in the present invention, in view of the above-described problems of the prior art, a thermoplastic elastomer composition, a plug, and a container having excellent resealability, low odor, and reduction of eluted substances have been achieved. The purpose is to provide.

The present inventors have conducted intensive studies to solve the above-described problems of the prior art, and as a result, a hydrogenated block copolymer having a predetermined structure, a polypropylene resin, a non-aromatic softener, and a surface treatment. The present inventors have found that a thermoplastic elastomer composition containing the above-mentioned inorganic filler, which is silica, at a predetermined ratio can solve the above-mentioned problems of the prior art, and have completed the present invention.
That is, the present invention is as follows.

[1]
100 parts by mass of a hydrogenated block copolymer (a),
10 to 50 parts by mass of a polypropylene resin (b),
75 to 200 parts by mass of a non-aromatic softener (d);
1 to 150 parts by mass of an inorganic filler (e),
A thermoplastic elastomer composition comprising:
The hydrogenated block copolymer (a) comprises a polymer block A1 mainly composed of at least one vinyl aromatic hydrocarbon compound monomer unit and a polymer block mainly composed of at least one conjugated diene compound monomer unit. And a hydrogenated hydrogenated block copolymer (a-1),
The hydrogenated block copolymer (a-1) has a weight average molecular weight of 100,000 to 550,000,
The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) is more than 20% by mass and 50% by mass or less;
A thermoplastic elastomer composition, wherein the inorganic filler (e) is surface-treated silica.
[2]
The hydrogenated block copolymer (a) is:
The hydrogenated block copolymer (a-1),
Hydrogenation comprising at least one polymer block A2 mainly composed of a vinyl aromatic hydrocarbon compound monomer unit and at least one polymer block B2 mainly composed of a conjugated diene compound monomer unit A hydrogenated block copolymer (a-2),
The hydrogenated block copolymer (a-2) has a weight average molecular weight of 120,000 to 230,000,
The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-2) is 7% by mass or more and 20% by mass or less,
The mass ratio ((a-1) / (a-2)) of the hydrogenated block copolymer (a-1) to the hydrogenated block copolymer (a-2) is 70/30 to 95/5. The thermoplastic elastomer composition according to the above [1].
[3]
The heat according to [2], wherein, in the hydrogenated block copolymer (a-2), the vinyl bond amount in the monomer unit of the conjugated diene compound before hydrogenation is 63 mol% to 95 mol%. Plastic elastomer composition.
[4]
The hydrogenated block copolymer (a-2) comprises at least two polymer blocks A2 mainly composed of vinyl aromatic hydrocarbon compound monomer units and at least two conjugated diene compound monomer units. And a main polymer block B2,
The at least one polymer block B2 is located at a terminal of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the terminal is determined by the hydrogenated block copolymer (a). The thermoplastic elastomer composition according to the above [2] or [3], wherein the content of the thermoplastic elastomer is 0.5 to 9% by mass in -2).
[5]
In the hydrogenated block copolymer (a-1), the vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit is 30 mol% to 60 mol%.
The thermoplastic elastomer composition according to any one of the above [1] to [4].
[6]
Shore A hardness is 55 or less, needle stick resistance is 4.0 kgf or less,
The thermoplastic elastomer composition according to any one of the above [1] to [5].
[7]
The inorganic filler (e) is
Surface-treated with a silane coupling agent,
The thermoplastic elastomer composition according to any one of the above [1] to [6].
[8]
The thermoplastic elastomer composition according to any one of [1] to [7], wherein the odor intensity according to the six-stage odor intensity display method is 3 or less.
[9]
A plug comprising the thermoplastic elastomer composition according to any one of the above [1] to [8].
[10]
A container comprising the plug according to the above [9].
[11]
A plug for medical use, comprising the thermoplastic elastomer composition according to any one of [1] to [8].
[12]
A container for medical use comprising the plug according to the above [11].

  According to the present invention, a thermoplastic elastomer composition, a plug, and a container having excellent resealability, low odor, and reduced eluate can be obtained.

(A) The schematic top view of an example of a plug is shown. (B) The schematic sectional drawing of an example of a plug is shown. (A) The schematic top view of an example of the state which attached the plug body to the jig is shown. (B) The schematic sectional drawing of an example of the state which attached the plug body to the jig is shown.

Hereinafter, embodiments for carrying out the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail.
The following embodiment is an example for describing the present invention, and does not limit the present invention to the following contents. The present invention can be implemented with various modifications within the scope of the gist.

(Thermoplastic elastomer composition)
The thermoplastic elastomer composition of the present embodiment,
100 parts by mass of a hydrogenated block copolymer (a),
10 to 50 parts by mass of a polypropylene resin (b),
75 to 200 parts by mass of a non-aromatic softener (d);
1 to 150 parts by mass of an inorganic filler (e),
, Including
The hydrogenated block copolymer (a) comprises a polymer block A1 mainly composed of at least one vinyl aromatic hydrocarbon compound monomer unit and a polymer block mainly composed of at least one conjugated diene compound monomer unit. And a hydrogenated hydrogenated block copolymer (a-1),
The hydrogenated block copolymer (a-1) has a weight average molecular weight of 100,000 to 550,000,
The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) is more than 20% by mass and 50% by mass or less;
A thermoplastic elastomer composition wherein the inorganic filler (e) is surface-treated silica.

The thermoplastic elastomer composition of the present embodiment has excellent resealability, low odor, and reduced eluate by having the above-described configuration.
Hereinafter, each component of the thermoplastic elastomer composition of the present embodiment will be described in detail.

(Hydrogenated block copolymer (a))
The hydrogenated block copolymer (a) contained in the thermoplastic elastomer of the present embodiment includes a hydrogenated block copolymer (a-1) described later.
<Hydrogenated block copolymer (a-1)>
The hydrogenated block copolymer (a-1) is mainly composed of a polymer block A1 mainly composed of at least one vinyl aromatic hydrocarbon compound monomer unit and at least one monomer unit of a conjugated diene compound. Is a hydrogenated block copolymer obtained by hydrogenating (hydrogenating) a block copolymer containing the polymer block B1.

  The polymer block A1 mainly composed of the vinyl aromatic hydrocarbon compound monomer units means that the content of the vinyl aromatic hydrocarbon compound monomer units in the polymer block A1 exceeds 50% by mass. However, from the viewpoint of the mechanical strength and the resiliency related to the resealability, that is, from the viewpoint of the performance that the needle hole is reclosed after the needle is pulled out from the stopper, it is preferably at least 60% by mass, more preferably at least 70% by mass. , More preferably 80% by mass or more, and even more preferably 90% by mass or more.

Similarly, the polymer block B1 mainly containing the conjugated diene compound monomer unit means that the content of the conjugated diene compound monomer unit in the polymer block B1 exceeds 50% by mass. From the viewpoint of the recoverability of the sealing property, it is preferably at least 60% by mass, more preferably at least 70% by mass, further preferably at least 80% by mass, and still more preferably at least 90% by mass.
In the present embodiment, the naming of each monomer unit constituting the block copolymer follows the naming of the monomer from which the monomer unit is derived. For example, “vinyl aromatic hydrocarbon compound monomer unit” means a structural unit of a polymer obtained by polymerizing a vinyl aromatic hydrocarbon compound as a monomer, and its structure is represented by a substituted vinyl group. Is a molecular structure in which two carbons of a substituted ethylene group derived from the above are binding sites.
Further, the “conjugated diene compound monomer unit” means a constituent unit of a polymer obtained by polymerizing a conjugated diene compound which is a monomer, and its structure is derived from the conjugated diene compound monomer. It is a molecular structure in which two carbons of an olefin are binding sites.

In this embodiment, the monomer that can be used as the vinyl aromatic hydrocarbon compound monomer unit in the polymer block A1 refers to a compound having a vinyl group and an aromatic ring.
Examples of the vinyl aromatic hydrocarbon compound monomer include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N, N-dimethyl-p- Aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene and the like can be mentioned. Among these, styrene, α-methylstyrene, and divinylbenzene are preferably used from the viewpoint of polymerizability. One of these vinyl aromatic hydrocarbon compound monomers may be used alone, or two or more thereof may be used.

The monomer which can be used as the conjugated diene compound monomer unit in the polymer block B1 is a diolefin having a pair of conjugated double bonds (two conjugated double bonds). .
Examples of the conjugated diene compound monomer include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, Examples thereof include 3-pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Among these, 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene) are preferably used from the viewpoint of polymerizability. One of these conjugated diene compound monomers may be used alone, or two or more thereof may be used.

The hydrogenated block copolymer (a-1) has, for example, but is not limited to, a structure represented by the following general formulas (1) to (7).
Furthermore, the hydrogenated block copolymer (a-1) may be a mixture containing a plurality of types of copolymers having the structures represented by the following general formulas (1) to (7) at an arbitrary ratio. .
(A1-B1) _n (1)
A1- (B1-A1) _n (2)
B1- (A1-B1) _n (3)
[(B1-A1) _n ] _m- Z (4)
[(A1-B1) _n ] _m- Z (5)
[(B1-A1) _n -B1] _m -Z (6)
[(A1-B1) _n -A1] _m -Z (7)

In the general formulas (1) to (7), A1 is a polymer block mainly composed of a vinyl aromatic hydrocarbon compound monomer unit, and B1 is a polymer block mainly composed of a conjugated diene compound monomer unit. It is. The boundary between the polymer block A1 and the polymer block B1 does not necessarily need to be clearly distinguished.
N is an integer of 1 or more, preferably an integer of 1 to 5.
m is an integer of 2 or more, preferably 2 to 11, more preferably 2 to 8.
Z represents a coupling agent residue. Here, the coupling residue refers to a plurality of copolymers of a conjugated diene compound monomer unit and a vinyl aromatic hydrocarbon compound monomer unit, which are defined as a portion between the polymer block A1 and the polymer block A1, The residue after coupling of the coupling agent used for coupling between the block B1 and the polymer block B1 or between the polymer block A1 and the polymer block B1 is meant. Examples of the coupling agent include, but are not limited to, dihalogen compounds and acid esters described below.

In the general formulas (1) to (7), the monomer units of the vinyl aromatic hydrocarbon compound in the polymer block A1 and the polymer block B1 may be uniformly distributed or tapered. Good.
Further, when the polymer block A1 and the polymer block B1 are a copolymer block of a vinyl aromatic hydrocarbon compound monomer unit and a conjugated diene compound monomer unit, the vinyl aromatic in the copolymer block may be used. There may be a plurality of groups of the hydrocarbon group monomer units uniformly distributed and a plurality of parts tapered. Further, a plurality of portions having different contents of vinyl aromatic hydrocarbon compound monomer units may coexist in the copolymer block portion.

The weight average molecular weight of the hydrogenated block copolymer (a-1) is from 100,000 to 550,000.
From the viewpoint of thermal deformation resistance, it is preferably at least 120,000, more preferably at least 140,000. Moreover, it is preferably 500,000 or less, more preferably 450,000 or less, further preferably 400,000 or less, still more preferably 350,000 or less, and still more preferably 300,000 or less. .
Further, it is preferably 120,000 to 350,000, and more preferably 140,000 to 300,000.
When the weight average molecular weight of the hydrogenated block copolymer (a-1) is 100,000 or more, the thermoplastic elastomer composition of the present embodiment tends to have a good resealability with respect to the resealability. . When the weight average molecular weight of the hydrogenated block copolymer (a-1) is 550,000 or less, good fluidity is obtained in the thermoplastic elastomer composition, and excellent moldability is obtained.

The molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer (a-1) is preferably 1.01 to 8.0, more preferably 1.01 to 6.0, and still more preferably 1.01 to 5. 0.0.
If the molecular weight distribution of the hydrogenated block copolymer (a-1) is within the above range, better mechanical strength tends to be obtained.
The shape of the molecular weight distribution curve of the hydrogenated block copolymer (a-1) measured by gel permeation chromatography (GPC) is not particularly limited, and may have a polymodal molecular weight distribution having two or more peaks. It may have a monomodal molecular weight distribution with one peak.
The weight average molecular weight (Mw) and molecular weight distribution [Mw / Mn; ratio of weight average molecular weight (Mw) to number average molecular weight (Mn)] of the hydrogenated block copolymer (a-1) are described in Examples described later. Based on the molecular weight of the peak of the chromatogram measured by gel permeation chromatography (GPC) according to the method described in (1), a calibration curve (prepared using the peak molecular weight of standard polystyrene) obtained from the measurement of commercially available standard polystyrene was used. Can be sought using.
The weight average molecular weight of the hydrogenated block copolymer (a-1) can be controlled in the above-mentioned numerical range by adjusting the amount of the polymerization initiator and the amount of the monomer.

  In addition, the number average molecular weight of the block chain of the polymer block A1 mainly composed of a vinyl aromatic hydrocarbon compound monomer unit is determined by using osmium tetroxide as a catalyst to convert the hydrogenated block copolymer (a-1) into t- By a method of oxidative decomposition with butyl hydroperoxide (a method described in IM KOLTHOFF, et al., J. Polym. Soi. 1, 429 (1946)), a vinyl aromatic hydrocarbon compound monomer unit is obtained. (Herein, a polymer component comprising a vinyl aromatic monomer unit having an average degree of polymerization of about 30 or less is excluded), and measured by GPC in the same manner as described above. be able to.

The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) is more than 20% by mass and 50% by mass or less.
From the viewpoint of the recoverability of the mechanical properties and the resealability, it should exceed 20% by mass, preferably 22% by mass or more, more preferably 24% by mass or more, and still more preferably 26% by mass or more. And still more preferably 28% by mass or more.
Further, from the viewpoint of flexibility, the content is 50% by mass or less, preferably 47% by mass or less, more preferably 44% by mass or less, still more preferably 41% by mass or less, and still more preferably 38% by mass or less.
In addition, from the viewpoint of a balance between recoverability and flexibility, the content is more preferably 26 to 44% by mass, still more preferably 26 to 41% by mass, still more preferably 28 to 41% by mass, and still more preferably. Is 28 to 38% by mass.

When the content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) exceeds 20% by mass, the strength of the thermoplastic elastomer composition of the present embodiment tends to be improved. When the content of the total vinyl aromatic hydrocarbon compound is 50% by mass or less, the flexibility of the thermoplastic elastomer composition of the present embodiment tends to be improved.
The content of the monomer units of the whole vinyl aromatic hydrocarbon compound is controlled in the above numerical range by adjusting the amount of the monomer added in the polymerization step of the hydrogenated block copolymer (a-1). It can be calculated by measuring the absorption intensity at 262 nm using an ultraviolet spectrophotometer according to the method described in Examples described later.

  The microstructure (ratio of cis and trans structures, vinyl bond amount) of the polymer block B1 in the hydrogenated block copolymer (a-1) can be arbitrarily controlled by using a polar compound or the like described later.

The vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit in the hydrogenated block copolymer (a-1) is preferably 30 mol% to 60 mol%, more preferably 31 to 57 mol%. %, More preferably 31 to 54 mol%, still more preferably 32 to 51 mol%, and still more preferably 32 to 45 mol%.
When the vinyl bond content before hydrogenation in the conjugated diene compound monomer unit is 30 mol% or more, the compatibility between the hydrogenated block copolymer (a-1) and the polypropylene-based resin (b) described later becomes insufficient. If the vinyl bond content before hydrogenation in the conjugated diene compound monomer unit is 60 mol% or less, the strength tends to be further improved.

  As described above, in the present embodiment, the content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) is more than 20% by mass and 50% by mass or less, Further, it is preferable that the vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit is 30 mol% to 60 mol%.

In the present embodiment, the amount of vinyl bond refers to, for example, the amount of conjugated diene monomer incorporated in butadiene in a 1,2-bond, 3,4-bond and 1,4-bond bonding mode before hydrogenation. It is a ratio of the total molar amount of the conjugated diene monomer unit incorporated by 1,2-bond and 3,4-bond to the total molar amount of the body unit.
In addition, after hydrogenation, 1,2-bond without hydrogen, 1,2-bond after hydrogenation, 3,4-bond without hydrogen, 3,4-bond after hydrogenation, hydrogen-free The 1,2-bond without hydrogenation and the 1,2-bond after hydrogenation with respect to the total molar amount of the conjugated diene monomer units incorporated in the 1,4-bond and 1,4-bond bonding modes after hydrogenation The ratio of the total molar amount of the conjugated diene monomer unit incorporated in the 1,2-bond, the 3,4-bond without hydrogenation, and the 3,4-bond after hydrogenation is determined based on the conjugated diene before hydrogenation. Equal to the amount of vinyl bonds in the monomer unit. Therefore, the amount of vinyl bonds in the conjugated diene monomer unit before hydrogenation can be measured by nuclear magnetic resonance spectroscopy (NMR) using the block copolymer after hydrogenation. It can be measured by the method described.

  The hydrogenation rate of the aliphatic double bond derived from the conjugated diene compound in the hydrogenated block copolymer (a-1) is preferably at least 50%, more preferably at least 60%, further preferably 70% or more. When the hydrogenation rate is 50% or more, a decrease in mechanical properties due to thermal deterioration (oxidative deterioration) tends to be more effectively suppressed. If the hydrogenation rate is 70% or more, more excellent weather resistance tends to be obtained. Although the upper limit of the hydrogenation rate is not particularly limited, it is preferably 100% or less, and more preferably 99% or less.

  Further, when the thermoplastic elastomer composition of the present embodiment is partially crosslinked using an organic peroxide (g) described later, the conjugate in the hydrogenated block copolymer (a-1) is preferably used from the viewpoint of heat resistance. The hydrogenation rate of the aliphatic double bond derived from the diene compound is preferably 50% or more, more preferably 60% or more, and from the viewpoint of processability and crosslinking reactivity, 90% or less is preferable, and 85% or less. Is more preferred.

  The hydrogenation rate of the aromatic double bond based on the vinyl aromatic hydrocarbon compound monomer unit in the hydrogenated block copolymer (a-1) is not particularly limited, but is preferably from the viewpoint of strength and heat resistance. Is 50% or less, more preferably 30% or less, and further preferably 20% or less.

<Hydrogenated block copolymer (a-2)>
The hydrogenated block copolymer (a) contained in the thermoplastic elastomer composition of the present embodiment includes the hydrogenated block copolymer (a-1) and the hydrogenated block copolymer (a-1). May contain a different hydrogenated block copolymer (a-2).
The hydrogenated block copolymer (a-2) is mainly composed of a polymer block A2 mainly composed of at least one vinyl aromatic hydrocarbon compound monomer unit and at least one conjugated diene compound monomer unit. And a hydrogenated block copolymer obtained by hydrogenating a block copolymer containing the polymer block B2 having a weight average molecular weight of 120,000 to 230,000. Further, the content of all the vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-2) is from 7% by mass to 20% by mass.
When the thermoplastic elastomer composition of the present embodiment is used as a plug for the purpose of piercing a needle, the flexibility of the thermoplastic elastomer composition affects the resistance to needle piercing, but excessively decreases the needle piercing resistance. If the flexibility is improved, the needle may fall out of the stopper during use, and the force for holding the needle (needle holding property) tends to decrease.
Although the flexibility of the thermoplastic elastomer composition is correlated with various factors, the smaller the amount of the vinyl aromatic hydrocarbon compound in the hydrogenated block copolymer, for example, the smaller the amount of styrene, the more the component (a-2) becomes. The larger the amount, the smaller the amount of the polypropylene resin (b), the amount of the inorganic filler (e), and the amount of the inorganic porous adsorbent (f) in the thermoplastic elastomer composition, and the larger the amount of the non-aromatic softener (d), the more the thermoplastic resin. The flexibility of the elastomer composition, that is, the softness, tends to be improved.
From the viewpoint of improving the balance between needle stick resistance and resealability, the hydrogenated block copolymer (a) is obtained by combining the hydrogenated block copolymer (a-1) and the hydrogenated block copolymer (a-2). Preferably, the mixture is a mixture containing In this case, the mass ratio ((a-1) / (a-2)) of the hydrogenated block copolymer (a-1) to the hydrogenated block copolymer (a-2) is 70/30 to 95/5. It is preferred that When the mass ratio of the hydrogenated block copolymer (a-1) to the hydrogenated block copolymer (a-2) is within the above range, the balance between needle stick resistance and resealability can be improved. From the same viewpoint, the mass ratio is more preferably from 75/25 to 95/5, and still more preferably from 80/20 to 95/5.

  In the hydrogenated block copolymer (a-2), the polymer block A2 mainly composed of a vinyl aromatic hydrocarbon compound monomer unit is defined as a vinyl aromatic hydrocarbon compound monomer unit in the polymer block A2. Means more than 50% by mass, preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more. is there.

  Similarly, in the hydrogenated block copolymer (a-2), the content of the conjugated diene compound monomer unit in the polymer block B2 refers to the content of the conjugated diene compound monomer unit in the polymer block B2. Is more than 50% by mass, preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more.

  The monomer that can be used as the vinyl aromatic hydrocarbon compound monomer unit in the polymer block A2 refers to a compound having a vinyl group and an aromatic ring. Examples of the vinyl aromatic hydrocarbon compound monomer include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N, N-dimethyl-p- Aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene and the like can be mentioned. Among these, styrene, α-methylstyrene, and divinylbenzene are preferably used from the viewpoint of polymerizability. One of these vinyl aromatic hydrocarbon compound monomers may be used alone, or two or more thereof may be used.

The monomer that can be used as the conjugated diene compound monomer unit in the polymer block B2 is a diolefin having a pair of conjugated double bonds (two conjugated double bonds). .
Examples of the conjugated diene compound monomer include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, Examples thereof include 3-pentadiene, 2-methyl-1,3-pentadiene, and 1,3-hexadiene. Among these, 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene) are preferably used from the viewpoint of polymerizability. One of these conjugated diene compound monomers may be used alone, or two or more thereof may be used.

The hydrogenated block copolymer (a-2) is not limited to the following, but has, for example, a structure represented by the following general formulas (8) to (14). Further, the hydrogenated block copolymer (a-2) may be a mixture containing a plurality of types of structures represented by the following general formulas (8) to (14) at an arbitrary ratio.
(A2-B2) _n (8)
A2- (B2-A2) _n (9)
B2- (A2-B2) _n (10)
[(B2-A2) _n ] _m -Z (11)
[(A2-B2) _n ] _m- Z (12)
[(B2-A2) _n -B2] _m -Z (13)
[(A2-B2) _n -A2] _m -Z (14)

In the general formulas (8) to (14), A2 is a polymer block mainly composed of a vinyl aromatic hydrocarbon compound monomer unit, and B2 is a polymer block mainly composed of a conjugated diene compound monomer unit. It is. The boundary between the polymer block A2 and the polymer block B2 does not necessarily need to be clearly distinguished.
N is an integer of 1 or more, preferably an integer of 1 to 5.
m is an integer of 2 or more, preferably 2 to 11, more preferably 2 to 8.
Z represents a coupling agent residue. Here, the coupling residue refers to a plurality of copolymers of a conjugated diene compound monomer unit and a vinyl aromatic hydrocarbon compound monomer unit, between the polymer block A2 and the polymer block A2, It means the residue after the coupling of the coupling agent used for coupling between the block B2 and the polymer block B2 or between the polymer block A2 and the polymer block B2. Examples of the coupling agent include, but are not limited to, dihalogen compounds and acid esters described below.

  In the general formulas (8) to (14), the vinyl aromatic hydrocarbon compound monomer units in the polymer block A2 and the polymer block B2 may be uniformly distributed or tapered. Good. When the polymer block A2 and the polymer block B2 are a copolymer block of a vinyl aromatic hydrocarbon compound monomer unit and a conjugated diene compound monomer unit, the vinyl aromatic in the copolymer block may be used. There may be a plurality of groups of the group-containing hydrocarbon compound monomer uniformly distributed and / or a plurality of parts distributed in a tapered shape. Further, a plurality of portions having different contents of the vinyl aromatic hydrocarbon compound monomer unit may coexist in the copolymer block portion.

When the hydrogenated block copolymer (a-2) has at least two polymer blocks A2 and at least two polymer blocks B2, at least one polymer block B2 contains The content of the polymer block B2 at the terminal of the addition block copolymer (a-2) and at the terminal is 0.5 to 9% by mass in the hydrogenated block copolymer (a-2). Preferably, it is 1 to 7% by mass, more preferably 3 to 7% by mass.
At least one polymer block B2 is at the terminal of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the terminal is equal to the content of the hydrogenated block copolymer (a-2). ), The thermoplastic elastomer of this embodiment tends to be more excellent in flexibility by being 0.5 to 9% by mass. The content of the polymer block B2 at the terminal can be calculated by subtracting the mass of the conjugated diene polymerized at the terminal from the mass of all the monomers used in the polymerization reaction.
In the hydrogenated block copolymer (a-2), at least one polymer block B2 is at the terminal, and in order to keep the content of the polymer block B2 at the terminal within the above numerical range, the hydrogenated block In the polymerization step of the copolymer (a-2), a method of adjusting the timing and amount of addition of the monomer is effective.

The weight average molecular weight of the hydrogenated block copolymer (a-2) is from 120,000 to 230,000.
When the weight-average molecular weight of the hydrogenated block copolymer (a-2) is 120,000 or more, the thermoplastic elastomer composition of the present embodiment can have properties such as a small compression set such as C-set. That is, the recoverability is improved. When the weight average molecular weight of the hydrogenated block copolymer (a-2) is 230,000 or less, the resilience of the thermoplastic elastomer composition is improved, and the medical container using the thermoplastic elastomer composition of the present embodiment is used. In the plug for use, sufficient resealability and effect of improving needle stick resistance can be obtained. From the same viewpoint, the weight average molecular weight of the hydrogenated block copolymer (a-2) is preferably from 140,000 to 220,000, more preferably from 150,000 to 210,000, and still more preferably. 160,000-200,000.

  The molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer (a-2) is preferably from 1.01 to 8.0, more preferably from 1.01 to 6.0, and still more preferably 1 to 6.0. 0.01 to 5.0. If the molecular weight distribution is within the above range, the thermoplastic elastomer composition of the present embodiment tends to have better recoverability and mechanical strength. The Mw and Mn of the hydrogenated block copolymer (a-2) can also be measured by GPC.

  The shape of the molecular weight distribution curve of the hydrogenated block copolymer (a-2) is not particularly limited, and may have a polymodal molecular weight distribution having two or more peaks, or may have a single peak. It may have a modal molecular weight distribution.

  The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-2) is from 7% by mass to 20% by mass, preferably from 9% by mass to 18% by mass. Preferably it is 11 to 16 mass%. When the content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-2) is 7% by mass or more, the mechanical strength of the thermoplastic elastomer composition tends to be further improved. Yes, if the content of the total vinyl aromatic hydrocarbon compound is 20% by mass or less, the flexibility and recovery of the thermoplastic elastomer composition tend to be further improved, and the resealability tends to be further improved.

The vinyl bond amount in the conjugated diene compound monomer unit in the hydrogenated block copolymer (a-2) before hydrogenation is preferably 63 mol% to 95 mol%, more preferably 65 mol% to 90 mol%, More preferably, it is 67 mol% to 85 mol%.
When the vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit in the hydrogenated block copolymer (a-2) is 63 mol% or more, compatibility with the polypropylene resin (b) described later Of the thermoplastic elastomer of the present embodiment, and the resealability tends to be further improved. If the vinyl bond content before hydrogenation in the conjugated diene compound monomer unit is 95 mol% or less, the mechanical strength of the thermoplastic elastomer composition of the present embodiment is further improved, and the coring is further improved. There is a tendency.

  From the viewpoint described above, in the present embodiment, in the hydrogenated block copolymer (a-2), the content of all vinyl aromatic hydrocarbon compound monomer units is 7% by mass to 20% by mass, More preferably, the vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit is from 63 mol% to 95 mol%.

  The hydrogenation rate of the aliphatic double bond derived from the conjugated diene compound in the hydrogenated block copolymer (a-2) is preferably at least 80%, more preferably at least 90%. When the hydrogenation rate is 80% or more, it is possible to suppress deterioration in mechanical properties due to thermal deterioration, that is, oxidation deterioration. The upper limit of the hydrogenation rate is not particularly limited, but is preferably 100% or less, and more preferably 99% or less.

  The hydrogenation rate of the aromatic double bond based on the vinyl aromatic hydrocarbon compound monomer unit in the hydrogenated block copolymer (a-2) is not particularly limited, and is preferably from the viewpoint of strength and heat resistance. Is 50% or less, more preferably 30% or less, and still more preferably 20% or less.

  The method for producing the hydrogenated block copolymer (a) is not limited to the following. Examples thereof include JP-B-36-19286, JP-B-43-17979, JP-B-46-32415, and JP-B-49. JP-A-36957, JP-B-48-2423, JP-B-48-4106, JP-B-51-49567, and JP-A-59-166518.

The copolymer of the hydrogenated block copolymer (a) containing the conjugated diene compound monomer unit and the vinyl aromatic hydrocarbon compound monomer unit before hydrogenation is not limited to the following. It is obtained by a method of conducting anionic living polymerization using a polymerization initiator such as an organic alkali metal compound in a hydrogen solvent.
The hydrocarbon solvent is not particularly limited, and examples thereof include aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane; cyclohexane, cycloheptane, methylcycloheptane And alicyclic hydrocarbons such as benzene, toluene, xylene and ethylbenzene.

The polymerization initiator is not particularly limited, but generally, an organic alkali metal compound which is known to have anionic polymerization activity with respect to a conjugated diene compound monomer and a vinyl aromatic hydrocarbon compound monomer. Preferred are, for example, an aliphatic hydrocarbon alkali metal compound having 1 to 20 carbon atoms, an aromatic hydrocarbon alkali metal compound having 1 to 20 carbon atoms, and an organic amino alkali metal compound having 1 to 20 carbon atoms.
The alkali metal contained in the polymerization initiator is not limited to the following, but examples include lithium, sodium, and potassium. In addition, one kind or two or more kinds of alkali metals may be contained in one molecule. Specifically, although not limited to the following, for example, n-propyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, n-pentyl lithium, n-hexyl lithium, benzyl lithium, phenyl lithium, tolyl Examples of the reaction product include reaction products of lithium and diisopropenylbenzene with sec-butyllithium, and reaction products of divinylbenzene with sec-butyllithium and a small amount of 1,3-butadiene.
Furthermore, 1- (t-butoxy) propyllithium disclosed in U.S. Pat. No. 5,708,092 and a lithium compound having one or several molecules of isoprene monomer inserted to improve its solubility; Siloxy-containing alkyllithiums such as 1- (t-butyldimethylsiloxy) hexyllithium disclosed in U.S. Pat. No. 2,241,239; Amino-containing alkyl disclosed in U.S. Pat. No. 5,527,753 Amino lithiums such as alkyl lithium, lithium diisopropylamide and lithium hexamethyldisilazide can also be used.

When an organic alkali metal compound is used as a polymerization initiator, when a conjugated diene compound monomer and a vinyl aromatic hydrocarbon compound monomer are copolymerized, a vinyl bond caused by the conjugated diene compound monomer incorporated into the copolymer In order to adjust the content of (1,2-bond or 3,4-bond) or to adjust the random copolymerizability of the conjugated diene compound monomer and the vinyl aromatic hydrocarbon compound monomer, , A tertiary amine compound, an ether compound, and a metal alcoholate compound.
As the modifier, only one type may be used alone, or two or more types may be used in combination.

As the tertiary amine compound of the regulator, a compound represented by the general formula R1R2R3N can be applied.
Here, in the above general formula, R1, R2 and R3 represent a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having a tertiary amino group.
Examples of the tertiary amine compound include, but are not limited to, trimethylamine, triethylamine, tributylamine, N, N-dimethylaniline, N-ethylpiperidine, N-methylpyrrolidine, N, N, N ′. , N'-tetramethylethylenediamine, N, N, N ', N'-tetraethylethylenediamine, 1,2-dipiperidinoethane, trimethylaminoethylpiperazine, N, N, N', N ", N" -penta Methyl ethylene triamine, N, N'-dioctyl-p-phenylenediamine and the like can be mentioned.

As the ether compound of the adjusting agent, a linear ether compound, a cyclic ether compound and the like can be applied.
Examples of the linear ether compound include, but are not limited to, dimethyl ether, diethyl ether, diphenyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, dialkyl ether compounds of ethylene glycol such as ethylene glycol dibutyl ether, Examples thereof include dialkyl ether compounds of diethylene glycol such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol dibutyl ether.
Examples of the cyclic ether compound include, but are not limited to, tetrahydrofuran, dioxane, 2,5-dimethyloxolane, 2,2,5,5-tetramethyloxolane, 2,2-bis (2 -Oxolanyl) propane, alkyl ethers of furfuryl alcohol and the like.

  Examples of the metal alcoholate compound of the regulator include, but are not limited to, sodium-t-pentoxide, sodium-t-butoxide, potassium-t-pentoxide, potassium-t-butoxide and the like.

The method of copolymerizing a conjugated diene compound monomer and a vinyl aromatic hydrocarbon compound monomer with an organic alkali metal compound as a polymerization initiator is not particularly limited, and may be either batch polymerization or continuous polymerization. Alternatively, a combination thereof may be used. From the viewpoint of adjusting the molecular weight distribution to a preferable range, a batch polymerization method is preferable.
The polymerization temperature is not particularly limited, but is usually 0 to 180 ° C, preferably 30 to 150 ° C. The time required for the polymerization varies depending on the conditions, but is usually within 48 hours, preferably 0.1 to 10 hours.
The polymerization is preferably performed in an atmosphere of an inert gas such as nitrogen gas. The polymerization pressure is not particularly limited, as long as the polymerization is performed at a pressure sufficient to maintain the monomer and the solvent in the liquid phase in the above-mentioned polymerization temperature range.

  Further, a coupling reaction may be performed by adding a necessary amount of a coupling agent having two or more functional groups at the end of the polymerization. The coupling agent having two or more functional groups is not particularly limited, and a known agent can be used. Examples of the bifunctional group coupling agent include, but are not limited to, dihalogen compounds such as dimethyldichlorosilane and dimethyldibromosilane; methyl benzoate, ethyl benzoate, phenyl benzoate, phthalates, and the like. Acid esters and the like.

Examples of the polyfunctional coupling agent having three or more functional groups include, but are not limited to, polyhydric epoxy compounds such as trihydric or higher polyalcohols, epoxidized soybean oil, diglycidyl bisphenol A, and a compound represented by the general formula R ¹ _{( 4-n) a} silicon halide compound represented by SiX _n and a tin halide compound.
Here, in the general formula, R ¹ represents a hydrocarbon group having 1 to 20 carbon atoms, X represents a halogen, and n represents an integer of 3 or 4.

  Examples of the silicon halide compound include, but are not limited to, methylsilyl trichloride, t-butylsilyl trichloride, silicon tetrachloride, and bromides thereof.

  Examples of the tin halide compound include, but are not limited to, polyvalent halogen compounds such as methyltin trichloride, t-butyltin trichloride, and tin tetrachloride. Further, dimethyl carbonate, diethyl carbonate and the like can be used.

The hydrogenation catalyst used for producing the hydrogenated block copolymer is not particularly limited. For example, JP-B-42-8704, JP-B-43-6636, JP-B-63-4841, The hydrogenation catalyst described in Japanese Patent Publication No. 37970/1993, Japanese Patent Publication No. 1-53851, and Japanese Patent Publication No. 2-9041 can be used.
Preferred hydrogenation catalysts include a titanocene compound and a mixture of the titanocene compound and a reducing organometallic compound.
The titanocene compound is not particularly limited, and examples thereof include compounds described in JP-A-8-109219. Specifically, at least a ligand having a substituted or unsubstituted cyclopentadienyl structure, an indenyl structure, and a fluorenyl structure, such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. Compounds having at least one compound are exemplified.
Examples of the reducing organic metal compound include, but are not limited to, organic alkali metal compounds such as organic lithium, organic magnesium compounds, organic aluminum compounds, organic boron compounds, and organic zinc compounds.

As the method of the hydrogenation reaction, a known method can be applied, and the reaction temperature of the hydrogenation reaction is generally 0 to 200 ° C, preferably 30 to 150 ° C.
The pressure of hydrogen used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, and further preferably 0.3 to 5 MPa.
The reaction time of the hydrogenation reaction is usually 3 minutes to 10 hours, preferably 10 minutes to 5 hours.
The hydrogenation reaction can be used in any of a batch process, a continuous process, and a combination thereof.

Catalyst residues may be removed from the reaction solution after the hydrogenation reaction, if necessary.
The method of separating the hydrogenated block copolymer and the solvent is not limited to the following, for example, a solution of the hydrogenated block copolymer, a poor solvent for the hydrogenated block copolymer such as acetone or alcohol. A method of recovering by precipitating and recovering the hydrogenated block copolymer by adding a polar solvent, or by pouring a solution of the hydrogenated block copolymer into boiling water with stirring and removing the solvent by steam stripping to recover the solution. And a method in which the solvent is distilled off by directly heating the solution of the hydrogenated block copolymer.

An antioxidant may be added to the reaction solution for producing the hydrogenated block copolymer (a).
Examples of the antioxidant include, but are not limited to, phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and amine-based antioxidants.
Specifically, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3- (4'-hydroxy-3 ', 5'-di-t-butyl-phenyl) propionate, tetrakis- [Methylene-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate] methane], tris- (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 4,4'-butylidene-bis- (3-methyl-6-t-butylphenol), 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy {-1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxy) Fe Nyl) propionate], 1,6-hexanediol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) 1,3,5-triazine, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N'-hexamethylenebis (3,5-di-t-butyl-4 -Hydroxy-hydrocinnamamide), 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3 5-Di-t-butyl-4-hydroxybenzyl) benzene, a mixture of calcium bis (3,5-di-t-butyl-4-hydroxybenzylphosphonate) calcium and polyethylene wax (50%), octylated diphenylamine, 2,4-bis [(octylthio) methyl] -o-cresol, isooctyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, butyric acid, 3,3-bis (3-t -Butyl-4-hydroxyphenyl) ethylene ester, 1,1,3-tris- (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-tris (4-t-butyl -3-Hydroxy-2,6-dimethylbenzyl) isocyanurate, 2-tert-butyl-6- (3'-tert-butyl-5'-methyl-2'-hydro Cibenzyl) -4-methylphenyl-acrylate, 2- [1- (2-hydroxy-3,5-di-t-pentylphenyl) -ethyl] -4,6-di-t-pentylphenyl acrylate, and the like. Can be

(Polypropylene resin (b))
The thermoplastic elastomer composition of the present embodiment contains a polypropylene resin (b).
Examples of the polypropylene-based resin (b) include, but are not limited to, a propylene homopolymer, or a block copolymer of propylene and an olefin other than propylene, preferably an α-olefin having 2 to 20 carbon atoms. Alternatively, a random copolymer or a blend thereof may be used.
Examples of the α-olefin having 2 to 20 carbon atoms include, but are not limited to, ethylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and the like. , Preferably an α-olefin having 2 to 8 carbon atoms, more preferably ethylene, 1-butene, 1-hexene and 4-methyl-1-pentene.
The polypropylene resin may be used alone or in combination of two or more.

  The polypropylene resin (b) preferably has a melt flow rate value (MFR) of 0.1 to 50 g / 10 min, more preferably 0.5 to 50 g, at a temperature of 230 ° C. and a load of 2.16 kg. It is 45 g / 10 min, more preferably 1.0 to 40 g / 10 min. If the MFR is within the above range, the moldability tends to be further improved.

The method for producing the polypropylene-based resin (b) is not limited to the following. Manufacturing method.
The titanium-containing solid transition metal component used in the Ziegler-Natta type catalyst is not limited to the following. Titanium chloride is exemplified, and the organometallic component is not limited to the following, but includes, for example, an aluminum compound.

The polymerization method for producing the polypropylene-based resin (b) is not limited to the following, but includes, for example, a slurry polymerization method, a gas phase polymerization method, a bulk polymerization method, a solution polymerization method, and a multistage polymerization method combining these. And legal methods.
In these polymerization methods, only propylene is polymerized when a propylene homopolymer is obtained, and propylene and a monomer other than propylene are polymerized when a copolymer is obtained.

In the thermoplastic elastomer composition of the present embodiment, the content of the polypropylene resin (b) is 10 to 50 parts by mass, preferably 13 to 50 parts by mass with respect to 100 parts by mass of the hydrogenated block copolymer (a). It is 50 parts by mass, more preferably 15 to 45 parts by mass.
When the content of the polypropylene-based resin (b) is 10 parts by mass or more, good fluidity is obtained in the thermoplastic elastomer composition of the present embodiment, and excellent moldability and coring properties are obtained. When the content of the polypropylene resin (b) is 50 parts by mass or less, in the thermoplastic elastomer composition of the present embodiment, good rebound resilience and flexibility are obtained, and excellent needle stick resistance is obtained.

(Polyphenylene ether resin (c))
The thermoplastic elastomer of the present embodiment may contain a polyphenylene ether resin (c).
The polyphenylene ether resin (c) is preferably a homopolymer and / or a copolymer having a repeating structural unit represented by the following general formula (I).

In the general formula (I), O represents an oxygen atom.
R ^{2 to} R ⁵ are each independently hydrogen, halogen, a primary or secondary C1 to C7 alkyl group, phenyl group, C1 to C7 haloalkyl group, C1 to C7 aminoalkyl group, C1 to C7 hydrocarbyl. A roxy group or a halohydrocarbyloxy group, wherein at least two carbon atoms separate a halogen atom and an oxygen atom.

  The method for producing the polyphenylene ether resin (c) is not particularly limited, and a known method can be used. For example, U.S. Pat. No. 3,306,874, U.S. Pat. No. 3,306,875, U.S. Pat. No. 3,257,357, U.S. Pat. No. 3,257,358, JP-A-50-51197, and JP-B-52-17880. And the production method described in JP-B-63-152628.

Examples of the polyphenylene ether resin (c) include, but are not limited to, poly (2,6-dimethyl-1,4-phenylene ether) and poly (2-methyl-6-ethyl-1,4-phenylene ether). And homopolymers such as poly (2-methyl-6-phenyl-1,4-phenylene ether) and poly (2,6-dichloro-1,4-phenylene ether), and 2,6-dimethylphenol and other Copolymers with phenols (for example, copolymers with 2,3,6-trimethylphenol and copolymers with 2-methyl-6-butylphenol as described in JP-B-52-17880) And polyphenylene ether copolymers such as
Among them, poly (2,6-dimethyl-1,4-phenylene ether), copolymerization of 2,6-dimethylphenol and 2,3,6-trimethylphenol, from the viewpoint of industrial productivity and heat resistance performance. Coalescence, or mixtures thereof, are preferred.

Further, the polyphenylene ether resin (c) may be a modified polyphenylene ether resin that is wholly or partially modified.
Here, the modified polyphenylene ether resin refers to at least one carbon-carbon double bond or triple bond and at least one carboxylic acid group, acid anhydride group, amino group, hydroxyl group, or glycidyl group in the molecular structure. Refers to a polyphenylene ether resin modified with at least one modification compound.

Examples of the modified compound having at least one carbon-carbon double bond and a carboxylic acid group or an acid anhydride group in the molecular structure include, but are not limited to, maleic acid, fumaric acid, chloromaleic acid, and cis-maleic acid. And 4-cyclohexene-1,2-dicarboxylic acid and acid anhydrides thereof.
Among these, fumaric acid, maleic acid, and maleic anhydride are preferred from the viewpoint of compatibility between the hydrogenated block copolymer (a) and the polyphenylene ether resin (c), and more preferred are fumaric acid and maleic anhydride. Is an acid.
Further, compounds in which one or two of the two carboxyl groups of these unsaturated dicarboxylic acids are esters can also be used.

  Modification compounds having at least one carbon-carbon double bond in the molecular structure, and a glycidyl group are not limited to, but include, for example, allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, epoxidized natural fats and the like. No. Of these, glycidyl acrylate and glycidyl methacrylate are preferred.

Examples of the modified compound having at least one carbon-carbon double bond and a hydroxyl group in the molecular structure include, but are not limited to, allyl alcohol, 4-penten-1-ol, 1,4-pentadiene-3 - (n is a positive integer) the formula C _n H _2n-3 OH such as all-unsaturated alcohol represented by the general formula C _n H _2n-5 OH, is _{C n H 2n-7 OH (} n positive Unsaturated alcohols represented by an integer).

  Each of the above various modifying compounds may be used alone or in combination of two or more.

  The addition rate of the modified compound of the modified polyphenylene ether resin (c) is preferably 0.01 to 5% by mass, and more preferably 0.1 to 3% by mass. The unreacted modified compound and / or polymer of the modified compound may remain in the modified polyphenylene ether resin (c) as long as the amount is less than 1% by mass.

The reduced viscosity ηsp / C (0.5 g / dL, chloroform solution, measured at 30 ° C.) of the polyphenylene ether resin (c) is preferably in the range of 0.15 to 0.70 dL / g, and 0.20 to 0. It is more preferably in the range of 0.60 dL / g, and more preferably in the range of 0.25 to 0.50 dL / g.
When the reduced viscosity of the polyphenylene ether resin (c) is 0.15 dL / g or more, in the thermoplastic elastomer composition of the present embodiment, good recoverability tends to be obtained, and 0.70 dL / g or less. If so, excellent workability tends to be obtained.
The reduced viscosity of the polyphenylene ether resin (c) can be controlled in the above numerical range by adjusting the type of catalyst, the polymerization time, and the polymerization temperature in the process for producing the polyphenylene ether resin (c).

In the present embodiment, two or more kinds of polyphenylene ether resins having different reduced viscosities may be blended and used as a polyphenylene ether resin (c) as a whole. In this case, the reduced viscosity of the mixture after mixing a plurality of polyphenylene ether resins is preferably in the range of 0.15 to 0.70 dL / g, and the reduced viscosity of each polyphenylene ether resin is 0.15 dL / g. It may not be in the range of 0.70 dL / g.
The reduced viscosity of the polyphenylene ether resin (c) can be measured by a method described in Examples described later.

  The number average molecular weight Mn of the polyphenylene ether resin (c) is preferably from 1,000 to 50,000, more preferably from 1,500 to 50,000, and still more preferably from 1,500 to 30,000. When the number average molecular weight of the polyphenylene ether resin (c) is within the above range, a thermoplastic elastomer composition having more excellent recoverability tends to be obtained.

  In addition, the number average molecular weight of the polyphenylene ether resin (c) was calculated from the standard molecular weight of a commercially available standard polystyrene based on the molecular weight of the peak of the chromatogram measured by GPC, similarly to the above-mentioned hydrogenated block copolymer (a). It can be determined using the determined calibration curve (created using the peak molecular weight of standard polystyrene).

As the polyphenylene ether resin (c), only one kind may be used alone, or a resin modified by blending with a resin such as a polystyrene-based resin or a polypropylene-based resin for improving processability may be used. Is also good.
Examples of the polystyrene resin include, but are not limited to, general-purpose polystyrene (GPPS), impact-resistant polystyrene (HIPS) reinforced with a rubber component, and a styrene-butadiene copolymer, which is used in the present embodiment. Hydrogenated styrene-butadiene copolymer other than hydrogenated block copolymer (a), styrene-maleic anhydride copolymer, styrene-acrylonitrile copolymer, styrene-acrylonitrile-butadiene copolymer, styrene-methyl methacrylate And copolymers. These copolymers may be random copolymers or block copolymers.
Examples of the polypropylene resin include, but are not limited to, a block copolymer or a random copolymer of propylene and an olefin other than propylene, preferably an α-olefin having 2 to 20 carbon atoms, or Mention may be made of blends thereof.

In the thermoplastic elastomer composition of the present embodiment, the content of the polyphenylene ether resin (c) is preferably 5 to 100 parts by mass based on 100 parts by mass of the hydrogenated block copolymer (a). It is more preferably 10 to 90 parts by mass, further preferably 20 to 85 parts by mass, and still more preferably 30 to 85 parts by mass.
When the content of the polyphenylene ether resin (c) is 5 parts by mass or more, sufficient recoverability and resilience can be obtained. When the content of the polyphenylene ether resin (c) is 100 parts by mass or less, the moldability of the thermoplastic elastomer composition tends to be good.
From the viewpoint of reducing the odor, the polyphenylene ether resin (c) does not contain, or the content is preferably small, the content is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and 1 part by mass or less. Is still more preferable, and it is even more preferable that it is not contained.
Even when the polyphenylene ether resin (c) is contained, the odor can be reduced by using the inorganic porous adsorbent (f) described below in combination. In this case, the content exceeds 10 parts by mass. Even if the amount is small, a thermoplastic elastomer composition having a low odor can be obtained. However, the filler that has not been subjected to surface treatment may have low compatibility with the resin, and the presence of the inorganic porous adsorbent (f) that has not been subjected to surface treatment may deteriorate the liquid leakage resistance. Therefore, in order to obtain a thermoplastic elastomer composition for a stopper having a small odor and a small liquid leakage, the content of the polyphenylene ether resin (c) is smaller and the inorganic porous adsorbent (f) having no surface treatment is used. It is preferable that the addition amount is also smaller.

(Non-aromatic softener (d))
The thermoplastic elastomer composition of the present embodiment contains a non-aromatic softener (d).
By using a non-aromatic softening agent, a thermoplastic elastomer composition having good color tone and suitable for food and medical use in terms of hygiene and safety tends to be easily obtained.
In addition, the aromatic softener enters the aromatic vinyl block and tends to deteriorate the heat resistance of the thermoplastic elastomer composition.However, by using a non-aromatic softener, from the viewpoint of heat resistance. Good.
The non-aromatic softener (d) is not particularly limited as long as it does not exhibit aromaticity and can soften the hydrogenated block copolymer. When the hydrogenated block copolymer is "softened", it is assumed that the softening agent does not break the aromatic vinyl block of the hydrogenated block copolymer and is taken into the conjugated diene block to be in a compatible state. Examples of the softening agent include, but are not limited to, paraffinic oil, naphthenic oil, paraffin wax, liquid paraffin, white mineral oil, and vegetable softening agent. Among these, a paraffinic oil, a liquid paraffin, and a white mineral oil are preferable from the viewpoint of low-temperature characteristics and elution resistance of a plug for a medical container containing the thermoplastic elastomer composition of the present embodiment.

The kinematic viscosity at 40 ° C. of the non-aromatic softener (d) is preferably 500 mm ² / sec or less. The lower limit of the kinematic viscosity at 40 ° C. of the non-aromatic softener (d) is not particularly limited, but is preferably 10 mm ² / sec or more.
When the kinematic viscosity at 40 ° C. of the non-aromatic softener (d) is 500 mm ² / sec or less, the flowability of the thermoplastic elastomer composition of the present embodiment is further improved, and the moldability tends to be further improved. It is in.
The kinematic viscosity of the non-aromatic softener (d) can be measured using a glass capillary viscometer.

As the non-aromatic softener (d), those containing a non-aromatic softener (d-1) having a kinematic viscosity at 40 ° C. in the range of 300 to 400 mm ² / sec can be suitably used.
If the non-aromatic softener (d) contains the non-aromatic softener (d-1) having a kinematic viscosity at 40 ° C. within the above range, the thermoplastic elastomer composition of the present embodiment is The non-aromatic softener-retaining property, that is, oil-retaining property is good, and the balance between resilience and rebound resilience tends to be improved.

Further, as the non-aromatic softener (d), those containing a non-aromatic softener (d-2) having a kinematic viscosity at 40 ° C. of 100 mm ² / sec or less can be suitably used.
As long as the non-aromatic softener (d) contains a non-aromatic middle agent (d-2) having a kinematic viscosity at 40 ° C. of 100 mm ² / sec or less, good oil retention was maintained. As it is, there is a tendency that a thermoplastic elastomer composition having more excellent flexibility and moldability is obtained.

Further, the non-aromatic softener (d) may be a combination of two or more non-aromatic softeners having different kinematic viscosities at 40 ° C.
For example, the non-aromatic softener (d-1) and the non-aromatic softener (d-2) can be used in combination.
By combining the non-aromatic softener (d-1) and the non-aromatic softener (d-2), the retention of the non-aromatic softener can be improved, and the flexibility and recovery properties can be improved. The balance between rebound resilience and moldability tends to be further improved.

When the non-aromatic softener (d-1) and the non-aromatic softener (d-2) are used in combination, the non-aromatic softener (d-1) and the non-aromatic softener (d- The mass ratio ((d-1) / (d-2)) of 2) is preferably from 30/70 to 60/40, more preferably from 35/75 to 60/40, and from 40/60 to 40/60. More preferably, it is 60/40.
When (d-1) / (d-2) is in the range of 30/70 to 60/40, the balance of flexibility, resilience, rebound resilience, and moldability tends to be further improved.

In the thermoplastic elastomer composition of the present embodiment, the content of the non-aromatic softener (d) is 75 to 200 parts by mass with respect to 100 parts by mass of the hydrogenated block copolymer (a), and is preferably 95 to 190 parts by mass, more preferably 115 to 180 parts by mass.
When the content of the non-aromatic softening agent (d) is within the above range, a thermoplastic elastomer which can further improve the retention of the non-aromatic softening agent (d) and is more excellent in moldability and recoverability Compositions tend to be obtained.

When two or more non-aromatic softeners having different kinematic viscosities at 40 ° C. are combined, the total content of the entire non-aromatic softener (d), for example, the non-aromatic softener (d-1) ) And the non-aromatic softener (d-2) are 75 to 200 parts by mass, preferably 95 to 190 parts by mass, based on 100 parts by mass of the hydrogenated block copolymer (a). More preferably, it is 115 to 180 parts by mass.
If the total content of the entire non-aromatic softener (d) is within the above range, the properties of both of the two or more non-aromatic softeners to be combined tend to be exhibited well.
In the present embodiment, the non-aromatic softener (d) has a kinematic viscosity at 40 ° C of 300 to 400 mm ² / sec, and a non-aromatic softener (d-1) at 40 ° C. It is a mixture of the non-aromatic softener (d-2) of 100 mm ² / sec or less, and the mass ratio of the non-aromatic softener (d-1) to the non-aromatic softener (d-2) ( (D-1) / (d-2)) is 30 / 70-60 / 40, and the total content of the non-aromatic softener (d-1) and the non-aromatic softener (d-2) Is more preferably 100 to 200 parts by mass with respect to 100 parts by mass of the hydrogenated block copolymer (a).

(Surface-treated inorganic filler (e))
The thermoplastic elastomer composition of the present embodiment contains surface-treated silica as the inorganic filler (e) from the viewpoint of needle retention.

In the thermoplastic elastomer composition of the present embodiment, as the inorganic filler (e), surface-treated silica is used, and the thermoplastic elastomer composition contains other inorganic fillers in addition to the silica. Is also good.
As other inorganic fillers, for example, may be silica not surface-treated, surface-treated, or talc, calcium carbonate, calcium oxide, zinc carbonate, wollastonite, zeolite, wollastonite, which is not surface-treated or surface-treated. Alumina, clay, titanium oxide, magnesium hydroxide, magnesium oxide, sodium silicate, calcium silicate, magnesium silicate, sodium aluminate, calcium aluminate, sodium aluminosilicate, zinc oxide, potassium titanate, hydrotalcite, sulfuric acid Barium, titanium black or the like, or carbon black such as furnace black, thermal black or acetylene black may be used.
As other inorganic fillers, when surface-treated inorganic fillers are added, the interfacial adhesion between the hydrogenated block copolymer and the polypropylene resin is good, interfacial peeling is unlikely to occur, and there is little energy loss, so resealability Tends to be good. On the other hand, when a filler that has not been surface-treated is added, the interfacial adhesion is poor and the composition is easily torn, so that the needle stick resistance tends to be reduced.
Among these, surface-treated talc, calcium carbonate, and clay are preferable, and talc and calcium carbonate are more preferable, from the viewpoint of the resealability and the like of the plug for a medical container containing the thermoplastic elastomer composition of the present embodiment. .

When the thermoplastic elastomer composition of the present embodiment is used as a material for a rubber stopper of a medical container, the rubber stopper is installed in a cap or a holder and steam sterilized at about 110 ° C. to 121 ° C. It is assumed that it will be. At this time, if the dimensions of the rubber stopper change due to heating, there is a possibility that a sufficient caulking effect cannot be obtained.
The present inventor uses surface-treated silica as the inorganic filler (e), so that when the thermoplastic elastomer composition is used as a rubber stopper for a medical container, steam sterilization treatment is performed. It has been found that it is possible to prevent deterioration of resealability afterwards.
By observing the surface state before and after the surface treatment by microscopic IR, it is possible to confirm whether the silica has been subjected to the “surface treatment”. In a state where the surface treatment is not performed, the surface of the silica is covered with a hydrophilic group, and the compatibility with the hydrocarbon resin and / or the hydrogenated block copolymer is not high. On the other hand, when the surface of silica is treated with a fatty acid or the like, the surface is modified with a hydrocarbon, so that the compatibility with the hydrocarbon resin and / or the hydrogenated block copolymer is improved. Along with this, the dispersion of silica in the hydrocarbon-based resin and / or the hydrogenated block copolymer also becomes good, and the adhesion at the interface is also improved.
The surface state of inorganic fillers other than silica can be observed by the same method as described above.

Examples of a method for obtaining the inorganic filler (e) include a method in which a surface treatment agent and / or a solution thereof is brought into contact with the surface of silica.
For example, when the surface treatment agent is a fatty acid, a resin acid, a fat, or a surfactant, as a dry treatment, a powdery surface treatment agent is mixed with silica, and a crusher such as a heated ball mill or roller mill is used. Alternatively, the surface treatment is performed by melting and chemically reacting while pulverizing with a mixer such as a ribbon blender or a Henschel mixer.
When using a water-insoluble material having a high melting point as a surface treatment agent, it is in an emulsion state or as a solution dissolved in alcohol, and is stirred and mixed with silica while being poured into a pulverizer or a mixer. The surface treatment is performed by drying.
As the wet treatment, a surface treatment agent is added to a slurry at the time of synthesis of silica, and the mixture is stirred with a mixer or the like while heating, whereby the silica is subjected to surface treatment. When a material having a high melting point is used as a surface treatment agent, it is used in an emulsion state, and is similarly added during the synthesis of silica and stirred to perform surface treatment.
When a coupling agent is used as a surface treatment agent, for a water-soluble one, the pH of a mixture of water and ethanol is usually adjusted, then the coupling agent is added to the solution, and a heated Henschel mixer containing silica is used. By spraying into a high-speed stirring mixer such as the above, a chemical reaction with the surface of silica is performed to perform a surface treatment. When a water-insoluble coupling agent is used as the surface treatment agent, the coupling agent is dissolved in acetone, alcohol, or the like, and sprayed into a heated high-speed stirring mixer containing silica in the same manner as described above. Thereby, the surface treatment of silica is performed.
It should be noted that surface treatment can be performed on materials other than silica by the same method.

  Typical surface treatment agents include fatty acids, resin acids, oils and fats, surfactants, silicone oils, and coupling agents (silane-based, titanium-based, phosphoric-acid-based, carboxylic acid-based, etc.), but silica, and The material is not limited to these as long as it can act on the surface of other inorganic fillers according to.

  Examples of the fatty acid include, but are not limited to, caproic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, saturated fatty acids such as behenic acid, and the like. Metal salts and modified products thereof; unsaturated fatty acids such as oleic acid, linoleic acid, erucic acid, eicosadienoic acid, docosadienoic acid, linolenic acid, eicosatetraenoic acid, tetracosapentaenoic acid, and docosahexaenoic acid; Metal salts and their modified products.

  Examples of the resin acid include, but are not limited to, abietic acid, neoabietic acid, parastolic acid, pimaric acid, isopimaric acid, rosin mainly containing dehydroabietic acid and the like, and derivatives thereof. Is mentioned.

  Examples of the fats and oils include, but are not limited to, soybean oil, linseed oil, coconut oil, and safflower oil.

  Examples of the surfactant include, but are not limited to, fatty acid type anionic surfactants such as sodium stearate and potassium stearate; and polyoxyethylene alkyl ether sulfates and long-chain alcohol sulfates. , Their sodium salts, potassium salts and other sulfate ester-type anionic surfactants; alkylbenzenesulfonic acid, alkylnaphthalenesulfonic acid, paraffinsulfonic acid, α-olefinsulfonic acid, alkylsulfosuccinic acid, etc .; Sulfonic acid type anionic surfactants such as salts; and nonionic surfactants such as polyethylene glycol, polyvinyl alcohol and derivatives thereof.

  Examples of the silicone oil include, but are not limited to, dimethyl silicone oil, methylphenyl silicone oil, methyl hydrogen silicone oil, amino-modified silicone oil, epoxy-modified silicone oil, carboxy-modified silicone oil, and rubinol-modified Examples include silicone oil, polyether-modified silicone oil, alkyl-modified silicone oil, and fluorine-modified silicone oil.

  The silane coupling agent is not limited to the following, but includes, for example, dimethyldichlorosilane, trimethylchlorosilane, dimethyldimethoxysilane, trimethylmethoxysilane, dimethyldiethoxysilane, n-propyltrimethoxysilane, n-propyl Alkyl group-containing silane coupling agents such as triethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, and polydimethylsiloxane; phenyl group-containing silane coupling agents such as phenyltrichlorosilane, phenyltrimethoxysilane, and phenyltriethoxysilane; Vinyl group-containing silane coupling agents such as vinyltrimethoxysilane and vinyltriethoxysilane; styryl group-containing silane coupling agents such as p-styryltrimethoxysilane; Epoxy group-containing silane coupling agent such as doxypropylmethyldimethoxysilane; methacryl group-containing silane coupling agent such as 3-methacryloxypropylmethyldimethoxysilane; acrylic group-containing silane coupling agent such as 3-acryloxypropylmethyldimethoxysilane Agents; silane coupling agents containing an amino group such as hexamethyldisilazane and N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane; and the like.

  Examples of the titanium-based coupling agent include, but are not limited to, titanium isostearate, tetrastearyl titanate, tetraisopropyl titanate, isopropyl triisostearoyl titanate, titanium octylene glycolate compound, titanium diethanol aminate, Titanium aminoethylaminoethanolate, bis (dioctylpyrophosphate) oxyacetate titanate, tris (dioctylpyrophosphate) ethylene titanate, isopropyldioctylpyrophosphate titanate, isopropyltris (dioctylpyrophosphate) titanate, isopropyltris (dodecylbenzenesulfonyl) titanate, Titanium tetranormal butoxide, titanium tetra-2-ethylhexoxy , Tetraoctylbis (ditridecylphosphite) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetra (2,2-diallyl-1-butyl) bis (ditridecyl) phosphite titanate, and the like.

  Examples of the phosphate coupling agent include, but are not limited to, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, and triunyl phosphate. Decyl phosphate, tridodecyl phosphate, tritridecyl phosphate, tritetradecyl phosphate, tripentadecyl phosphate, trihexadecyl phosphate, triheptadecyl phosphate, trioctadecyl phosphate, trioleyl phosphate, triphenyl phosphate, tricresyl phosphate, tricixile Phosphoric acid triacetate such as nyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate Ter: monobutyl acid phosphate, monopentyl acid phosphate, monohexyl acid phosphate, monoheptyl acid phosphate, monooctyl acid phosphate, monononyl acid phosphate, monodecyl acid phosphate, monoundecyl acid phosphate, monododecyl acid triphosphate, monododecyl acid monophosphate Decyl acid phosphate, monotetradecyl acid phosphate, monopentadecyl acid phosphate, monohexadecyl acid phosphate, monoheptadecyl acid phosphate, monooctadecyl acid phosphate, monooleyl acid phosphate, dibutyl acid phosphate, dipentyl acid phosphate, dihexyl acid The Butyl acid phosphate, dioctyl acid phosphate, dinonyl acid phosphate, didecyl acid phosphate, diundecyl acid phosphate, didodecyl acid phosphate, ditridecyl acid phosphate, ditetradecyl acid phosphate, dipentadecyl acid phosphate, dihexadecyl Acid phosphates such as diheptadecyl acid phosphate, dioctadecyl acid phosphate, and dioleyl acid phosphate; tributyl phosphorothioate, tripentyl phosphorothionate, trihexyl phosphorothionate, triheptyl phosphorothionate, Trioctyl phosphorothionate, trinonyl phosphorothionate, tridecylpho Sporothionate, triundecylphosphorothionate, tridodecylphosphorothionate, tritridecylphosphorothionate, tritetradecylphosphorothionate, tripentadecylphosphorothionate, trihexadecylphosphorothionate , Triheptadecyl phosphorothionate, trioctadecyl phosphorothionate, trioleyl phosphorothionate, triphenyl phosphorothionate, tricresyl phosphorothionate, trixylenyl phosphorothionate, cresyl diphenyl phosphate Thiophosphoric acid esters such as forotionate and xylenyldiphenylphosphorothionate; tris-dichloropropyl phosphate, tris-chloroethyl phosphate, tris-chlorophenyl phosphate, Chlorinated phosphates such as loxyalkylene-bis [di (chloroalkyl)] phosphate; dibutyl phosphite, dipentyl phosphite, dihexyl phosphite, diheptyl phosphite, dioctyl phosphite, dinonyl phosphite, didecyl phosphite Phyte, diundecyl phosphite, didodecyl phosphite, dioleyl phosphite, diphenyl phosphite, dicresyl phosphite, tributyl phosphite, tripentyl phosphite, trihexyl phosphite, triheptyl phosphite, trioctyl phosphite, Trinonyl phosphite, tridecyl phosphite, triundecyl phosphite, tridodecyl phosphite, trioleyl phosphite, triphenyl phosphite, tricresyl Phosphites such as Sufaito, and the like.

  Examples of the carboxylic acid-based coupling agent include, but are not limited to, carboxylated polybutadiene and its hydrogenated product, carboxylated polyisoprene and its hydrogenated product, carboxylated polyolefin, carboxylated polystyrene, and carboxylated polybutadiene. Styrene-butadiene copolymer and its hydrogenated product, carboxylated nitrile rubber, and the like.

Among these, when the thermoplastic elastomer composition of the present embodiment is used as a plug, particularly when used as a material for a plug of a medical container, from the viewpoint of resealability after steam sterilization, as a surface treatment agent, A silane coupling agent is preferable, and a trimethylsilyl silane coupling agent and a dimethylsilyl silane coupling agent are more preferable.
As described above, the surface treatment tends to improve the interfacial adhesion between silica and the hydrogenated block copolymer (a) or the polypropylene-based resin (b). In particular, trimethylsilyl-based silane is used as a silica surface treatment agent. By using a coupling agent and a dimethylsilyl-based silane coupling agent, interfacial peeling is more unlikely to occur. This is considered to be due to a chemical bond between the trimethylsilyl-based silane coupling agent and the dimethylsilyl-based silane coupling agent and silica.

  In the thermoplastic elastomer of the present embodiment, other inorganic fillers to be combined with the surface-treated silica include calcium carbonate surface-treated with a fatty acid and a modified product thereof from the viewpoint of resealability after steam sterilization. Is preferred.

In the thermoplastic elastomer composition of the present embodiment, the content of the surface-treated silica as the inorganic filler (e) is 1 to 150 parts by mass with respect to 100 parts by mass of the hydrogenated block copolymer (a). Yes, preferably 3 to 130 parts by mass, more preferably 5 to 110 parts by mass, still more preferably 10 to 100 parts by mass, and still more preferably 15 to 90 parts by mass.
If the content of the surface-treated silica as the inorganic filler (e) is within the above range, the plug containing the thermoplastic elastomer composition of the present embodiment, particularly the plug used for a medical container, is excellent. Needle retention tends to be obtained.

The average primary particle diameter of silica as the inorganic filler (e) is preferably 0.001 μm to 2 μm.
A more preferred upper limit of the average primary particle size is 1 μm, and further preferably 0.05 μm. A more preferred lower limit of the average primary particle size is 0.01 μm, and still more preferably 0.015 μm.
When the average primary particle size of the silica as the inorganic filler (e) is 0.001 μm or more, the effect of improving the flexibility of the thermoplastic elastomer composition is obtained, and when the average primary particle size is 2 μm or less, the thermoplastic elastomer composition The effect of improving the uniform dispersibility in the product can be obtained.
In addition, in the thermoplastic elastomer composition of this embodiment, as described above, in addition to the surface-treated silica, an inorganic filler that has not been surface-treated may be used in combination as another inorganic filler.
The effect of reducing the needle stick resistance can be expected by adding a non-surface-treated inorganic filler to lower the interfacial adhesion. From the viewpoint of maintaining good resealability, it is preferable that the upper limit of the amount of the inorganic filler that has not been surface-treated be about half of the total amount of the added inorganic filler.

(Inorganic porous adsorbent (f))
The thermoplastic elastomer composition of the present embodiment may further contain an inorganic porous adsorbent (f) from the viewpoint of improving odor.

As the inorganic porous adsorbent (f), a powdery porous inorganic compound having a specific surface area of 50 m ² / g or more by a BET method is preferable, and is not limited to the following. For example, zeolite, The component consists of SiO ₂ and Al ₂ O ₃ , and not only a mixture of these components but also a compound having a three-dimensional crystal structure as one compound. Aluminosilicate having a composite skeleton represented by II); a composite of SiO ₂ and Al ₂ O ₃ with another metal oxide or metal salt (not a simple mixture but having a three-dimensional crystal structure as one compound) Porous silica such as silica gel and mesoporous silica; and porous ceramics such as activated carbon, γ-alumina, θ-alumina, and nano-sized titanium oxide.
These inorganic compounds may be used alone or in combination of two or more.
Among them, in the case of use as a plug for a medical container, zeolite; a composite of SiO ₂ and Al ₂ O ₃ with another metal oxide or metal salt is preferable from the viewpoint of improving odor.

_{^{(M I, M II 1/2)}} m (Al m Si n O 2 (m + n)) · xH 2 O ··· (II)
(Wherein, M ^I is Li ^+, Na ^+, 1 valent metal cation K ⁺ and the like, M ^II is Ca ^2+, Mg ^2+, a divalent metal cation of Ba ^2+, etc., there are a plurality In this case, they may be the same or different, and n and m are each an integer of 2 or more, and n ≧ m.)

The specific surface area of the inorganic porous adsorbent (f) measured by the BET method is preferably 50 m ² / g or more, more preferably 100 m ² / g or more, and further preferably 200 m ² / g or more.
In the thermoplastic elastomer composition of the present embodiment, surface-treated silica is used as the inorganic filler (e), and the silica has a specific surface area on the order of the numerical value, so that the inorganic porous adsorbent (f) Can be functioned as an adsorbent without separately adding silica.
When higher adsorption performance is required, it is preferable to further add an adsorbent having a higher specific surface area, such as porous silica, as the inorganic porous adsorbent (f). The specific surface area of the porous silica as the inorganic porous adsorbent (f) is preferably 400 m ² / g or more, more preferably 600 m ² / g or more, and further preferably 800 m ² / g or more.

In the thermoplastic elastomer composition of the present embodiment, the content of the inorganic porous adsorbent (f) is preferably from 1 to 30 parts by mass, more preferably from 100 parts by mass of the hydrogenated block copolymer (a). The amount is 3 to 30 parts by mass, further preferably 4 to 25 parts by mass, and still more preferably 5 to 20 parts by mass.
When the amount of the inorganic porous adsorbent (f) is within the above range, a thermoplastic elastomer composition more excellent in improving the odor of the plug of the present embodiment tends to be obtained.

(Organic peroxide (g))
The thermoplastic elastomer composition of the present embodiment may be partially crosslinked in the presence of an organic peroxide (g) from the viewpoint of recoverability.
Examples of the organic peroxide (g) include, but are not limited to, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide, and 2,5-dimethyl. -2,5-di (benzoylperoxy) hexane, t-butylperoxybenzoate, t-butylcumyl peroxide, diisopropylbenzene hydroxyperoxide, 1,3-bis (t-butylperoxyisopropyl) benzene, benzoyl peroxide, 1,1 -Di (t-butylperoxy) -3,3,5-trimethylcyclohexane, t-butyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, di-t-butyl peroxide, 1 , 1-Di-t-butylperoxy-cyclohexane 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, n-butyl-4,4-bis (t-butylperoxy) valerate, t-butylperoxyisobutyrate, t-butylperoxy -2-ethylhexanoate, t-butylperoxyisopropyl carbonate and the like.
These may be used alone or in combination of two or more organic peroxides.
The amount of the organic peroxide (g) used is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 4 parts by mass, and still more preferably 100 parts by mass of the hydrogenated block copolymer (a). Is 0.3 to 3 parts by mass.
When the amount of the organic peroxide (g) is within the above range, a thermoplastic elastomer composition having excellent recoverability tends to be obtained without lowering processability.

(Crosslinking aid (h))
When the thermoplastic elastomer composition of the present embodiment is partially crosslinked, a crosslinking aid can be used as needed to adjust the degree of crosslinking.
Examples of the crosslinking assistant (h) include, but are not limited to, trimethylolpropane triacrylate, triallyl isocyanurate, triallyl cyanurate, triallyl formal, triallyl trimellitate, N, N '-M-phenylene bismaleimide, dipropargyl terephthalate, diallyl phthalate, tetraallyl terephthalamide, triallyl phosphate, divinylbenzene, ethylene dimethacrylate, diallyl phthalate, quinone dioxime, ethylene glycol dimethacrylate, polyfunctional methacrylate monomer, Examples include polyhydric alcohol methacrylates and acrylates, unsaturated silane compounds (for example, vinyltrimethoxysilane, vinyltriethoxysilane, and the like).
One of these may be used alone, or two or more of them may be used in combination as needed.
The amount of the crosslinking aid (h) to be used is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 8 parts by mass, and still more preferably 100 parts by mass of the hydrogenated block copolymer (a). It is 0.5 to 7 parts by mass.

(Other components)
The thermoplastic elastomer composition of the present embodiment may further contain other additives in addition to the components (a) to (h) described above, as long as the object of the present embodiment is not impaired.
Other additives include heat stabilizers, antioxidants, ultraviolet absorbers, antioxidants, plasticizers, light stabilizers, crystal nucleating agents, impact modifiers, pigments, lubricants, antistatic agents, flame retardants, and flame retardants. Examples include a combustion aid, a compatibilizer, and a tackifier.
In particular, when silicone oil is added as a lubricant, slidability is improved, which is effective in reducing needle stick resistance and improving coring.
Examples of the type of silicone oil include general dimethylpolysiloxane and phenyl-methylpolysiloxane, and dimethylpolysiloxane is particularly preferred.
The amount of silicone oil added is preferably 0.5 to 10 parts by mass, more preferably 0.7 to 7 parts by mass, and still more preferably 1.0 to 100 parts by mass of the hydrogenated block copolymer (a). To 5 parts by mass. There is no particular restriction on the kinematic viscosity of silicone oil is preferably 10~10000mm ² / sec, more preferably 50~7000mm ² / sec, more preferably 100~5000mm ² / sec.
One of these additives may be used alone, or two or more thereof may be used in combination.

(Characteristics of thermoplastic elastomer composition)
The thermoplastic elastomer composition of the present embodiment has a Shore A hardness of 55 or less and a needle stick resistance of 4.0 Kgf or less from the viewpoints of flexibility, strain recovery, needle penetration, and liquid leakage resistance. More preferably, the Shore A hardness is 55 or less, the tear strength measured according to JIS K6252 is 45 N or less, and the needle stick resistance is 4.0 Kgf or less.
The needle puncture resistance was measured by using a tensile tester TG-5kN (manufactured by Minebea Co., Ltd.) and fixing the plug made of the thermoplastic elastomer of the present embodiment upward to a PET bottle, and measuring the diameter (root) from above. A resin needle (plastic bottle needle) having a maximum diameter of 5 mm is passed through the center of the plug 1 at a speed of 200 mm / min, and the maximum load at this time is measured.
If the Shore A hardness is 55 or less, the tear strength is 45 N or less, and the needle puncture resistance is 4.0 Kgf or less, sufficient flexibility and needle pierceability tend to be obtained more surely. It also tends to be excellent.
From the same viewpoint, more preferably, Shore A hardness is 53 or less, tear strength is 42 N or less, needle stick resistance is 3.7 Kgf or less, still more preferably Shore A hardness is 50 or less, and tear strength is 38 N or less. And needle stick resistance is 3.5 kgf or less.
Although there is no particular lower limit, the Shore A hardness is preferably 20 or more, the tear strength is 20 N or more, and the needle stick resistance is preferably 1.0 Kgf or more.
The Shore A hardness, tear strength, and needle stick resistance can be measured by the methods described in Examples described later.
In the thermoplastic elastomer of the present embodiment, the contents of the hydrogenated block copolymer (a), the polypropylene resin (b), and the non-aromatic softener (d) are adjusted or the hydrogenated block copolymer is used. In (a), the structure such as the content and molecular weight of the vinyl aromatic hydrocarbon compound monomer unit is adjusted, and in the components (b) to (c), the molecular weight, MFR, viscosity and the like are adjusted. Thereby, Shore A hardness, tear strength, and needle stick resistance can be controlled within the above numerical ranges.

In addition, the thermoplastic elastomer composition of the present embodiment has a “six-step odor intensity indication method” used in the Offensive Odor Prevention Law from the viewpoint of low odor and low elution properties (Odor Control Guide issued in April 2002). Book In the Ministry of the Environment, Environmental Management Bureau, Atmosphere and Living Environment Room), the odor intensity is preferably 3 or less, and more preferably 2.5 or less.
The odor intensity can be measured by the method described in Examples described later.

(Method for producing thermoplastic elastomer composition)
The method for producing the thermoplastic elastomer composition of the present embodiment is not particularly limited, and a conventionally known method can be applied.
For example, melting using a general kneader such as a pressure kneader, a Banbury mixer, an internal mixer, a lab plast mill, a mix lab, a single screw extruder, a twin screw extruder, a co-kneader, and a multi-screw extruder. A kneading method, a method of dissolving or dispersing and mixing each component and then removing the solvent by heating, and the like can be given.

When the thermoplastic elastomer composition of the present embodiment is partially crosslinked with the above-described organic peroxide (g), the components (a) to (f) are complexed and the organic peroxide (g) ( And partial crosslinking with a crosslinking assistant (h)) added if necessary, or after compounding components (a) to (f), an organic peroxide (g) and optionally If necessary, a crosslinking assistant (h) may be added for partial crosslinking.
Further, a part of the components (a) to (f) may be mixed with the organic peroxide (g) and, if necessary, the crosslinking aid (h), and after crosslinking, the remaining components may be mixed. .
The partial crosslinking can be performed at a temperature at which decomposition of the organic peroxide (g) to be used occurs, generally at a temperature of 150 to 250 ° C.
It is used when the compounding of a part or all of the components (a) to (f) and the crosslinking by the organic peroxide (g) (and the crosslinking assistant (h) added as necessary) are performed simultaneously. At a temperature at which the decomposition of the organic peroxide (g) occurs, the composition can be compounded by using the above-mentioned melt kneader or the like.

(Plug and container)
The plug of the present embodiment includes the thermoplastic elastomer composition of the present embodiment, and the container of the present embodiment includes the plug of the present embodiment.

(Application)
The stopper of the present embodiment is preferably used for a hermetic container or a hermetically sealed container for medical use, and in the case of puncturing an injection needle, a roughly cylindrical lid or a cylindrical jig in a predetermined jig. In a typical mode, a stopper is fitted and used integrally with a lid or a jig.
Examples of the jig include, but are not limited to, a predetermined framework, a cap, a housing, a sealing material, and the like. Specifically, the form used as a cap of an infusion bag is mentioned.
On the other hand, in some cases, the cylindrical stopper is used alone, and is fitted into the mouth of the glass bottle to function as a hermetic stopper.
In the case of an application that does not pierce the injection needle, a disc-shaped plug is fitted into the inner surface of the lid of the container that can be hermetically sealed with a screw or the like, thereby contributing to an improvement in hermeticity.
The container of the present embodiment includes the plug of the present embodiment.
The medical container is preferably an airtight container or an airtight container, and is not limited to the following, but examples include an infusion bag, a peritoneal dialysis bag, an infusion bottle, an infusion soft bottle, a glass vial, and a plastic vial.

  The shape of the plug according to the present embodiment is not particularly limited, and includes, for example, a truncated cone, a column, and a disk, and the diameter is usually about 5 to 25 mm. In the thickness of the plug of the present embodiment, that is, in the use of piercing a syringe needle, the thickness in the direction of piercing the syringe needle is not particularly limited, but is usually about 2 to 10 mm.

(Method of manufacturing the plug)
The plug is not particularly limited, but can be manufactured by, for example, injection molding, compression molding, or punching from extrusion molding.
From the viewpoint of dimensional accuracy and reproducibility of surface roughness, it is preferable to manufacture by injection molding.

Hereinafter, the present embodiment will be described in detail with reference to specific examples and comparative examples, but the present embodiment is not limited to the following examples.
First, evaluation methods and physical property measurement methods applied to Examples and Comparative Examples are described below.

[Evaluation method of hydrogenated block copolymer (a)]
((1) Weight average molecular weight, number average molecular weight, molecular weight distribution)
The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of the hydrogenated block copolymer (a) were obtained from a calibration curve (peak molecular weight of standard polystyrene) obtained from measurement of commercially available standard polystyrene. Was determined based on the molecular weight of the peak in the chromatogram.
HLC-8320ECOSEC collection was used as measurement software, and HLC-8320ECOSEC analysis was used as analysis software.
(Measurement condition)
GPC; HLC-8320GPC (Tosoh Corporation)
Detector; RI
Detection sensitivity: 3MV / min Sampling pitch: 600MSEC
Column: 4 TSKGEL SUPERHZM-N (6MMI.D × 15CM) (manufactured by Tosoh Corporation)
Solvent; THF
Flow rate: 0.6 ML / min Concentration: 0.5 MG / ML
Column temperature; 40 ° C
Injection volume: 20 ML

((2) Number average molecular weight of polymer block A1 in hydrogenated block copolymer (a-1) and polymer block A2 in hydrogenated block copolymer (a-2))
The number average molecular weight Mn of the polymer block A1 in the hydrogenated block copolymer (a-1) and the polymer block A2 in the hydrogenated block copolymer (a-2), that is, the polystyrene block, are as follows: M. KOLTHOFF, et al. , J. et al. Polym. Soi. 1,429 (1946), <hydrogenated block copolymers (1) to (8), (12)> and <hydrogenated block copolymers (9) to (11) described below. ), (13)> is oxidatively decomposed with t-butyl hydroperoxide using osmium tetroxide as a catalyst, and the same as the method described in ((1) weight average molecular weight, number average molecular weight, molecular weight distribution), The number average molecular weight in terms of polystyrene was measured by using GPC.

((3) Content of polystyrene block in hydrogenated block copolymers (a-1) and (a-2))
The content of the polystyrene block is as follows: <hydrogenated block copolymers (1) to (8), (12)> and <hydrogenated block copolymers (9) to (11), (13)> Using osmium as a catalyst, it is oxidatively decomposed with t-butyl hydroperoxide, then precipitated with methanol, separated into solid and liquid, and the precipitate was measured using an ultraviolet spectrophotometer (manufactured by Shimadzu Corporation, UV-2450). It was determined by calculating the polystyrene block content from the peak intensity of the absorption wavelength (262 nm) attributed to the vinyl aromatic compound component (styrene) using a calibration curve.

((4) Content of all vinyl aromatic hydrocarbon compound monomer units (total styrene content))
A fixed amount of the hydrogenated block copolymer is dissolved in chloroform and measured with an ultraviolet spectrophotometer (manufactured by Shimadzu Corporation, UV-2450). The content of the vinyl aromatic hydrocarbon monomer unit (styrene) was calculated from the peak intensity in (2) using a calibration curve.

((5) Vinyl bond amount)
The vinyl bond amount of the conjugated diene monomer unit in the block copolymer was measured using a nuclear magnetic resonance apparatus (NMR) under the following conditions.
A large amount of methanol was added to the reaction solution after the completion of all the reactions (for the hydrogenated block copolymer, after the hydrogenation reaction) to precipitate and recover the block copolymer. Next, the block copolymer was extracted with acetone, and the extract was dried under vacuum and used as a sample for ¹ H-NMR measurement.
The conditions of ¹ H-NMR measurement are described below.
(Measurement condition)
Measuring equipment: JNM-LA400 (manufactured by JEOL)
Solvent: deuterated chloroform Sample concentration: 50 MG / ML
Observation frequency: 400MHZ
Chemical shift standard: TMS (tetramethylsilane)
Pulse delay: 2.904 seconds Number of scans: 64 Pulse width: 45 °
Measurement temperature: 26 ° C
The amount of vinyl bond was determined based on the total area of all peaks (1,2-bond, 3,4-bond, 1,4-bond) related to the conjugated diene monomer unit in the obtained peak, 1,2-bond and It was determined from the ratio of the total area of the peaks of the 3,4-bond.

((6) Hydrogenation rate (hydrogenation rate))
The hydrogenation rate of the double bond of the conjugated diene monomer unit in the block copolymer was measured using a nuclear magnetic resonance apparatus (NMR) under the same conditions as in ((5) Vinyl bond amount).
The hydrogenation rate was determined by the ratio of water to the total area of all peaks (1,2-bond, 3,4-bond, 1,4-bond) related to the double bond in the conjugated diene monomer unit in the obtained peak. It was determined by calculating the ratio of the peak total area of the added 1,2-bond, the hydrogenated 3,4-bond, and the hydrogenated 1,4-bond.

[Evaluation method of polyphenylene ether resin (c)]
((7) Reduced viscosity of polyphenylene ether resin (c))
A 0.5 g / dL chloroform solution of the polyphenylene ether resin (c) was prepared, and the reduced viscosity (ηsp / c) [dL / g] at 30 ° C. was determined using an Ubbelohde viscosity tube.

((8) Number average molecular weight of polyphenylene ether resin (c))
It measured using GPC and HLC-8320GPC (made by Tosoh Corporation) under the same conditions as the above (1).

((9) Average particle size of polyphenylene ether resin (c))
The average particle size of the polyphenylene ether resin (c) was measured three or more times by dispersing in a 1-butanol solvent using a laser diffraction type particle size distribution analyzer (manufactured by Coulter, product name: LS-230) and measuring each volume. The arithmetic mean value of the average median diameter was defined as the average particle diameter.

(Production of thermoplastic elastomer composition)
(Examples 1 to 59, Comparative Examples 1 to 23)
Based on the blending ratio (parts by mass) shown in Tables 3 to 11, the melt-kneaded mixture is set at a set temperature of 230 ° C. by a twin-screw extruder (“TEX-30αII” manufactured by Nippon Steel Works, cylinder diameter: 30 mm) to obtain a thermoplastic elastomer. A pellet of the composition was obtained.

(Evaluation method of thermoplastic elastomer composition)
((10) Melt flow rate (MFR))
The melt flow rate (MFR) of the pellets of the thermoplastic elastomer composition obtained as described above was measured under the conditions of a temperature of 230 ° C. and a load of 2.16 kg in accordance with ASTM D1238.

[Preparation of press sheet]
The pellets of the thermoplastic elastomer composition obtained as described above were used at 50 ° C. by a Toho Press Seisakusho using a mold (size: 110 mm × 220 mm × 2 mm thick) at 200 ° C. Pressing was performed for 5 minutes at 200 ° C. and 100 kgf / cm ² under a pressurization condition of 5 kgf / cm ² for 2 minutes to produce a 2 mm-thick press sheet.
Using the obtained press sheet, physical properties were measured according to the following measurement methods.

[Press sheet evaluation method]
((11) hardness)
It was measured using a type A durometer according to JIS K6253.
When the Shore A hardness was 55 or less, it was determined that the resin had sufficient flexibility.

((12) Tear strength)
In accordance with JIS K6252, the tear strength was measured at a test speed of 200 mm / min using an angle-shaped test piece having no cut.

(Manufacture of plugs)
Using the pellets of the thermoplastic elastomer composition obtained in the above [Production of thermoplastic elastomer], a cylindrical plug 1 having a diameter of 20 mm and a thickness of 4 mm was molded with an injection molding machine FE120S18A (manufactured by Nissei Plastics Industries, Ltd.). did.
1A shows a schematic top view of the plug 1, and FIG. 1B shows a schematic sectional view of the plug 1.
The injection molding conditions were as follows: resin temperature: 240 ° C., injection speed: 45 cm ³ / sec, injection time: 10 seconds, mold temperature: 40 ° C., cooling time: 40 seconds.

(Evaluation method of plug)
((13) Needle stick resistance)
The plug 1 shown in FIG. 1 was fitted into a predetermined jig as shown in FIG.
2A shows a schematic top view of the jig 2, and FIG. 2B shows a schematic cross-sectional view of the jig 2.
The jig 2 has a tubular holder 22 that can be attached to an object to be plugged via a screw pitch portion 21 at the mouth of a predetermined container.
The plug 1 was fitted into the opening end of the jig 2 and fixed with a retaining ring 23.
Next, a jig 2 in which the plug 1 was fitted was attached to and fixed to the plug portion of the plastic bottle filled with 500 mL of water.
The above-mentioned plastic bottle is fixed to a tensile tester TG-5kN (manufactured by Minebea Co., Ltd.) with the stopper 1 facing upward, and a resin needle (plastic bottle needle) having a diameter (root maximum diameter) of 5 mm is inserted from above. The plug 1 was penetrated into the center of the plug 1 at a speed of 200 mm / min. The maximum load at this time was measured.
The needle used was a Terfusion infusion set (TK-U200L) manufactured by Terumo Corporation.
It was determined that the smaller the maximum load, the lower the needle sticking resistance and the better.
The number of measurements was four, and the measured values were simply averaged.
In the judgment, ○: 4 kgf or less, x: exceeding 4 kgf, and ○ was evaluated as being practically good.

((14) Resealability after steam sterilization)
First, the plug 1 shown in FIG. 1 was fitted into a predetermined jig 2 as shown in FIG.
Next, the holding ring 23 is fixed with another jig so that the holding ring 23 is completely in contact with the holder 22 in which the plug 1 is fitted. And steam sterilization at a steam pressure of 0.104 MPa.
Thereafter, the mixture was cooled in the apparatus for 2 hours, taken out, and further cooled at room temperature of 23 ° C. for 2 hours. Then, similarly to ((13) Needle stick resistance), the plug 1 of FIG. The jig 2 was attached to the stopper of a plastic bottle filled with 500 mL of water and fixed.
The bottle was inverted and the stopper was on the bottom. At that time, the height from the inner surface of the stopper to the liquid surface was 18.5 cm.
A hole having a diameter of 3 mm was formed at the bottom (upper side) of the bottle, and a resin needle (plastic bottle needle) having a diameter (maximum root diameter) of 5 mm was pierced into the center of the plug 1 to the maximum diameter of the needle.
The needle was left as it was for 4 hours, the needle was pulled out, and the mass of water leaked from the needle stick mark was measured.
The smaller the amount of leakage, the better the resealability.
The number of measurements was 8, and a simple average was used as the measured value.
Judgment: ◎: Leakage of 0.5 g or less, ：: Leakage of more than 0.5 g and 1.0 g or less, ×: Leakage of more than 1.0 g, ◎ extremely excellent, ○ practically good Assessed that there is.

((15) Odor sensory test)
100 g of the thermoplastic elastomer composition pellets were put in a 500 mL pressure-resistant glass bottle, sealed, heated at 70 ° C. for 1 hour, and then left at room temperature for 48 hours.
Thereafter, ten test subjects confirmed odor from the mouth of the glass bottle and evaluated according to the following <odor intensity>.
The judgment was performed by calculating the average value of the following odor intensities and by the following criteria.
：: Odor intensity was less than 3, ×: Odor intensity was 3 or more, and ○ was evaluated as being practically good.
<Odor intensity>
0; no odor, 1; barely perceived odor, 2; weak odor to understand what odor, 2.5; intermediate between 2 and 3, 3; easily detectable odor, 3.5; intermediate between 3 and 4, 4; Strong smell, 5 strong smell

((16) Coring properties)
In the same manner as described above ((13) Needle stick resistance), the plug 1 of FIG. 1 was fitted into the jig 2 of FIG. 2, and attached and fixed to the plug of a plastic bottle filled with 500 mL of water.
After piercing five times a resin needle (plastic bottle needle) with a diameter (maximum root diameter) of 5 mm into the center of the plug 1 of the bottle 5 times, visually check whether there is any shavings of the plug in the water or on the surface of the needle. did.
Those having no shavings were judged to have good coring properties.
The number of measurements was 5, and the judgment was ○: no shavings on all, ×: even with one shaving, and ○ was evaluated as being practically good.

((17) Dissolution test method)
Using the press sheet obtained in the above [Preparation of press sheet], properties, pH, zinc, potassium permanganate-reducing The substances, evaporation residues and UV absorption spectra were measured.
The determination was based on the elution test for rubber stopper test for infusion of the 17th revised Japanese Pharmacopoeia and was as follows.
<Properties>
The prepared test solution was colorless and transparent, and the transmittances at wavelengths of 430 nm and 650 nm were measured using the blank test solution as a control, according to the 17th revision Japanese Pharmacopoeia Rubber Plug Test for Infusion Eluate test. Compliant with 9% or more.
<PH>
According to the 17th revision Japanese Pharmacopoeia, the pH of the prepared test solution and the blank test solution were measured according to the eluate test of the rubber stopper test method for infusion by the Japanese Pharmacopoeia, and the difference was evaluated as 1.0 or less, and the conformity was evaluated.
<Zinc>
The test was performed by the atomic absorption spectrophotometry method, and the absorbance of the prepared sample solution was evaluated to be conformable if the absorbance of the prepared sample solution was equal to or less than the absorbance of the standard solution in accordance with the elution test for rubber stopper test for infusion of the 17th revised edition of the Japanese Pharmacopoeia.
In Tables 10 and 11, the case of conformity is indicated by “〇”, and the case of non-conformity is indicated by “×”.
<Potassium permanganate reducing substance>
The prepared test solution and blank test solution were titrated with a 0.001 mol / L sodium thiosulfate solution according to the 17th revision of the Japanese Pharmacopoeia, rubber stopper test method for infusion, eluate test, to give a 0.002 mol / L excess solution. When the difference in consumption amount of the potassium manganate solution was 2.0 mL or less, it was evaluated as conformable.
<Evaporation residue>
The prepared test solution was evaporated to dryness, and the residue after drying was evaluated to be 2.0 mg or less according to the 17th revision Japanese Pharmacopoeia, Japanese Pharmacopoeia, Rubber Plug Test for Infusion Dissolution Test.
<UV absorption spectrum>
In accordance with the 17th Revised Japanese Pharmacopoeia, Rubber Plug Test Method for Infusion, Eluate test, the prepared test solution was tested by the UV-visible absorbance measurement method using the blank test solution as a control, and the absorbance at a wavelength of 220 to 350 nm. Was determined to be acceptable when the difference was 0.20 or less.

  Next, each component used will be described.

<Preparation of hydrogenation catalyst>
In Examples and Comparative Examples described later, a hydrogenation catalyst used for producing a hydrogenated block copolymer was prepared by the following method.
A reaction vessel equipped with a stirrer was purged with nitrogen, and 1 L of dried and purified cyclohexane was charged therein.
Next, 100 mmol of bis (η5-cyclopentadienyl) titanium dichloride was added.
While sufficiently stirring this, an n-hexane solution containing 200 mmol of trimethylaluminum was added and reacted at room temperature for about 3 days to obtain a hydrogenation catalyst.

<Hydrogenated block copolymer (1)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 5 parts by mass of a 1,3-butadiene monomer was charged, and then 0.080 parts by mass of n-butyllithium and 100 parts by mass of all monomers, and n-butyllithium (TMEDA) was added to n- 0.38 mol was added to 1 mol of butyllithium, and polymerization was carried out at 70 ° C. for 15 minutes.
Next, a cyclohexane solution containing 18 parts by mass of a styrene monomer was added, and polymerization was performed at 70 ° C. for 25 minutes. Further, a cyclohexane solution containing 60 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 70 ° C. for 40 minutes.
Finally, a cyclohexane solution containing 17 parts by mass of a styrene monomer was added, and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

Next, the hydrogenation catalyst was added to the obtained polymer in an amount of 100 ppm as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C.
After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate was added as a stabilizer to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (1) was obtained.

  The obtained hydrogenated block copolymer (1) had a total styrene content of 34.3% by mass, a polystyrene block content of 33.8% by mass, and a vinyl bond amount in the polybutadiene block before hydrogenation of 37.5 mol%. The weight average molecular weight of the whole polymer was 204,000, the number average molecular weight of the polystyrene block was 34,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.35. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.8%.

<Hydrogenated block copolymer (2)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, after adding a cyclohexane solution containing 16 parts by mass of a styrene monomer, 0.067 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.48 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Then, a cyclohexane solution containing 69 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (2) was obtained.

  The obtained hydrogenated block copolymer (2) had a total styrene content of 30.7% by mass, a polystyrene block content of 30.1% by mass, and a vinyl bond amount in the polybutadiene block before hydrogenation of 39.4 mol%. The weight average molecular weight of the entire polymer was 264,000, the number average molecular weight of the polystyrene block was 39,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.31. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

<Hydrogenated block copolymer (3)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 16 parts by mass of a styrene monomer was added, and then 0.067 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and 0.45 mol of TMEDA was added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Then, a cyclohexane solution containing 69 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 70 ppm of the above hydrogenation catalyst was added as titanium per 100 parts by mass of the polymer to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (3) was obtained.

  The obtained hydrogenated block copolymer (3) had a total styrene content of 31.3% by mass, a polystyrene block content of 31% by mass, a vinyl bond amount in the polybutadiene block before hydrogenation of 35.6 mol%, and a polymer The weight average molecular weight of the whole was 2670,000, the number average molecular weight of the polystyrene block was 40,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.28. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 76.3%.

<Hydrogenated block copolymer (4)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 16 parts by mass of a styrene monomer was charged, and then 0.044 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and 0.50 mol of TMEDA was added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Next, a cyclohexane solution containing 70 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 14 parts by mass of styrene monomer was added, and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (4) was obtained.

  The obtained hydrogenated block copolymer (4) had a total styrene content of 29.8 mass%, a polystyrene block content of 29.4 mass%, and a vinyl bond content of 34.7 mol% in the polybutadiene block before hydrogenation. The weight average molecular weight of the whole polymer was 423,000, the number average molecular weight of the polystyrene block was 61,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.34. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.1%.

<Hydrogenated block copolymer (5)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 17 parts by mass of a styrene monomer was charged, and then 0.115 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and 0.35 mol of TMEDA was added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Next, a cyclohexane solution containing 67 parts by mass of 1,3-butadiene monomer was added and polymerized at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 16 parts by mass of styrene monomer was added and polymerized at 70 ° C. for 25 minutes.
Next, 0.2 mol of silicon tetrachloride was added to 1 mol of n-butyllithium, and a coupling reaction was performed for 20 minutes. After the completion of the reaction, 0.15 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (5) was obtained.

  The obtained hydrogenated block copolymer (5) had a total styrene content of 33.1% by mass, a polystyrene block content of 32.9% by mass, and a vinyl bond amount before hydrogenation in the polybutadiene block of 37.3% by mol. The weight average molecular weight of the entire polymer was 413,000, the number average molecular weight of the polystyrene block was 34,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.35. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

<Hydrogenated block copolymer (6)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, after adding a cyclohexane solution containing 16 parts by mass of a styrene monomer, 0.142 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.24 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Next, a cyclohexane solution containing 70 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 14 parts by mass of styrene monomer was added, and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (6) was obtained.

  The obtained hydrogenated block copolymer (6) had a total styrene content of 30.2% by mass, a polystyrene block content of 29.7% by mass, and a vinyl bond amount in the polybutadiene block before hydrogenation of 33.3 mol%. The weight average molecular weight of the entire polymer was 88,000, the number average molecular weight of the polystyrene block was 22,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.27. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.7%.

<Hydrogenated block copolymer (7)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 28 parts by mass of a styrene monomer is added, and then 0.078 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.8 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 30 minutes.
Next, a cyclohexane solution containing 45 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 60 ° C. for 60 minutes. Finally, a cyclohexane solution containing 27 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 30 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (7) was obtained.

  The obtained hydrogenated block copolymer (7) had a total styrene content of 55.3% by mass, a polystyrene block content of 55.1% by mass, and a vinyl bond amount in the polybutadiene block of 66.8 mol% before hydrogenation. The weight average molecular weight of the entire polymer was 208,000, the number average molecular weight of the polystyrene block was 56,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.33. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.5%.

<Hydrogenated block copolymer (8)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 16 parts by mass of a styrene monomer was added, and then 0.066 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and 0.45 mol of TMEDA was added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Then, a cyclohexane solution containing 69 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 70 ° C. for 40 minutes. Finally, a cyclohexane solution containing 15 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 50 ppm of the above hydrogenation catalyst was added as titanium to 100 parts by mass of the polymer to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (8) was obtained.

  The obtained hydrogenated block copolymer (8) had a total styrene content of 30.8% by mass, a polystyrene block content of 30.1% by mass, and a vinyl bond amount in the polybutadiene block before hydrogenation of 36.4 mol%. The weight average molecular weight of the whole polymer was 283,000, the number average molecular weight of the polystyrene block was 42,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.26. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 56.1%.

<Hydrogenated block copolymer (9)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 5 parts by mass of a 1,3-butadiene monomer was charged, and then 0.085 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and TMEDA was added by 1 mol to 1 mol of n-butyllithium. 0.5 mol, and further 0.04 mol of sodium-t-pentoxide per mol of n-butyllithium were added, and polymerization was carried out at 60 ° C for 20 minutes.
Next, a cyclohexane solution containing 7 parts by mass of a styrene monomer was added, and polymerization was performed at 70 ° C. for 20 minutes. Further, a cyclohexane solution containing 82 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 60 ° C. for 1.5 hours.
Finally, a cyclohexane solution containing 6 parts by mass of a styrene monomer was added and polymerization was performed at 70 ° C. for 20 minutes. After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (9) was obtained.

  The obtained hydrogenated block copolymer (9) had a total styrene content of 13.4% by mass, a vinyl bond content of 76.4 mol% in the polybutadiene block before hydrogenation, and a weight average molecular weight of the whole polymer of 18.3. The molecular weight distribution was 1.35. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.6%.

<Hydrogenated block copolymer (10)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, after adding a cyclohexane solution containing 10 parts by mass of a styrene monomer, 0.140 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.50 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 25 minutes.
Next, a cyclohexane solution containing 81 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 70 ° C. for 50 minutes. Finally, a cyclohexane solution containing 9 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (10) was obtained.

  The obtained hydrogenated block copolymer (10) had a total styrene content of 18.6% by mass, a vinyl bond amount in the polybutadiene block before hydrogenation of 52.1 mol%, and a weight average molecular weight of the whole polymer of 9.3. The molecular weight distribution was 1.24. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.8%.

<Hydrogenated block copolymer (11)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, after charging a cyclohexane solution containing 13 parts by mass of a styrene monomer, 0.066 parts by mass of n-butyllithium was added to 100 parts by mass of all monomers, and 1.5 mol of TMEDA was added to 1 mol of n-butyllithium. Further, 0.04 mol of sodium-t-pentoxide was added to 1 mol of n-butyllithium, and polymerization was performed at 70 ° C. for 25 minutes.
Next, a cyclohexane solution containing 75 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 60 ° C. for 1.5 hours. Finally, a cyclohexane solution containing 12 parts by mass of a styrene monomer was added, and polymerization was performed at 70 ° C. for 25 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (11) was obtained.

  The obtained hydrogenated block copolymer (11) had a total styrene content of 25.4% by mass, a vinyl bond content in the polybutadiene block before hydrogenation of 76.2 mol%, and a weight average molecular weight of the whole polymer of 26.3. The molecular weight distribution was 1.38. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.4%.

<Hydrogenated block copolymer (12)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, after a cyclohexane solution containing 22 parts by mass of a styrene monomer is added, 0.115 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.55 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 30 minutes.
Next, a cyclohexane solution containing 58 parts by mass of 1,3-butadiene monomer was added and polymerization was performed at 65 ° C. for 60 minutes. Finally, a cyclohexane solution containing 20 parts by mass of styrene monomer was added and polymerization was performed at 70 ° C. for 30 minutes.
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (12) was obtained.

  The obtained hydrogenated block copolymer (12) had a total styrene content of 42.3% by mass, a polystyrene block content of 42.1% by mass, and a vinyl bond amount in the polybutadiene block before hydrogenation of 58.6 mol%. The weight average molecular weight of the whole polymer was 122,000, the number average molecular weight of the polystyrene block was 26,000, and the molecular weight distribution of the hydrogenated block copolymer was 1.26. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.3%.

<Hydrogenated block copolymer (13)>
The batch reactor was washed, dried, and purged with nitrogen in a stirrer and jacketed reactor having an internal volume of 10 L to perform batch polymerization.
First, a cyclohexane solution containing 5 parts by mass of a styrene monomer is added, and then 0.078 parts by mass of n-butyllithium is added to 100 parts by mass of all monomers, and 0.8 mol of TMEDA is added to 1 mol of n-butyllithium. And polymerized at 70 ° C. for 20 minutes.
Next, a cyclohexane solution containing 81 parts by mass of 1,3-butadiene monomer was added, and polymerization was performed at 60 ° C. for 1.5 hours. Finally, a cyclohexane solution containing 4 parts by mass of a styrene monomer was added, and polymerization was performed at 70 ° C. for 20 minutes. .
After the completion of the polymerization reaction, 0.95 mol of methanol was added to 1 mol of n-butyllithium to deactivate the reaction catalyst and obtain a polymer.

  Next, 100 ppm by mass of the hydrogenation catalyst was added to the obtained polymer as titanium per 100 parts by mass of the polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa and a temperature of 85 ° C. After completion of the hydrogenation reaction, 0.3 parts by mass of octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer, and hydrogenated block was added. A copolymer (13) was obtained.

  The obtained hydrogenated block copolymer (13) had a total styrene content of 8.8% by mass, a vinyl bond amount in the polybutadiene block before hydrogenation of 65.1 mol%, and a weight average molecular weight of the whole polymer of 20.3%. The molecular weight distribution was 1.28. The hydrogenation rate of the aliphatic double bond derived from 1,3-butadiene was 99.8%.

<Polypropylene resin (b)>
The following commercially available products were used as the polypropylene resin (b).
Polypropylene resin (b): Sun Allomer Co., Ltd. PM801A, propylene homo 9 polymer, MFR (230 ° C., 2.16 kg) 13 g / 10 min

<Polyphenylene ether resin (c)>
The polyphenylene ether resin (c) was produced according to the following method.
Based on a known method, polyphenylene ether was polymerized by oxidative coupling polymerization of 2,6-dimethylphenol, and purified to obtain a polyphenylene ether resin (c).
The reduced viscosity (ηsp / c) (0.5 g / dL chloroform solution, measured at 30 ° C.), number average molecular weight, and average particle size of the obtained polyphenylene ether resin (c) are shown below.
(C-1): reduced viscosity = 0.45 dL / g, number average molecular weight = 1.740,000, average particle diameter = 290 μm

<Non-aromatic softener (d)>
The following commercially available products were used as the non-aromatic softener (d).
Non-aromatic softener (d-1): Diana Process Oil PW380 manufactured by Idemitsu Kosan Co., Ltd., paraffin-based oil, weight average molecular weight 750, kinematic viscosity (40 ° C.) = 380 mm ² / sec Non-aromatic softener (d- 2): Idemitsu Kosan Diana Process Oil PW90, paraffin oil, weight average molecular weight 530, kinematic viscosity (40 ° C.) = 90.5 mm ² / sec.

<Inorganic filler (e)>
The following commercially available products were used as the inorganic filler (e).
Inorganic filler (e-1): Whiten SB Red, manufactured by Shiraishi Calcium Co., Ltd., average particle size 1.8 μm, BET method / specific surface area 1.2 m ² / g, calcium carbonate Inorganic filler (e-2): Shiraishi Ryton A manufactured by Calcium Co., Ltd., average primary particle diameter 1.8 μm, BET method, specific surface area 3 m ² / g, modified fatty acid surface-treated calcium carbonate inorganic filler (e-3): Aerosil OX50 manufactured by Japan Aerosil Co., Ltd., average primary Particle diameter 40 nm, BET method / specific surface area 50 m ² / g, silica Inorganic filler (e-4): Aerosil R972V manufactured by Japan Aerosil Co., Ltd., average primary particle diameter 16 nm, BET method / specific surface area 110 m ² / g, dimethylsilyl Surface treated silica Inorganic filler (e-5): Aerosil R976S manufactured by Japan Aerosil Co., Ltd., average primary particle diameter 7 nm, BET method / ratio Area 240 m ² / g, dimethylsilyl surface treated silica inorganic filler (e-6): Nippon Aerosil Co., Ltd. Aerosil RX50, average primary particle diameter 40 nm, BET method, specific surface area 35m ² / g, trimethylsilyl surface treated silica inorganic filler Agent (e-7): Aerosil RY50 manufactured by Japan Aerosil Co., Ltd., average primary particle diameter 40 nm, BET method, specific surface area 30 m ² / g, dimethyl silicone oil surface-treated silica Inorganic filler (e-8): Japan Aerosil Co., Ltd. Aerosil R104, average primary particle diameter 12 nm, BET method / specific surface area 150 m ² / g, octamethylcyclotetrasiloxane surface-treated silica Inorganic filler (e-9): Aerosil RA200HS manufactured by Japan Aerosil Co., Ltd., average primary particle diameter 12 nm , BET method, specific surface area of 140m ² / g, f Sa hexamethyldisilazane and aminosilane surface treated silica inorganic filler (e-10): Nippon Aerosil Co., Ltd. Aerosil R805, average primary particle diameter 12 nm, BET method, specific surface area of 150m ² / g, octyl silane surface treated silica inorganic filler (E-11): Aerosil R711 manufactured by Japan Aerosil Co., Ltd., average primary particle diameter 12 nm, BET method / specific surface area 150 m ² / g, methacryloxysilane surface-treated silica inorganic filler (e-12): Kyowa Chemical Industry Co., Ltd. Kisuma 5B, average primary particle diameter 0.92 μm, BET method / specific surface area 4.3 m ² / g, higher fatty acid surface-treated magnesium hydroxide inorganic filler (e-13): Pyro Kisuma 5301K, manufactured by Kyowa Chemical Industry Co., Ltd., average The primary particle diameter of 2 [mu] m, BET method-specific surface area 1.4 m ² / g, table silane coupling agent Processing of magnesium oxide

<Inorganic porous adsorbent (f)>
The following commercially available product was used as the inorganic porous adsorbent (f).
Inorganic porous adsorbent (f-1): Molecular sieve USYZ2000 manufactured by Union Showa Co., Ltd., average particle diameter 3 to 5 μm, BET method, specific surface area 500 m ² / g, synthetic zeolite (sodium aluminosilicate)
Inorganic porous adsorbent (f-2): Seventol OM-1, manufactured by Osaka Gas Chemical Co., Ltd., average particle diameter 2 to 2.5 μm, BET method, specific surface area ≧ 200 m ² / g, synthetic zeolite (sodium aluminosilicate)

<Silicone oil>
The following commercially available silicone oil was used.
Silicone oil: SH200 • 100Cs manufactured by Dow Corning Toray Co., Ltd., dimethylpolysiloxane, kinematic viscosity 100 mm ² / sec

The types and physical properties of the hydrogenated block copolymers (a-1) and (a-2) contained in the hydrogenated block copolymer (a) are shown in Tables 1 and 2 below.
The type of the block copolymer is represented by A for the styrene block and B for the butadiene block in both the hydrogenated block copolymers (a-1) and (a-2).
Tables 3 to 11 show the composition and properties of the thermoplastic elastomer composition.

  The thermoplastic elastomer composition of the present invention and the plug of a medical container using the same have an excellent balance of needle stick resistance, resealability, coring resistance, and the like. Further, since it is excellent in processability, moldability and hygiene as compared with vulcanized rubber, it has industrial applicability as a plug for various medical containers such as infusion bags.

DESCRIPTION OF SYMBOLS 1 Plug body 2 Jig 21 Screw pitch part 22 Holder 23 Press ring

Claims (12)

100 parts by mass of a hydrogenated block copolymer (a),
10 to 50 parts by mass of a polypropylene resin (b),
75 to 200 parts by mass of a non-aromatic softener (d);
1 to 150 parts by mass of an inorganic filler (e),
A thermoplastic elastomer composition comprising:
The hydrogenated block copolymer (a) comprises a polymer block A1 mainly composed of at least one vinyl aromatic hydrocarbon compound monomer unit and a polymer block mainly composed of at least one conjugated diene compound monomer unit. And a hydrogenated hydrogenated block copolymer (a-1),
The hydrogenated block copolymer (a-1) has a weight average molecular weight of 100,000 to 550,000,
The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-1) is more than 20% by mass and 50% by mass or less;
A thermoplastic elastomer composition, wherein the inorganic filler (e) is surface-treated silica. The hydrogenated block copolymer (a) is:
The hydrogenated block copolymer (a-1),
Hydrogenation comprising at least one polymer block A2 mainly composed of a vinyl aromatic hydrocarbon compound monomer unit and at least one polymer block B2 mainly composed of a conjugated diene compound monomer unit A hydrogenated block copolymer (a-2),
The hydrogenated block copolymer (a-2) has a weight average molecular weight of 120,000 to 230,000,
The content of all vinyl aromatic hydrocarbon compound monomer units in the hydrogenated block copolymer (a-2) is 7% by mass or more and 20% by mass or less,
The mass ratio ((a-1) / (a-2)) of the hydrogenated block copolymer (a-1) to the hydrogenated block copolymer (a-2) is 70/30 to 95/5. The thermoplastic elastomer composition according to claim 1, which is present.   3. The thermoplastic resin according to claim 2, wherein in the hydrogenated block copolymer (a-2), the vinyl bond amount in the monomer unit of the conjugated diene compound before hydrogenation is 63 mol% to 95 mol%. 4. Elastomer composition. The hydrogenated block copolymer (a-2) comprises at least two polymer blocks A2 mainly composed of vinyl aromatic hydrocarbon compound monomer units and at least two conjugated diene compound monomer units. And a main polymer block B2,
The at least one polymer block B2 is located at a terminal of the hydrogenated block copolymer (a-2), and the content of the polymer block B2 at the terminal is determined by the hydrogenated block copolymer (a). The thermoplastic elastomer composition according to claim 2 or 3, wherein the content of the thermoplastic elastomer composition is 0.5 to 9% by mass in (2). In the hydrogenated block copolymer (a-1), the vinyl bond amount before hydrogenation in the conjugated diene compound monomer unit is 30 mol% to 60 mol%.
The thermoplastic elastomer composition according to any one of claims 1 to 4. Shore A hardness is 55 or less, needle stick resistance is 4.0 kgf or less,
The thermoplastic elastomer composition according to any one of claims 1 to 5. The inorganic filler (e) is
Surface-treated with a silane coupling agent,
The thermoplastic elastomer composition according to any one of claims 1 to 6.   The thermoplastic elastomer composition according to any one of claims 1 to 7, wherein an odor intensity according to a six-stage odor intensity display method is 3 or less.   A plug comprising the thermoplastic elastomer composition according to claim 1.   A container comprising the plug according to claim 9.   A plug for medical use, comprising the thermoplastic elastomer composition according to any one of claims 1 to 8.   A container for medical use comprising the plug according to claim 11.