Resin composition, stretchable film, sheet, and tube

Abstract

The present invention provides a resin composition containing a hydrogenated block copolymer composition and a polyolefin-based thermoplastic resin C. The hydrogenated block copolymer composition contains a hydrogenated block copolymer A represented by a specific general formula (A) and a hydrogenated block copolymer B represented by a specific general formula (B). The weight ratio of the hydrogenated block copolymer A to the hydrogenated block copolymer B is within a specific range, and the hydrogenation rate of the olefin in the polymer component constituting the hydrogenated block copolymer composition is within a specific range.

Description

Technical Field

[0001] The present invention relates to a resin composition, and more particularly, to a resin composition capable of providing a molded article that achieves both high levels of tensile stress and resilience, has excellent impact resistance, and also has excellent thermal stability. Background Art

[0002] Aromatic vinyl-conjugated diene-aromatic vinyl block copolymers such as styrene-isoprene-styrene block copolymer (SIS) and styrene-butadiene-styrene block copolymer (SBS) are thermoplastic elastomers having characteristic properties in various aspects, and thus are used in various applications. Even among thermoplastic elastomers, aromatic vinyl-conjugated diene-aromatic vinyl block copolymers are used as materials for films, sheets, tubes, etc. that require stretchability because they are particularly stretchy.

[0003] A resin composition containing such an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer can be used as a material for a molded article that requires stretchability, particularly one that achieves both tensile stress and resilience. However, there is a tendency that when one of the properties of tensile stress and resilience is improved, the other property decreases, and there is a so-called trade-off relationship between tensile stress and resilience, so it is required to achieve both. In addition, in order to improve the durability of the molded article, etc., as a resin composition, a resin composition capable of improving the impact resistance and thermal stability of the obtained molded article is required.

[0004] For example, Patent Document 1 discloses a hydrogenated block copolymer having a polymer block (C) mainly composed of a conjugated diene compound, a polymer block (B) mainly composed of a conjugated diene compound, and a polymer block (S) mainly composed of an aromatic vinyl compound in the molecule. The polymer block (B) includes polymer blocks (B1) and (B2). In the hydrogenated block copolymer, the content of the polymer block (C) is 1 to 20% by mass, the content of the polymer block (B) is 73 to 97% by mass, the content of the polymer block (S) is 1 to 15% by mass, the amount of vinyl bonds before hydrogenation of the polymer block (C) is 1 to 25 mol%, the amount of vinyl bonds of the polymer block (B1) is 40 to 60 mol%, the amount of vinyl bonds of the polymer block (B2) is 60 to 100 mol%, and the hydrogenation rate is 80 mol% or more. However, in the technology of Patent Document 1, it is not possible to achieve both high levels of tensile stress and resilience of the obtained molded article. In addition, in the technology of Patent Document 1, the impact resistance of the obtained molded article is insufficient, so improvement of impact resistance is required.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: International Publication No. WO2017 / 188190 SUMMARY OF THE INVENTION

[0008] Problems to be Solved by the Invention

[0009] The present invention has been made in view of such actual circumstances, and an object of the present invention is to provide a resin composition capable of providing a molded article that achieves a high level of both tensile stress and resilience, has excellent impact resistance, and also has excellent thermal stability.

[0010] Means for Solving the Problems

[0011] The inventors of the present invention conducted research to achieve the above object, and as a result, found that a resin composition containing a hydrogenated block copolymer composition and a polyolefin-based thermoplastic resin C can provide a molded article that achieves a high level of both tensile stress and resilience, has excellent impact resistance, and also has excellent thermal stability. The hydrogenated block copolymer composition contains a hydrogenated block copolymer A represented by a specific general formula (A) and a hydrogenated block copolymer B represented by a specific general formula (B), the weight ratio of the hydrogenated block copolymer A to the hydrogenated block copolymer B in the hydrogenated block copolymer composition is within a specific range, and the hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is within a specific range, thereby completing the present invention.

[0012] That is, according to the present invention, there is provided a resin composition containing a hydrogenated block copolymer composition and a polyolefin-based thermoplastic resin C, the hydrogenated block copolymer composition having a hydrogenated block copolymer A represented by the following general formula (A) and a hydrogenated block copolymer B represented by the following general formula (B).

[0013] The weight ratio (A / B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B in the hydrogenated block copolymer composition is 10 / 90 to 80 / 20.

[0014] The hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is 10 to 100%.

[0015] Ar1 a -HD a -Ar2 a (A)

[0016] Ar1 b -HD b -Ar2 b (B)

[0017] (In the above general formula (A) and general formula (B), Ar1 a , Ar2 a , Ar1 b and Ar2b is an aromatic vinyl polymer block, HD a and HD b is a hydrogenated polymer block of a conjugated diene polymer, Ar2 a The weight-average molecular weight (Mw(Ar2 a )) relative to Ar1 a The weight-average molecular weight (Mw(Ar1 a )) ratio (Mw(Ar2 a ) / Mw(Ar1 a )) is 2.6 to 66, Ar2 b The weight-average molecular weight (Mw(Ar2 b )) relative to Ar1 b The weight-average molecular weight (Mw(Ar1 b )) ratio (Mw(Ar2 b ) / Mw(Ar1 b )) is 0.95 to 1.05.)

[0018] In the resin composition of the present invention, it is preferable that the proportion of the aromatic vinyl monomer units in all the repeating units of the polymer components of the above hydrogenated block copolymer composition is 20 to 70% by weight.

[0019] In the resin composition of the present invention, it is preferable that the vinyl bond contents of HD a and HD b in the above general formula (A) and general formula (B) of the above hydrogenated block copolymer composition are respectively 1 to 80 mol%.

[0020] In the resin composition of the present invention, it is preferable that in the above general formula (A) and general formula (B) of the above hydrogenated block copolymer composition, the weight-average molecular weights of Ar1 a , Ar1 b and Ar2 b are respectively in the range of 2000 to 40000, and the weight-average molecular weights of HD a and HD b are respectively in the range of 10000 to 300000.

[0021] In the resin composition of the present invention, it is preferable that the ratio (C / A+B) of the content of the above polyolefin-based thermoplastic resin C to the total content of the above hydrogenated block copolymer A and the above hydrogenated block copolymer B is 10 / 90 to 90 / 10 by weight.

[0022] In the resin composition of the present invention, it is preferable that the weight-average molecular weight of the polymer components constituting the above hydrogenated block copolymer composition as a whole is 30000 to 400000.

[0023] In the resin composition of the present invention, it is preferable that the polyolefin-based thermoplastic resin C is a polypropylene-based resin.

[0024] Furthermore, according to the present invention, a stretchable film, sheet, or tube made of the resin composition described in any one of the above can be provided.

[0025] Advantages of the Invention

[0026] According to the present invention, a resin composition can be provided that can provide a molded article with high levels of both tensile stress and resilience, excellent impact resistance, and excellent thermal stability. Detailed Description of Embodiments

[0027] The resin composition of the present invention contains a hydrogenated block copolymer composition and a polyolefin-based thermoplastic resin C. The hydrogenated block copolymer composition contains a hydrogenated block copolymer A represented by the following general formula (A) and a hydrogenated block copolymer B represented by the following general formula (B).

[0028] The weight ratio (A / B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B in the hydrogenated block copolymer composition is 10 / 90 to 80 / 20.

[0029] The hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is 10 to 100%.

[0030] The hydrogenated block copolymer composition used in the present invention contains a hydrogenated block copolymer A represented by the following general formula (A) and a hydrogenated block copolymer B represented by the following general formula (B).

[0031] Ar1 a -HD a -Ar2 a (A)

[0032] Ar1 b -HD b -Ar2 b (B)

[0033] In the above general formula (A), Ar1 a , Ar2 a are aromatic vinyl polymer blocks, and the ratio of the weight average molecular weight (Mw(Ar2 a )) of Ar2 a to the weight average molecular weight (Mw(Ar1 a )) of Ar1 a (Mw(Ar2 a ) / Mw(Ar1 a )) is 2.6 to 66. Furthermore, HD a is a hydrogenated polymer block of a conjugated diene polymer.

[0034] In addition, in the above general formula (B), Ar1 b , Ar2 b is an aromatic vinyl polymer block, and the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b relative to the weight-average molecular weight (Mw(Ar1 b )) of Ar1 b is in the ratio (Mw(Ar2 b ) / Mw(Ar1 b )) of 0.95 to 1.05. In addition, HD b is a hydrogenated polymer block of a conjugated diene polymer.

[0035] The hydrogenated block copolymer composition used in the present invention is not particularly limited, and it is preferable to contain only the hydrogenated block copolymer A and the hydrogenated block copolymer B as polymer components.

[0036] The aromatic vinyl polymer blocks Ar1 a , Ar2 a , Ar1 b , Ar2 b of the hydrogenated block copolymer A and the hydrogenated block copolymer B are polymer blocks composed of aromatic vinyl monomer units.

[0037] As the aromatic vinyl monomer used for forming the aromatic vinyl monomer unit, as long as it is an aromatic vinyl compound, there is no particular limitation. Examples of the aromatic vinyl compound include: styrene; styrenes substituted with an alkyl group such as α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-tert-butylstyrene, 5-tert-butyl-2-methylstyrene; styrenes substituted with a halogen atom such as 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 4-bromostyrene, 2-methyl-4,6-dichlorostyrene, 2,4-dibromostyrene; vinylnaphthalene and the like. Among these, styrene is preferably used. These aromatic vinyl monomers can be used alone or in combination of two or more in each aromatic vinyl polymer block. In addition, the same aromatic vinyl monomer or different aromatic vinyl monomers can be used in each aromatic vinyl polymer block. The content of the aromatic vinyl monomer unit in each aromatic vinyl polymer block is preferably 80% by weight or more, more preferably 90% by weight or more, and particularly preferably substantially 100% by weight relative to the entire aromatic vinyl polymer block.

[0038] In addition, the aromatic vinyl polymer blocks Ar1 a and Ar2 a in the hydrogenated block copolymer A and the hydrogenated block copolymer B, b and Ar2 b may each contain monomer units other than aromatic vinyl monomer units. Examples of monomers constituting the monomer units other than aromatic vinyl monomer units include: conjugated diene monomers such as 1,3-butadiene and isoprene (2-methyl-1,3-butadiene); α,β-unsaturated nitrile monomers; unsaturated carboxylic acid or acid anhydride monomers; unsaturated carboxylic acid ester monomers; non-conjugated diene monomers, and the like.

[0039] The content of the monomer units other than aromatic vinyl monomer units in each aromatic vinyl polymer block is preferably 20% by weight or less, more preferably 10% by weight or less, and particularly preferably substantially 0% by weight, based on the total amount of the aromatic vinyl polymer block.

[0040] The hydrogenated polymer blocks HD a and HD b of the conjugated diene polymers constituting the hydrogenated block copolymer A and the hydrogenated block copolymer B are polymer blocks composed of conjugated diene monomer units, and at least a part of the conjugated diene monomer units constituting the polymer blocks is hydrogenated.

[0041] The conjugated diene monomer used for constituting the conjugated diene monomer units is not particularly limited as long as it is a conjugated diene compound. Examples of the conjugated diene compound include, for example: 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 2-chloro-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, and the like. From the viewpoint of polymerization reactivity, 1,3-butadiene and / or isoprene is preferably used, and isoprene is particularly preferably used. These conjugated diene monomers can be used alone or in combination of two or more in each hydrogenated polymer block. In addition, the same conjugated diene monomer can be used in each hydrogenated polymer block, or different conjugated diene monomers can also be used. The content of the conjugated diene monomer units (including the hydrogenated conjugated diene monomer units) in each hydrogenated polymer block is preferably 80% by weight or more, more preferably 90% by weight or more, and particularly preferably substantially 100% by weight, based on the total amount of the conjugated diene polymer block.

[0042] The hydrogenated polymer blocks HD a and HD bIt may separately contain monomer units other than conjugated diene monomer units. Examples of the monomers constituting the monomer units other than conjugated diene monomer units include: aromatic vinyl monomers such as styrene and α-methylstyrene; α,β-unsaturated nitrile monomers; unsaturated carboxylic acid or acid anhydride monomers; unsaturated carboxylic acid ester monomers; non-conjugated diene monomers, etc.

[0043] The content of monomer units other than conjugated diene monomer units (including also hydrogenated conjugated diene monomer units) in each hydrogenated polymer block is preferably 20% by weight or less, more preferably 10% by weight or less, and particularly preferably substantially 0% by weight relative to the whole conjugated diene polymer block.

[0044] In the hydrogenated block copolymer A constituting the hydrogenated block copolymer composition, Ar2 a The weight-average molecular weight (Mw(Ar2 a )) relative to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a The ratio (Mw(Ar2 a ) / Mw(Ar1 a )) is in the range of 2.6 to 66. Therefore, the hydrogenated block copolymer A is an asymmetric aromatic vinyl-conjugated diene-aromatic vinyl block copolymer hydride composed of an aromatic vinyl polymer block Ar1 a having a relatively small weight-average molecular weight, a hydrogenated polymer block HD a of a conjugated diene polymer, and an aromatic vinyl polymer block Ar2 a having a relatively large weight-average molecular weight connected in sequence.

[0045] In the hydrogenated block copolymer A, Mw(Ar2 a ) / Mw(Ar1 a ) is in the range of 2.6 to 66. Whether Mw(Ar2 a ) / Mw(Ar1 a ) is too small or too large, it is difficult to balance the tensile stress and the restoring force of the obtained molded body. From the viewpoint of impact resistance, Mw(Ar2 a ) / Mw(Ar1 a ) is preferably in the range of 4 to 40, more preferably in the range of 4.5 to 35. In addition, in the present invention, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polymer and polymer block are values obtained as polystyrene-equivalent values based on the measurement by high performance liquid chromatography.

[0046] In addition, the weight-average molecular weight (Mw(Ar1 a ) of the aromatic vinyl polymer block Ar1 having a relatively small weight-average molecular weight constituting the hydrogenated block copolymer A a of the aromatic vinyl polymer block Ar1 having a relatively small weight-average molecular weight constituting the hydrogenated block copolymer Aa )) Preferably it is 2,000 to 40,000, more preferably 2,500 to 30,000, and still more preferably 3,000 to 10,000. By making Mw(Ar1 a ) within the above range, the tensile stress and recovery force of the obtained molded body can be balanced at a higher level.

[0047] In addition, the aromatic vinyl polymer block Ar2 having a relatively large weight-average molecular weight that constitutes the hydrogenated block copolymer A a has a weight-average molecular weight (Mw(Ar2 a )) preferably of 5,000 to 250,000, more preferably 8,000 to 120,000, and still more preferably 10,000 to 80,000. By making Mw(Ar2 a ) within the above range, the tensile stress and recovery force of the obtained molded body can be balanced at a higher level.

[0048] The hydrogenated polymer block HD of the conjugated diene polymer that constitutes the hydrogenated block copolymer A a has a vinyl bond content (the proportion of 1,2-vinyl bonds and 3,4-vinyl bonds in all conjugated diene monomer units) preferably of 1 to 80 mol%, more preferably 10 to 60 mol%, and still more preferably 20 to 40 mol%. By making the vinyl bond content within the above range, the compatibility between the hydrogenated block copolymer A and the polyolefin-based thermoplastic resin C can be improved, and the tensile stress and recovery force of the obtained molded body can be balanced at a higher level. The vinyl bond content of the hydrogenated polymer block of the conjugated diene polymer can be determined by 1 1H-NMR using deuterated chloroform as a solvent.

[0049] The hydrogenated polymer block HD of the conjugated diene polymer that constitutes the hydrogenated block copolymer A a has a weight-average molecular weight (Mw(HD a )) preferably of 10,000 to 300,000, more preferably 15,000 to 300,000, still more preferably 15,000 to 150,000, and particularly preferably 20,000 to 80,000.

[0050] The content of the aromatic vinyl monomer unit relative to all monomer units of the hydrogenated block copolymer A is not particularly limited, preferably 30 to 95% by weight, more preferably 35 to 90% by weight, still more preferably 40 to 87% by weight, and particularly preferably 43 to 85% by weight. The content of the aromatic vinyl monomer unit relative to all monomer units of the hydrogenated block copolymer A can be determined based on the detection intensity ratio of a differential refractometer and an ultraviolet detector in the measurement by high performance liquid chromatography.

[0051] The weight-average molecular weight of the hydrogenated block copolymer A as a whole is not particularly limited, preferably 20,000 to 500,000, more preferably 25,000 to 300,000, and still more preferably 30,000 to 150,000.

[0052] In addition, the hydrogenated block copolymer B constituting the hydrogenated block copolymer composition is a hydrogenated product of an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer formed by bonding two aromatic vinyl polymer blocks Ar1 b and Ar2 b to both ends of the conjugated diene polymer block HD b respectively. Regarding the weight-average molecular weights (Mw(Ar1 b ), Mw(Ar2 b )) of the two aromatic vinyl polymer blocks Ar1 b and Ar2 b constituting the hydrogenated block copolymer B, the ratio (Mw(Ar2 b )) / Mw(Ar1 b )) of the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b to the weight-average molecular weight (Mw(Ar1 b )) of Ar1 b is 0.95 to 1.05.

[0053] The weight-average molecular weights (Mw(Ar1 b ), Mw(Ar2 b )) of the two aromatic vinyl polymer blocks Ar1 b and Ar2 b constituting the hydrogenated block copolymer B are each preferably 2,000 to 40,000, more preferably 2,500 to 30,000, and still more preferably 3,000 to 10,000. By making Mw(Ar1 b ) and Mw(Ar2 b ) within the above range, the tensile stress and recovery force of the obtained molded body can be balanced at a higher level. The weight-average molecular weights (Mw(Ar1 b ), Mw(Ar2 b )) of the two aromatic vinyl polymer blocks Ar1 b and Ar2 b can be equal to each other or not equal to each other, and are preferably substantially equal. For example, the ratio (Mw(Ar2 b )) / Mw(Ar1 b )) of the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b to the weight-average molecular weight (Mw(Ar1 b )) of Ar1b ) It suffices to be in the range of 0.95 to 1.05, and preferably in the range of 0.97 to 1.03.

[0054] In addition, at least one of the two aromatic vinyl polymer blocks Ar1 b , Ar2 b The weight-average molecular weight (Mw(Ar1 b ), Mw(Ar2 b )) can be equal to or different from the weight-average molecular weight of the aromatic vinyl polymer block Ar1 a having a smaller weight-average molecular weight that constitutes the hydrogenated block copolymer A, a and is preferably substantially equal. For example, the weight-average molecular weight (Mw(Ar1 b )) of Ar1 b relative to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a The ratio (Mw(Ar1 b ) / Mw(Ar1 a )) can be in the range of 0.9 to 2.2, and the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b relative to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a The ratio (Mw(Ar2 b ) / Mw(Ar1 a )) can be in the range of 0.9 to 2.2. In addition, for example, preferably the weight-average molecular weight (Mw(Ar1 b )) of Ar1 b relative to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a The ratio (Mw(Ar1 b ) / Mw(Ar1 a )) is in the range of 0.95 to 1.05 or the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b relative to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a The ratio (Mw(Ar2 b ) / Mw(Ar1 a )) is in the range of 0.95 to 1.05.

[0055] The hydrogenated polymer block HD of the conjugated diene polymer that constitutes the hydrogenated block copolymer B bThe vinyl bond content (the proportion of 1,2-vinyl bonds and 3,4-vinyl bonds in all conjugated diene monomer units) is preferably 1 to 80 mol%, more preferably 10 to 60 mol%, and still more preferably 20 to 40 mol%. By making the vinyl bond content within the above range, the compatibility between the hydrogenated block copolymer B and the polyolefin-based thermoplastic resin C can be improved, and the tensile stress and recovery force of the obtained molded article can be balanced at a higher level. The vinyl bond content of the hydrogenated polymer block of the conjugated diene polymer can be determined by 1 1H-NMR using deuterated chloroform as a solvent. In addition, the vinyl bond content of the hydrogenated polymer block HD b of the conjugated diene polymer constituting the hydrogenated block copolymer B is preferably substantially equal to the vinyl bond content of the hydrogenated polymer block HD a of the conjugated diene polymer constituting the hydrogenated block copolymer A. For example, the ratio of the vinyl bond content of the hydrogenated polymer block HD b of the conjugated diene polymer constituting the hydrogenated block copolymer B to the vinyl bond content of the hydrogenated polymer block HD a of the conjugated diene polymer constituting the hydrogenated block copolymer A is preferably in the range of 0.95 to 1.05.

[0056] In addition, when manufacturing the hydrogenated block copolymer composition used in the present invention, in the case of using a manufacturing method using a coupling agent, such as in the case of using a manufacturing method of a hydrogenated block copolymer composition having the steps (1a) to (6a) described later, the hydrogenated polymer block HD b of the conjugated diene polymer constituting the hydrogenated block copolymer B may contain residues of the coupling agent. Specifically, the hydrogenated block copolymer B may be a compound represented by the following formula.

[0057] Ar1 b -(HD b’ -X-HD b” )-Ar2 b

[0058] That is, as shown in the above formula, the hydrogenated polymer block HD b of the conjugated diene polymer may be in a form in which HD b’ , HD b” are coupled via the residue X of the coupling agent. In addition, as the residue X of the coupling agent, residues of bifunctional coupling agents exemplified in the manufacturing method of the hydrogenated block copolymer composition having the steps (1a) to (6a) described later can be cited.

[0059] The weight-average molecular weight (Mw(HD b of the hydrogenated polymer block HD b)) Preferably it is 10,000 to 300,000, more preferably 15,000 to 300,000, still more preferably 15,000 to 150,000, and particularly preferably 20,000 to 80,000.

[0060] The content of the aromatic vinyl monomer unit relative to all the monomer units of the hydrogenated block copolymer B is not particularly limited, preferably 10 to 35% by weight, more preferably 12 to 32% by weight, and still more preferably 15 to 30% by weight. The content of the aromatic vinyl monomer unit relative to all the monomer units of the hydrogenated block copolymer A can be determined based on the detection intensity ratio of the differential refractometer and the ultraviolet detector in the measurement by high performance liquid chromatography.

[0061] The weight average molecular weight of the hydrogenated block copolymer B as a whole is not particularly limited, preferably 20,000 to 200,000, more preferably 25,000 to 150,000, and still more preferably 30,000 to 70,000.

[0062] The molecular weight distribution represented by the ratio [(Mw) / (Mn)] of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the hydrogenated block copolymer A and the hydrogenated block copolymer B constituting the hydrogenated block copolymer composition used in the present invention, and each polymer block constituting them is not particularly limited, and is preferably 1.1 or less, more preferably 1.05 or less.

[0063] The weight ratio (A / B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B contained in the hydrogenated block copolymer composition used in the present invention is 10 / 90 to 80 / 20. Whether the weight ratio (A / B) is too small or too large, it is difficult to balance the high elastic modulus and the small permanent elongation rate. The weight ratio (A / B) is preferably 12 / 88 to 60 / 40, more preferably 15 / 85 to 50 / 50. By containing the hydrogenated block copolymer A and the hydrogenated block copolymer B at such a ratio, the tensile stress and the recovery force of the obtained molded body can be balanced at a higher level. The weight ratio (A / B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B can be determined based on the area ratio of the peaks corresponding to the respective block copolymers in the chromatogram obtained by high performance liquid chromatography.

[0064] In addition, in the hydrogenated block copolymer composition used in the present invention, the hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is in the range of 10 to 100%. Here, the hydrogenation rate of the olefin refers to the hydrogenation rate of the olefin in all the polymer components constituting the hydrogenated block copolymer composition. Specifically, it refers to the ratio (mol%) of the non-aromatic carbon-carbon double bonds that have been hydrogenated among all the non-aromatic carbon-carbon double bonds contained in the polymer components before hydrogenation. The present inventors have conducted in-depth research and found that, according to a resin composition containing the following hydrogenated block copolymer composition as the hydrogenated block copolymer composition, it is possible to achieve excellent thermal stability while achieving a high elastic modulus and a small permanent elongation rate at a high level, and furthermore, excellent impact resistance can be achieved. The above hydrogenated block copolymer composition contains the hydrogenated block copolymer A represented by the general formula (A) and the hydrogenated block copolymer B represented by the general formula (B) in a specific weight ratio, and the hydrogenation rate of the olefin in the hydrogenated block copolymer composition is in the above range.

[0065] The hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition used in the present invention is in the range of 10 to 100%. When the hydrogenation rate of the olefin is too low, the thermal stability of the resin composition becomes insufficient. The hydrogenation rate of the olefin is preferably 30 to 100%, more preferably 70 to 100%, and further preferably 90 to 100%. By making the hydrogenation rate of the olefin in the above range, it is possible to further improve the thermal stability while maintaining the excellent tensile stress, recovery force, and impact resistance of the obtained molded body. The hydrogenation rate of the olefin can be determined by 1 1H-NMR spectroscopy using deuterated chloroform as a solvent.

[0066] In addition, it is sufficient that the hydrogenation rate of the olefin in the hydrogenated block copolymer composition used in the present invention is in the above range. The iodine value of the polymer components constituting the hydrogenated block copolymer composition is preferably in the range of 0 to 300 gI 2 / 100 g, more preferably in the range of 0 to 150 gI 2 / 100 g, further preferably in the range of 0 to 125 gI 2 / 100 g, even more preferably in the range of 0 to 100 gI 2 / 100 g, particularly preferably in the range of 0 to 75 gI 2 / 100 g, and most preferably in the range of 0 to 30 gI 2 / 100 g. By making the iodine value in the above range, it is possible to further improve the thermal stability while maintaining the excellent tensile stress, recovery force, and impact resistance of the obtained molded body. The iodine value can be determined based on JIS K0070.

[0067] In the hydrogenated block copolymer composition used in the present invention, the proportion of the aromatic vinyl monomer unit relative to the entire polymer component (all monomer units constituting the polymer component) in the hydrogenated block copolymer composition (hereinafter sometimes referred to as "the overall aromatic vinyl monomer unit content") is preferably 20 to 70% by weight, more preferably 25 to 60% by weight, and still more preferably 30 to 50% by weight. By making the overall aromatic vinyl monomer unit content within the above range, the tensile stress and recovery force of the obtained molded body can be balanced at a higher level. The overall aromatic vinyl monomer unit content can be easily adjusted by considering the aromatic vinyl monomer unit contents of the hydrogenated block copolymer A, the hydrogenated block copolymer B, and the polymer components other than them constituting the hydrogenated block copolymer composition and adjusting their blending amounts. The overall aromatic vinyl monomer unit content can be determined by 1 1H-NMR measurement using deuterated chloroform as a solvent.

[0068] In addition, when all the polymer components constituting the hydrogenated block copolymer composition are composed only of aromatic vinyl monomer units and conjugated diene monomer units, the polymer components in the hydrogenated block copolymer composition can be ozonized according to the method described in Rubber Chem. Technol., 45, 1295 (1972), and then reduced with lithium aluminum hydride, whereby the conjugated diene monomer unit part (including the hydrogenated part) can be decomposed and only the aromatic vinyl monomer unit part can be taken out, so that the overall aromatic vinyl monomer unit content can be easily measured. By the same method, the aromatic vinyl monomer unit content and the conjugated diene monomer unit content in each block copolymer can be determined.

[0069] There is no particular limitation on the weight average molecular weight of the entire polymer component constituting the hydrogenated block copolymer composition used in the present invention, and it is preferably 30,000 to 400,000, more preferably 35,000 to 100,000, and still more preferably 40,000 to 80,000.

[0070] Furthermore, there is no particular limitation on the molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the entire polymer component constituting the hydrogenated block copolymer composition used in the present invention, and it is preferably 1.01 to 10, more preferably 1.02 to 5, and still more preferably 1.03 to 3.

[0071] In addition, the melt index of the hydrogenated block copolymer composition used in the present invention is preferably 0.1 to 150 g / 10 min, more preferably 3 to 100 g / 10 min, and further preferably 5 to 50 g / 10 min. The melt index of the hydrogenated block copolymer composition can be measured according to ASTM D-1238 (condition G, 200 °C, 5 kg).

[0072] As a method for producing the hydrogenated block copolymer composition used in the present invention, there is no particular limitation, and it can be produced, for example, as follows: The hydrogenated block copolymer A and the hydrogenated block copolymer B are separately produced according to the existing production methods of block copolymers and hydrogenation methods, and on the basis of optionally blending other polymer components and various additives, they are mixed by conventional methods such as kneading and solution mixing. On the other hand, in the present invention, from the viewpoint of being able to produce the hydrogenated block copolymer composition with high productivity, the production method described below is preferred.

[0073] That is, the production method of the hydrogenated block copolymer composition used in the present invention is preferably a production method having the following steps (1) to (7).

[0074] (1): A step of polymerizing an aromatic vinyl monomer in a solvent using a polymerization initiator to obtain a solution containing an aromatic vinyl polymer having a reactive end.

[0075] (2): A step of adding a conjugated diene monomer to the solution containing the aromatic vinyl polymer having a reactive end obtained in the step (1) and polymerizing the conjugated diene monomer to obtain a solution containing an aromatic vinyl-conjugated diene block copolymer having a reactive end.

[0076] (3): A step of adding an aromatic vinyl monomer to the solution containing the aromatic vinyl-conjugated diene block copolymer having a reactive end obtained in the step (2) and polymerizing the aromatic vinyl monomer to obtain a solution containing an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having a reactive end.

[0077] (4): A step of adding a polymerization terminator in an amount less than 1 molar equivalent relative to the reactive end to the solution containing the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having a reactive end obtained in the step (3) to inactivate a part of the reactive ends of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having a reactive end, and obtaining a solution containing block copolymer B'.

[0078] (5): A step of adding an aromatic vinyl monomer to the solution containing the block copolymer B’ obtained in the above step (4) and polymerizing the aromatic vinyl monomer to obtain a solution containing the block copolymer B’ and the block copolymer A’.

[0079] (6): A step of subjecting the solution containing the block copolymer B’ and the block copolymer A’ obtained in the above step (5) to a hydrogenation reaction to obtain a solution containing the hydrogenated block copolymer B and the hydrogenated block copolymer A.

[0080] (7): A step of recovering the hydrogenated block copolymer composition from the solution containing the hydrogenated block copolymer B and the hydrogenated block copolymer A obtained in the above step (6).

[0081] <Step (1)>

[0082] In the method for producing the hydrogenated block copolymer composition, first, in step (1), an aromatic vinyl monomer is polymerized using a polymerization initiator in a solvent to obtain a solution containing an aromatic vinyl polymer having a reactive terminal.

[0083] As the polymerization initiator, a polymerization initiator known to have anionic polymerization activity for aromatic vinyl monomers and conjugated diene monomers can be used. Examples of the polymerization initiator include organic alkali metal compounds, organic alkaline earth metal compounds, and organic lanthanide rare earth metal compounds.

[0084] As the organic alkali metal compound, an organic lithium compound having one or more lithium atoms in the molecule is particularly preferably used. Specific examples of the organic alkali metal compound include: organic monolithium compounds such as ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, hexyl lithium, phenyl lithium, stilbene lithium, dialkylamino lithium, diphenylamino lithium, and bis(trimethylsilyl)amino lithium; organic dilithium compounds such as methylene dilithium, tetramethylene dilithium, hexamethylene dilithium, isoprene dilithium, and 1,4-dilithioethylcyclohexane; and organic trilithium compounds such as 1,3,5-trilithiobenzene. Among these, organic monolithium compounds are particularly preferably used.

[0085] Examples of the organic alkaline earth metal compound include n-butylmagnesium bromide, n-hexylmagnesium bromide, calcium ethoxide, calcium stearate, strontium tert-butoxide, barium ethoxide, barium isopropoxide, barium ethyl mercaptide, barium tert-butoxide, barium phenoxide, barium diethylamide, barium stearate, and barium ethyl.

[0086] In addition, in addition to the above, it is also possible to use: a composite catalyst formed from a lanthanide rare earth metal compound containing neodymium, samarium, gadolinium, etc., an alkylaluminum, an alkylaluminum halide, an alkylaluminum hydride; a metallocene-type catalyst containing titanium, vanadium, samarium, gadolinium, etc., etc. catalysts that are homogeneous systems in organic solvents and have living polymerizability.

[0087] The above polymerization initiator can be used alone or in combination of two or more. The amount of the polymerization initiator used can be determined according to the molecular weight of each target block copolymer, and there is no particular limitation. Preferably, it is 0.01 to 20 mmol, more preferably 0.05 to 15 mmol, and still more preferably 0.1 to 10 mmol relative to 100 g of all monomers used for polymerization.

[0088] The solvent for polymerization only needs to be a solvent that is inactive with respect to the polymerization initiator, and there is no particular limitation. Examples thereof include chain hydrocarbon solvents, cyclic hydrocarbon solvents, or a mixed solvent thereof. As the chain hydrocarbon solvent, for example, linear alkanes and olefins having 4 to 6 carbon atoms such as n-butane, isobutane, 1-butene, isobutene, trans-2-butene, cis-2-butene, 1-pentene, trans-2-pentene, cis-2-pentene, n-pentane, isopentane, neopentane, n-hexane, etc. In addition, as the cyclic hydrocarbon solvent, for example: aromatic compounds such as benzene, toluene, xylene, etc.; alicyclic hydrocarbon compounds such as cyclopentane, cyclohexane, etc. These solvents can be used alone or in combination of two or more.

[0089] The amount of the solvent used is not particularly limited, and preferably an amount such that the concentration of all block copolymers in the solution after the polymerization reaction is 5 to 60% by weight, more preferably an amount such that the above concentration is 10 to 55% by weight, and still more preferably an amount such that the above concentration is 20 to 50% by weight.

[0090] In addition, when manufacturing a hydrogenated block copolymer composition, in order to control the structure of each polymer block of each block copolymer, a Lewis base compound can be added to the reaction system. Examples of the Lewis base compound include: ethers such as tetrahydrofuran, diethyl ether, dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, etc.; tertiary amines such as tetramethylethylenediamine, trimethylamine, triethylamine, pyridine, quinuclidine, etc.; alkali metal alcoholates such as potassium tert-pentoxide, potassium tert-butoxide, etc.; phosphines such as triphenylphosphine, etc. These Lewis base compounds can be used alone or in combination of two or more. The above polymerization initiator can be used alone or in combination of two or more. The amount of the polymerization initiator used can be determined according to the molecular weight of each target block copolymer, and there is no particular limitation. Preferably, it is 0.01 to 20 mmol, more preferably 0.05 to 15 mmol, and still more preferably 0.1 to 10 mmol relative to 100 g of all monomers used for polymerization.

[0091] When producing a hydrogenated block copolymer composition, the timing of adding a Lewis base compound is not particularly limited and can be appropriately determined according to the structure of each target block copolymer. For example, it can be added in advance before the initiation of polymerization, or it can be added after polymerizing a part of the polymer block. Further, it can be added in advance before the initiation of polymerization, and at the same time, it can be further added additionally after polymerizing a part of the polymer block.

[0092] The polymerization reaction temperature is preferably 10 to 150 °C, more preferably 30 to 130 °C, and further preferably 40 to 90 °C. The polymerization time is preferably within 48 hours, more preferably 0.5 to 10 hours. In addition, the polymerization pressure can be within the range of the pressure sufficient to maintain the monomers and solvents in the liquid phase at the polymerization temperature, and there is no particular limitation.

[0093] Under the above conditions, using a polymerization initiator in a solvent to polymerize an aromatic vinyl monomer, a solution containing an aromatic vinyl polymer having a reactive end can be obtained. In this way, the aromatic vinyl polymer having a reactive end obtained in step (1) constitutes Ar1 a and constitutes Ar1 b Ar2 b any one of them (i.e., Ar1 b or Ar2 b ). The above Ar1 a is an aromatic vinyl polymer block having a relatively small weight-average molecular weight of the hydrogenated block copolymer A constituting the hydrogenated block copolymer composition, and Ar1 b Ar2 b is an aromatic vinyl polymer block of the hydrogenated block copolymer B. Therefore, each polymerization condition including the amount of the aromatic vinyl monomer in step (1) can be determined according to the target weight-average molecular weight of these polymer blocks, etc.

[0094] <Step (2)>

[0095] Next, in step (2), a conjugated diene monomer is added to the solution containing the aromatic vinyl polymer having a reactive end obtained in the above step (1), and the conjugated diene monomer is polymerized to obtain a solution containing an aromatic vinyl-conjugated diene block copolymer having a reactive end.

[0096] According to step (2), a conjugated diene monomer is added to the solution containing the aromatic vinyl polymer having a reactive end obtained in the above step (1), thereby forming a conjugated diene polymer chain starting from the reactive end, and a solution containing an aromatic vinyl-conjugated diene block copolymer having a reactive end can be obtained.

[0097] The conjugated diene polymer chains formed in step (2) (which constitute the conjugated diene block of the aromatic vinyl-conjugated diene block copolymer with a living end obtained in step (2)) constitute the hydrogenated polymer block HD of the conjugated diene polymer of the hydrogenated block copolymer A a and the hydrogenated polymer block HD of the conjugated diene polymer of the hydrogenated block copolymer B b . Therefore, each polymerization condition including the amount of the conjugated diene polymer in step (2) can be determined according to the target weight-average molecular weight of these polymer blocks, etc. (for example, the polymerization conditions can be determined within the range described in step (1) above).

[0098] <Process (3)>

[0099] Next, in step (3), an aromatic vinyl monomer is added to the solution containing the aromatic vinyl-conjugated diene block copolymer with a living end obtained in step (2) above, and the aromatic vinyl monomer is polymerized to obtain a solution containing an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer with a living end

[0100] According to step (3), an aromatic vinyl monomer is added to the solution containing the aromatic vinyl-conjugated diene block copolymer with a living end obtained in step (2) above, whereby an aromatic vinyl polymer chain is formed starting from the living end, and a solution containing an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer with a living end can be obtained

[0101] The aromatic vinyl polymer chain formed in step (3) (which constitutes the aromatic vinyl block of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer with a living end obtained in step (3)) constitutes one of the aromatic vinyl polymer blocks Ar1 b , Ar2 b of the hydrogenated block copolymer B (that is, one of Ar1 b or Ar2 b that is different from the block formed in step (1). For example, when Ar1 b is formed in step (1), it is Ar2 b ). Therefore, each polymerization condition including the amount of the aromatic vinyl monomer in step (3) can be determined according to the target weight-average molecular weight of such a polymer block, etc. (for example, the polymerization conditions can be determined within the range described in step (1) above).

[0102] <Process (4)>

[0103] Next, in step (4), a polymerization terminator is added in an amount less than 1 molar equivalent relative to the active terminal in the solution containing the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active terminal, so that a part of the active terminals of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active terminal are inactivated, and a solution containing block copolymer B' is obtained.

[0104] The block copolymer B' obtained in step (4) becomes the block copolymer before hydrogenation for obtaining the hydrogenated block copolymer B.

[0105] The polymerization terminator is a polymerization terminator that can react with the active terminal to inactivate the active terminal and does not react with other active terminals after reacting with one active terminal, and there is no particular limitation. Compounds not containing a halogen atom are preferred, and polymerization terminators that generate metal alkoxides, metal aryloxides or metal hydroxides when reacting with the active terminal are particularly preferred. Specific examples of the polymerization terminator include: water; monohydric alcohols such as methanol and ethanol; monohydric phenols such as phenol and cresol.

[0106] The amount of the polymerization terminator used may be determined according to the ratio of the hydrogenated block copolymer A to the hydrogenated block copolymer B constituting the hydrogenated block copolymer composition. As long as it is an amount less than 1 molar equivalent relative to the active terminal of the polymer, there is no particular limitation. The amount of the polymerization terminator used is preferably in the range of 0.18 to 0.91 molar equivalent, more preferably in the range of 0.35 to 0.80 molar equivalent, relative to the active terminal of the polymer.

[0107] In this way, according to step (4), a polymerization terminator is added in an amount less than 1 molar equivalent relative to the active terminal in the solution containing the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active terminal, whereby a part of the active terminals of the copolymer in the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active terminal are inactivated, and the copolymer with the inactivated active terminal becomes the block copolymer B' before hydrogenation for constituting the hydrogenated block copolymer B. Then, the remaining part of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active terminal that does not react with the polymerization terminator remains in the solution in an unreacted state maintaining the active terminal.

[0108] <Step (5)>

[0109] Next, in step (5), an aromatic vinyl monomer is added to the solution containing block copolymer B' obtained in the above step (4), and the aromatic vinyl monomer is polymerized, whereby a solution containing block copolymer B' and block copolymer A' is obtained.

[0110] According to step (5), when an aromatic vinyl monomer is added to the solution obtained in the above step (4), polymerization of the aromatic vinyl monomer further proceeds starting from the aromatic vinyl polymer chain on the active end side of the aromatic vinyl-conjugated diene-aromatic vinyl block copolymer having an active end that remains without reacting with the polymerization terminator, and the aromatic vinyl polymer chain is extended, whereby block copolymer A' is obtained. In addition, block copolymer A' is an aromatic vinyl-conjugated diene-aromatic vinyl block copolymer obtained by extending the aromatic vinyl polymer chain, and becomes the block copolymer before hydrogenation for obtaining hydrogenated block copolymer A.

[0111] At this time, in step (5), the extended aromatic vinyl polymer chain constitutes the aromatic vinyl polymer block Ar2 having a relatively large weight-average molecular weight of the hydrogenated block copolymer A that constitutes the hydrogenated block copolymer composition. a . Therefore, each polymerization condition including the amount of the aromatic vinyl monomer in step (5) may be determined according to the target weight-average molecular weight, etc. of such aromatic vinyl polymer block Ar2 (for example, the polymerization conditions may be determined within the range described in the above step (1)). a

[0112] <Process (6)>

[0113] Next, in step (6), a hydrogenation reaction is carried out on the solution containing block copolymer B' and block copolymer A' obtained in the above step (5), whereby a solution containing hydrogenated block copolymer B and hydrogenated block copolymer A is obtained.

[0114] The method for carrying out the hydrogenation reaction on the solution containing block copolymer B' and block copolymer A' is not particularly limited, and examples thereof include a method of bringing the solution containing block copolymer B' and block copolymer A' into contact with hydrogen in the presence of a hydrogenation catalyst.

[0115] The hydrogenation catalyst is not particularly limited, and examples thereof include: supported heterogeneous catalysts in which metals such as Ni, Pt, Pd, and Ru are supported on carriers such as carbon, silica, alumina, and diatomaceous earth; Ziegler catalysts using organic salts or acetylacetonates of Ni, Co, Fe, Cr, etc. and reducing agents such as organic Al; organometallic compound-based organometallic complex catalysts such as Ru and Rh; homogeneous catalysts in which organolithium, organoaluminum, organomagnesium, etc. are used as reducing agents in metallocene compounds. Among these, Ziegler catalysts are preferred.

[0116] The hydrogenation reaction can be carried out according to the methods disclosed in, for example, Japanese Patent Publication No. Sho 42-8704, Japanese Patent Publication No. Sho 43-6636, Japanese Patent Laid-Open No. Sho 59-133203, Japanese Patent Laid-Open No. Sho 60-220147, etc.

[0117] The conditions of the hydrogenation reaction can be selected according to the hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition. The hydrogenation reaction temperature is preferably 0 to 200 °C, more preferably 30 to 150 °C. In addition, the pressure of hydrogen used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, further preferably 0.3 to 5 MPa, and the hydrogenation reaction time is preferably 3 minutes to 10 hours, more preferably 10 minutes to 5 hours. Additionally, the hydrogenation reaction can be any one of a batch process, a continuous process, or a combination thereof.

[0118] <Step (7)>

[0119] Next, in step (7), the target hydrogenated block copolymer composition is recovered from the solution containing the hydrogenated block copolymer B and the hydrogenated block copolymer A obtained in the above step (6).

[0120] The recovery method can be a conventional method and is not particularly limited. For example, after the reaction is terminated, a polymerization terminator is added as needed to deactivate the active ends of the polymers with active ends, and further additives such as antioxidants are added as needed, and then a known solvent method such as direct drying or stripping is applied to the solution, whereby the target hydrogenated block copolymer composition can be recovered. Additionally, at this time, the above-mentioned polymerization terminator can be used as the polymerization terminator.

[0121] In the case where the hydrogenated block copolymer composition is recovered as a slurry by stripping or the like, dehydration is preferably carried out using any dehydrator such as an extruder press to recover the hydrogenated block copolymer composition in a pellet form, and then the obtained pellets are dried using any dryer such as a belt dryer or an expansion extrusion dryer. In addition, the hydrogenated block copolymer composition obtained in this way can be processed into a granular form or the like by a conventional method and then used.

[0122] The solid (granular, pellet-like, etc.) hydrogenated block copolymer composition obtained in this way is preferably dried using a dryer such as a hopper dryer, a hot air circulation tray dryer, a vacuum tray dryer, or a stirring type vacuum dryer to reduce the water content contained in the solid hydrogenated block copolymer composition and then used. The drying conditions at this time are not particularly limited as long as the target water content can be achieved, and can be set according to the water content to be reduced, the type of dryer, etc., and are usually set in the range of a drying temperature of 40 to 90 °C and a drying time of 1 to 24 hours.

[0123] According to the method for producing the hydrogenated block copolymer composition described above, the hydrogenated block copolymer A and the hydrogenated block copolymer B can be continuously obtained in the same reaction vessel. Therefore, compared with the case where each hydrogenated block copolymer is separately produced and then mixed, the target hydrogenated block copolymer composition can be obtained with excellent productivity.

[0124] In addition, when producing the hydrogenated block copolymer composition of the present invention, in addition to the above-described preferred production method (the production method having steps (1) to (7)), a production method of a hydrogenated block copolymer composition having the following steps (1a) to (6a) is also preferably used.

[0125] (1a): A step of polymerizing an aromatic vinyl monomer using a polymerization initiator in a solvent to obtain a solution containing an aromatic vinyl polymer having a reactive terminal.

[0126] (2a): A step of adding a conjugated diene monomer to the solution containing the aromatic vinyl polymer having a reactive terminal obtained in the step (1a) and polymerizing the conjugated diene monomer to obtain a solution containing an aromatic vinyl-conjugated diene block copolymer having a reactive terminal.

[0127] (3a): A step of adding a difunctional coupling agent to the solution containing the aromatic vinyl-conjugated diene block copolymer having a reactive terminal obtained in the step (2a) in an amount such that the total amount of functional groups is less than 1 molar equivalent relative to the reactive terminal, and coupling a part of the aromatic vinyl-conjugated diene block copolymer having a reactive terminal to obtain a solution containing block copolymer B'.

[0128] (4a): A step of adding an aromatic vinyl monomer to the solution containing block copolymer B' obtained in the step (3a) and polymerizing the aromatic vinyl monomer to obtain a solution containing block copolymer B' and block copolymer A'.

[0129] (5a): A step of subjecting the solution containing block copolymer B' and block copolymer A' obtained in the step (4a) to a hydrogenation reaction to obtain a solution containing hydrogenated block copolymer B and hydrogenated block copolymer A.

[0130] (6a): A step of recovering the hydrogenated block copolymer composition from the solution containing hydrogenated block copolymer B and hydrogenated block copolymer A obtained in the step (5a).

[0131] <Step (1a), Step (2a)>

[0132] Step (1a) and Step (2a) are the same as the above-described steps (1) and (2), and the same conditions can be adopted.

[0133] <Process (3a)>

[0134] In process (3a), in the solution containing the aromatic vinyl-conjugated diene block copolymer having a reactive end obtained in the above process (2a), a difunctional coupling agent is added in an amount such that the total amount of functional groups is less than 1 molar equivalent relative to the reactive end, and a part of the aromatic vinyl-conjugated diene block copolymer having a reactive end is coupled to obtain a solution containing block copolymer B'.

[0135] The block copolymer B' obtained in process (3a) is the block copolymer before hydrogenation for obtaining the hydrogenated block copolymer B.

[0136] As the difunctional coupling agent, as long as it is a coupling agent having two functional groups reactive with the reactive end, there is no particular limitation, and examples thereof include: difunctional halogenated silanes such as dichlorosilane, monomethyldichlorosilane, and dimethyldichlorosilane; difunctional halogenated alkanes such as dichloroethane, dibromoethane, dichloromethane, and dibromomethane; and difunctional tin halides such as stannous dichloride, monomethyldichlorostannane, dimethyldichlorostannane, monoethyldichlorostannane, diethyldichlorostannane, monobutyldichlorostannane, and dibutyldichlorostannane.

[0137] The amount of the difunctional coupling agent used may be determined according to the ratio of the hydrogenated block copolymer A to the hydrogenated block copolymer B constituting the hydrogenated block copolymer composition.

[0138] Thus, according to process (3a), in the solution containing the aromatic vinyl-conjugated diene block copolymer having a reactive end, a difunctional coupling agent is added in an amount such that the total amount of functional groups is less than 1 molar equivalent relative to the reactive end, whereby a part of the copolymer in the aromatic vinyl-conjugated diene block copolymer having a reactive end is coupled to become the block copolymer B' before hydrogenation for constituting the hydrogenated block copolymer B. Then, a part of the remaining aromatic vinyl-conjugated diene block copolymer having a reactive end that does not react with the difunctional coupling agent remains in the solution in an unreacted state maintaining the reactive end.

[0139] <Process (4a)>

[0140] Next, in process (4a), an aromatic vinyl monomer is added to the solution containing block copolymer B' obtained in the above process (3a), and the aromatic vinyl monomer is polymerized to obtain a solution containing block copolymer B' and block copolymer A'.

[0141] According to step (4a), when an aromatic vinyl monomer is added to the solution obtained in the above step (3a), starting from the active end of the aromatic vinyl-conjugated diene block copolymer having an active end that does not react with the bifunctional coupling agent and remains, the aromatic vinyl monomer polymerizes to form an aromatic vinyl polymer chain, whereby block copolymer A' is obtained. In addition, block copolymer A' becomes the block copolymer before hydrogenation for obtaining hydrogenated block copolymer A.

[0142] At this time, in step (4a), the formed aromatic vinyl polymer chain constitutes the aromatic vinyl polymer block Ar2 having a relatively large weight-average molecular weight of the hydrogenated block copolymer A that constitutes the hydrogenated block copolymer composition. a . Therefore, each polymerization condition including the amount of the aromatic vinyl monomer in step (4a) can be determined according to the target weight-average molecular weight, etc. of such an aromatic vinyl polymer block Ar2 a (for example, the polymerization conditions can be determined within the range described in the above step (1)).

[0143] <Process (5a), Process (6a)>

[0144] Then, using the solution containing block copolymer B' and block copolymer A' obtained through step (4a), through the operations in the above steps (5a) and (6a), the hydrogenated block copolymer composition used in the present invention can be obtained. In addition, the above steps (5a) and (6a) are the same as the above steps (6) and (7), and the same conditions can be adopted.

[0145] The resin composition of the present invention contains, in addition to the above hydrogenated block copolymer composition, a polyolefin-based thermoplastic resin C.

[0146] As the polyolefin-based thermoplastic resin C used in the present invention, as long as it is a resin having thermoplasticity with an olefin as the main repeating unit, there is no particular limitation, and it can be any one of a homopolymer of an α-olefin, a copolymer of two or more α-olefins, and a copolymer of an α-olefin and a monomer other than the α-olefin. In addition, it can also be a substance obtained by modifying these (copolymers) polymers. As the polyolefin-based thermoplastic resin C, a polyolefin-based thermoplastic resin substantially free of aromatic vinyl polymer units is preferred. In addition, as the polyolefin-based thermoplastic resin C, the content of the α-olefin unit is preferably 90% by weight or more, more preferably 95% by weight or more, and further preferably substantially 100% by weight.

[0147] As the polyolefin-based thermoplastic resin C used in the present invention, examples include: homopolymers or copolymers of α-olefins such as ethylene and propylene, for example, linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), metallocene polyethylene, etc. polyethylene, polypropylene, metallocene polypropylene, polymethylpentene, polybutene and other α-olefin homopolymers; copolymers of ethylene and other α-olefins, such as ethylene-propylene random copolymers, ethylene-propylene block copolymers, ethylene-butene-1 copolymers, ethylene-propylene-butene-1 copolymers and ethylene-cyclic olefin copolymers; copolymers of α-olefins with unsaturated carboxylic alcohols and their saponified products, such as ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers; copolymers of α-olefins with α,β-unsaturated carboxylic acid esters or α,β-unsaturated carboxylic acids, etc., such as ethylene-α,β-unsaturated carboxylic acid ester copolymers (ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, etc.), ethylene-α,β-unsaturated carboxylic acid copolymers (ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, etc.); acid-modified olefin resins obtained by modifying α-olefin (copolymer) polymers such as polyethylene and polypropylene with unsaturated carboxylic acids and / or their anhydrides such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, etc.; ionomer resins obtained by reacting copolymers of ethylene and methacrylic acid with Na ions or Zn ions, etc.; mixtures thereof. Among these, polypropylene-based resins (that is, homopolymers of propylene or copolymers of propylene and other α-olefins as the main component) are preferred, and homopolymers of propylene or copolymers of propylene and ethylene as the main component are more preferred. As the polypropylene-based resin, the content of propylene units is preferably 50% by weight or more, and more preferably 75% by weight or more. In addition, the polyolefin-based thermoplastic resin C can be used alone or in combination of two or more.

[0148] As the polyolefin-based thermoplastic resin C, specifically, it is possible to use the trade name "Vistamaxx 6102" (manufactured by ExxonMobil Corporation, propylene-ethylene copolymer containing propylene units as the main component, ethylene content 16%, MFR 3 g / 10 min (230 °C, 2.16 kg ASTM D1238), density 0.862 g / cm 3 )), trade name "PT-100" (manufactured by LCY CHEMICAL Corporation), homopolypropylene, MFR 1.6 g / 10 min (230 °C, 21.6 N), melting point 164 °C, propylene content 100 mol%) and the like.

[0149] The weight-average molecular weight of the polyolefin-based thermoplastic resin C is not particularly limited, and is usually selected in the range of 10,000 to 5,000,000, preferably in the range of 50,000 to 800,000.

[0150] The density of the polyolefin-based thermoplastic resin C is usually selected within the range of 0.80 to 0.95 g / cm 3 and preferably within the range of 0.85 to 0.94 g / cm 3 .

[0151] The melt index of the polyolefin-based thermoplastic resin C, as a value measured according to ASTM D-1238 (condition G, 200 °C, 5 kg), is usually selected within the range of 1 to 1000 g / 10 minutes, and preferably within the range of 3 to 500 g / 10 minutes.

[0152] In the resin composition of the present invention, the ratio (C / A+B) of the content of the polyolefin-based thermoplastic resin C to the total content of the hydrogenated block copolymer A and the hydrogenated block copolymer B is preferably 10 / 90 to 90 / 10, more preferably 30 / 70 to 85 / 15, and further preferably 50 / 50 to 80 / 20 by weight ratio. By making the ratio of this content within this range, it is possible to more evenly improve the tensile stress, resilience, and impact resistance of the obtained molded article.

[0153] The resin composition of the present invention may also contain, as needed, antioxidants, tackifying resins, softeners, antibacterial agents, light stabilizers, ultraviolet absorbers, dyes, lubricants, etc.

[0154] In addition to the hydrogenated block copolymer composition and the polyolefin-based thermoplastic resin C, the resin composition of the present invention can also contain antioxidants as needed. The type thereof is not particularly limited, and for example, hindered phenol compounds such as pentaerythritol tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,6-di-tert-butyl-p-cresol, and di-tert-butyl-4-methylphenol can be used; thiodicarboxylates such as dilauryl thiodipropionate; phosphites such as tris(nonylphenyl)phosphite, etc. The amount of the antioxidant used is not particularly limited, and is usually 10 parts by weight or less, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the hydrogenated block copolymer composition. In addition, the antioxidant can be used alone or in combination of two or more. Furthermore, the timing of adding the antioxidant to the resin composition is not particularly limited. For example, it can be added in advance to the hydrogenated block copolymer composition used to form the resin composition, or it can be added when mixing the hydrogenated block copolymer composition and the polyolefin-based thermoplastic resin C.

[0155] Within the range that does not impair the effects of the present invention, the resin composition of the present invention may also contain polymer components other than the hydrogenated block copolymer A, the hydrogenated block copolymer B, and the polyolefin-based thermoplastic resin C.

[0156] As the polymer components other than the hydrogenated block copolymer A, hydrogenated block copolymer B, and polyolefin-based thermoplastic resin C that can be contained in the resin composition of the present invention, for example, can be cited: aromatic vinyl-conjugated diene-aromatic vinyl block copolymers other than the hydrogenated block copolymer A and hydrogenated block copolymer B, aromatic vinyl-conjugated diene block copolymers, aromatic vinyl homopolymers, conjugated diene homopolymers, aromatic vinyl-conjugated diene random copolymers, and their branched polymers; thermoplastic elastomers such as polyurethane-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, and polyester-based thermoplastic elastomers; thermoplastic resins such as polyvinyl chloride, acrylonitrile-styrene copolymers, acrylonitrile-butadiene-styrene copolymers, and polyphenylene ethers, etc.

[0157] In the resin composition of the present invention, the content of the polymer components other than the hydrogenated block copolymer A, hydrogenated block copolymer B, and polyolefin-based thermoplastic resin C is preferably 20% by weight or less, more preferably 10% by weight or less, further preferably 5% by weight or less, particularly preferably 1% by weight or less, and most preferably substantially 0% by weight, relative to the total polymer components.

[0158] The resin composition of the present invention can be produced, for example, by a method of mixing a block copolymer composition, a polyolefin-based thermoplastic resin C, and various additives used as needed. As the method of mixing these components, there is no particular limitation, and examples thereof include: a method of heat-melting and mixing the components using a Banbury mixer, kneader, Labo Plastomill, single-screw extruder, twin-screw extruder, or other kneading devices; a method of dissolving the components in a solvent, uniformly mixing them, and then removing the solvent by heating or the like. Among these, from the viewpoint of more effectively performing the mixing, a method of heat-melting and mixing is preferred. In addition, the temperature during heat-melting and mixing is not particularly limited and generally ranges from 100 to 250 °C.

[0159] The resin composition of the present invention can be used as a molded article. The molded article obtained using the resin composition of the present invention has high levels of both tensile stress and resilience, excellent impact resistance, and excellent thermal stability, and thus can be used for various applications requiring stretchability, impact resistance, and thermal stability.

[0160] The resin composition of the present invention can be used, for example, in the following applications: packaging films and packaging containers for packaging clothes, food, daily necessities, industrial materials, etc.; various rolls for gloves, elastic bands, condoms, OA equipment, office use, etc.; molding materials for anti-vibration sheets, anti-vibration rubbers, impact-absorbing sheets, impact-absorbing films / sheets, residential shock-absorbing sheets, shock-absorbing damping materials, etc. for electronic and electrical equipment; elastic fibers for clothes, sports goods, etc.; various pipe materials, etc.

[0161] The molded article obtained using the resin composition of the present invention contains the above-mentioned hydrogenated block copolymer A, hydrogenated block copolymer B, and polyolefin-based thermoplastic resin C. The content ratios of these components in the molded article are the same as those in the resin composition, and the preferred ranges are also the same.

[0162] The resin composition of the present invention is not particularly limited and can be molded by, for example, an extrusion molding method, an injection molding method, a casting molding method, etc.

[0163] By molding the resin composition of the present invention by an extrusion molding method, molded articles of various shapes such as films, sheets, and tubes can be obtained. As the extrusion molding method, any molding method can be used as long as the resin composition of the present invention is heated to melt the thermoplastic polymer components contained in the resin composition of the present invention and then extruded from an extruder, and there is no particular limitation. It can be a blow molding method in which air is blown into the extruded resin composition.

[0164] As the molding temperature when molding the resin composition by an extrusion molding method, as the temperature of the resin composition, it is preferably 255 °C or lower, more preferably 250 °C or lower. The lower limit of the molding temperature is only required to be a temperature at which the thermoplastic polymer components contained in the resin composition can be melted, for example, 200 °C or higher. By setting the molding temperature within the above range, a molded article with excellent homogeneity and shape uniformity can be obtained.

[0165] The extruder used in the extrusion molding method is not particularly limited, and a single-screw extruder, a twin-screw extruder, etc. can be used.

[0166] In addition, by molding the resin composition of the present invention by an injection molding method, molded articles of any shape such as packaging containers can be obtained. As the injection molding temperature, the same temperature as the extrusion molding temperature can be adopted. The injection molding machine used in the injection molding method is not particularly limited, and a known injection molding machine can be used.

[0167] In addition, by molding the resin composition of the present invention by a casting molding method, molded articles such as films can be obtained. In the casting molding method, a solution or dispersion liquid in which the resin composition of the present invention is dissolved or dispersed in a solvent is cast, and the solvent is removed, whereby a molded article such as a film can be molded.

[0168] By using the resin composition of the present invention and performing molding by the above-mentioned extrusion molding method, casting molding method, etc., the stretchable film of the present invention can be obtained. As a method for molding the stretchable film of the present invention, from the viewpoint of obtaining a smooth stretchable film with good productivity, the extrusion molding method is preferred, and among them, the extrusion molding method using a T-die is more preferred. As a specific example of the extrusion molding method using a T-die, there can be mentioned a method of extruding the resin composition heated and melted at the above-mentioned molding temperature from the T-die installed in a single-screw extruder, twin-screw extruder or other screw extruders and winding it while cooling with a take-up roll. In addition, when cooling with a take-up roll, the stretchable film can also be stretched. Further, when winding up the stretchable film, it is possible to form a film while coating the melt of the resin composition on a substrate formed of polyethylene terephthalate, polyethylene, polypropylene, non-woven fabric or release paper, or to form a film with the melt of the resin composition sandwiched between these substrates. The stretchable film obtained in this way can be used in a state integrated with the substrate, or can be peeled off from the substrate for use.

[0169] The thickness of the stretchable film is not particularly limited, and is usually 0.01 to 5 mm, preferably 0.03 to 0.5 mm.

[0170] The stretchable film of the present invention can be used as a single layer according to its use, or can be laminated with other members and used as a multi-layer body. As a specific example of using the stretchable film of the present invention as a single layer, there can be mentioned products such as stretchable films (elastic films) used in sanitary products such as disposable diapers and sanitary products; protective films for protecting optical films, etc.; heat-shrinkable films for shrink packaging of containers and heat-shrinkable labels. As a specific example of making the stretchable film of the present invention into a multi-layer body, there can be mentioned the following situation: after slitting the film, applying a hot melt adhesive or other adhesives thereon to make a tape, and adhering the tape to a non-woven fabric, woven fabric, plastic film or their laminate in a shrunk state, and then relaxing the shrinkage of the tape to form a stretchable pleated member. Further, according to other uses, it can be appropriately processed by a known method and can also be used as, for example, a stretchable base material for wet compresses, gloves, surgical gloves, finger cots, tourniquets, contraceptives, headbands, goggle straps, rubber bands and other stretchable members.

[0171] By using the resin composition of the present invention and performing molding by the above-mentioned extrusion molding method, etc., the sheet of the present invention can be obtained. The thickness of the sheet of the present invention is not particularly limited, and is usually 0.5 to 30 mm, preferably 1 to 10 mm. The sheet of the present invention can be used for, for example, the following uses: packaging container materials for packaging clothes, foods, daily groceries, industrial materials, etc.; molding materials such as anti-vibration sheets, shock-absorbing sheets, buffer sheets for electronic and electrical equipment, shock-absorbing sheets for houses, shock-absorbing damping materials, etc.

[0172] By using the resin composition of the present invention and performing molding through the above-mentioned extrusion molding method or the like, the tube of the present invention can be obtained. The tube of the present invention can be used as, for example: tubes for automobiles such as vacuum control tubes, emission control tubes, fuel line tubes, air brake tubes; tubes for hydraulic equipment, pneumatic equipment, centralized lubrication equipment, painting equipment, chemical equipment, solvent / reagent transfer tubes, various liquefied gas transfer tubes, food-related equipment tubes, physical and chemical equipment tubes, metering pump tubes, textile machinery tubes, packaging equipment tubes, printing equipment tubes, conduction equipment tubes, water treatment device tubes, fluid component tubes, industrial robot tubes, industrial vehicle tubes, agricultural machinery tubes, construction machinery tubes, machine tool tubes, injection molding machine tubes, labor-saving machinery tubes, pneumatic tool tubes such as pneumatic devices / hammers, tubes for the operation part, air pressure / electric signal tubes, air pressure / signal tubes, tubes for equipment requiring heat resistance / high insulation / high frequency characteristics, various industrial machinery / industrial vehicle tubes such as spot welding equipment tubes, medical equipment tubes, etc.

[0173] Examples

[0174] Hereinafter, examples and comparative examples are given to further specifically illustrate the present invention, but the present invention is not limited to these examples. In addition, unless otherwise specified, "parts" and "%" are based on weight.

[0175] The test methods carried out in the present examples and comparative examples are as described below.

[0176] [Weight average molecular weight, molecular weight distribution]

[0177] By high performance liquid chromatography with tetrahydrofuran as the carrier at a flow rate of 0.35 ml / minute, a chromatogram of the molecular weight based on polystyrene conversion was obtained and calculated based on the obtained chromatogram. The device is HLC8320 manufactured by Tosoh Corporation, and the chromatographic column is a column formed by connecting 3 Shodex (registered trademark) KF-404HQ columns manufactured by Showa Denko K.K. (column temperature 40 °C). A differential refractometer and an ultraviolet detector are used as detectors, and the molecular weight calibration is carried out with 12 points of standard polystyrene (500,000 - 3,000,000) manufactured by Polymer Laboratories Ltd.

[0178] [Weight ratio of each block copolymer in the (hydrogenated) block copolymer composition]

[0179] It is calculated based on the area ratio of the peaks corresponding to each block copolymer in the chromatogram obtained by the above-mentioned high performance liquid chromatography.

[0180] [Weight average molecular weight of the styrene polymer block of the (hydrogenated) block copolymer]

[0181] The (hydrogenated) block copolymer is reacted with ozone according to the method described in Rubber Chem. Technol., 45, 1295 (1972), and reduced with lithium aluminum hydride, whereby the isoprene polymer block of the (hydrogenated) block copolymer is decomposed.

[0182] Specifically, the following steps are carried out. That is, 300 mg of the sample is dissolved in a reaction vessel containing 100 ml of dichloromethane treated with molecular sieve. The reaction vessel is placed in a cooling bath and set to -25 °C, and then ozone generated by an ozone generator is introduced while oxygen is passed into the reaction vessel at a flow rate of 170 ml / min. After 30 minutes from the start of the reaction, the gas flowing out of the reaction vessel is introduced into an aqueous potassium iodide solution to confirm the completion of the reaction. Next, 50 ml of diethyl ether and 470 mg of lithium aluminum hydride are placed in another reaction vessel purged with nitrogen, and the solution reacted with ozone is slowly added dropwise to this reaction vessel while cooling the reaction vessel with ice water. Then, the reaction vessel is placed in a water bath and slowly heated, and refluxed at 40 °C for 30 minutes. After that, dilute hydrochloric acid is added dropwise in small portions each time to the reaction vessel while stirring the solution, and the addition is continued until the generation of hydrogen can hardly be confirmed. After this reaction, the solid product formed in the solution is filtered out, and the solid product is extracted with 100 ml of diethyl ether for 10 minutes. The extract is combined with the filtrate at the time of filtration, and the solvent is distilled off to obtain a solid sample. For the sample thus obtained, the weight-average molecular weight is measured according to the above-described method for measuring the weight-average molecular weight, and this value is taken as the weight-average molecular weight of the styrene polymer block.

[0183] [Weight-average molecular weight of the (hydrogenated) isoprene polymer block of the (hydrogenated) block copolymer]

[0184] The weight-average molecular weight of the corresponding styrene polymer block is subtracted from the weight-average molecular weight of the (hydrogenated) block copolymer determined as described above, and the weight-average molecular weight of the (hydrogenated) isoprene polymer block is calculated based on this calculated value.

[0185] [Styrene unit content of the (hydrogenated) block copolymer]

[0186] It is calculated based on the ratio of the detection intensities of the differential refractometer and the ultraviolet detector in the above-described high-performance liquid chromatography measurement. In addition, copolymers with different styrene unit contents are prepared in advance, and a standard curve is made using them.

[0187] [Styrene unit content of the whole (hydrogenated) block copolymer composition]

[0188] Based on the measurement of 1 1H-NMR using deuterated chloroform as a solvent.

[0189] [Vinyl bond content of (hydrogenated) isoprene polymer block]

[0190] Determined based on 1 H-NMR measurement using deuterated chloroform as a solvent.

[0191] [Olefin hydrogenation rate (mol%) of (hydrogenated) block copolymer composition]

[0192] By using 1 H-NMR spectroscopic measurement with deuterated chloroform as a solvent, the olefin amounts of the block copolymer composition before hydrogenation and the hydrogenated block copolymer composition after hydrogenation are determined respectively, and the olefin hydrogenation rate (mol%) is calculated based on the difference in olefin amounts before and after hydrogenation.

[0193] In 1 H-NMR spectroscopic measurement, deuterated chloroform is used in the solvent, and JMN-AL series AL400 (manufactured by JEOL Ltd.) is used as the NMR measurement device.

[0194] In addition, in this example and comparative examples, both the block copolymer composition before hydrogenation and the hydrogenated block copolymer composition after hydrogenation contain only isoprene units as the units of monomers derived from olefins. Therefore, the hydrogenation rate of isoprene is determined during measurement and used as the olefin hydrogenation rate.

[0195] [Iodine value of (hydrogenated) block copolymer composition]

[0196] Determined according to JIS K0070.

[0197] [Melt index of (hydrogenated) block copolymer composition]

[0198] Determined according to ASTM D-1238 (condition G, 200 °C, 5 kg).

[0199] [200% modulus]

[0200] By cutting the films obtained in the examples and comparative examples to produce specimens with a width of 25 mm, one of them is measured in the direction perpendicular to the melt flow during molding. The measurement steps are as follows. The specimen is fixed on a Tensilon universal testing machine RTC-1210 manufactured by ORIENTEC Co., Ltd. without tension and with a chuck spacing of 40 mm. Then, the specimen is stretched to 200% at a speed of 300 mm / min, and then restored to the initial chuck spacing at a speed of 300 mm / min. Furthermore, after stretching the specimen to 200% again at the same speed, it is restored to the initial chuck spacing again at the same speed. The tensile stress during the second 200% stretching is taken as the 200% modulus. It can be judged that the higher the 200% modulus, the more excellent the tensile stress.

[0201] [Permanent elongation rate]

[0202] Using the above-mentioned Tensilon universal testing machine, in accordance with ASTM 412, the films obtained in the examples and comparative examples were measured in the direction perpendicular to the melt flow during molding. Specifically, Die A was used for the sample shape, the gauge length before stretching was set to 40 mm, the stretchable film was stretched at a stretching rate of 200%, and after maintaining this state for 10 minutes, it was suddenly shrunk without springback. After leaving it for 10 minutes, the gauge length was measured, and the permanent elongation rate was calculated based on the following formula.

[0203] Permanent elongation rate (%) = (L1 - L0) / L0 × 100

[0204] L0: Gauge length before stretching (mm)

[0205] L1: Gauge length after shrinking and leaving it for 10 minutes (mm)

[0206] It can be judged that the smaller the permanent elongation rate, the more excellent the recovery force.

[0207] [Bag breaking strength]

[0208] The films obtained in the examples and comparative examples were cut out, and two film pieces of 15 cm × 9 cm were made. They were overlapped, and three sides of the four sides were heat-sealed under the conditions of 140 °C, 0.4 MPa, and a heating time of 1 second to make a bag. For the obtained bag, 100 cc of water was injected from the side that was not heat-sealed, and then this side was heat-sealed under the same conditions as above to make a liquid packaging container with a content volume of 100 cc. The obtained liquid packaging container was left standing on an iron plate in an environment of 23 °C, and then an iron plate of 1 kg (9.8 N) was dropped from above the liquid packaging container three times for a drop test. The drop test was first carried out with the vertical distance from the liquid packaging container to the iron plate set to 10 cm. Next, if the liquid packaging container did not break under this condition, the vertical distance from the liquid packaging container to the iron plate was set to 20 cm, and the drop test was carried out again. Similarly, before the liquid packaging container broke, the vertical distance from the liquid packaging container to the iron plate was increased at 10 cm intervals, and the upper limit height (cm) at which no bag breakage occurred was used as an index of the bag breaking strength. There is a tendency that the larger the index of the bag breaking strength, the more excellent the impact resistance. If the index of the bag breaking strength is 40 cm or more, it can be judged that the impact resistance is excellent.

[0209] [Viscosity retention rate]

[0210] The films obtained in the examples and comparative examples were subjected to a thermal degradation test (180 °C × 5 hours; in the presence of air), and the melt viscosity before and after the thermal degradation test was measured. The viscosity retention rate was calculated by the following formula. It can be judged that the higher the viscosity retention rate, the more excellent the thermal stability of the resin composition.

[0211] Viscosity retention rate (%) = (Melt viscosity after thermal degradation test / Melt viscosity before thermal degradation test) × 100

[0212] The melt viscosity was measured using a flow tester CFT-500C (manufactured by Shimadzu Corporation) under the conditions of a temperature of 180 °C, a load of 100 kgf / cm 2 and a die shape of 1 mm Φ × 10 mm.

[0213] [Production Example 1]

[0214] (1) Production of the block copolymer composition before hydrogenation

[0215] 56.6 kg of cyclohexane, 270.6 mmol of ethylene glycol dibutyl ether, and 1.22 kg of styrene were added to a pressure-resistant reactor. While stirring all the contents at 40 °C, 270.6 mmol of n-butyllithium (1.6 M solution) was added. After the addition was completed, the temperature was raised to 50 °C and a polymerization reaction was carried out for 1 hour (first-stage polymerization). The polymerization conversion rate of styrene at this time was 100%.

[0216] Next, while controlling the temperature to maintain 50 - 60 °C, 6.49 kg of isoprene was continuously added to the reactor over 1 hour. After the addition of isoprene was completed, a polymerization reaction was carried out for another 1 hour (second-stage polymerization). The polymerization conversion rate of isoprene at this time was 100%.

[0217] Then, while controlling the temperature to maintain 50 - 60 °C, 1.22 kg of styrene was continuously added over 1 hour. After the addition of styrene was completed, a polymerization reaction was carried out for another 1 hour, thereby obtaining a solution containing a styrene-isoprene-styrene triblock copolymer with active ends (third-stage polymerization). The polymerization conversion rate of styrene at this time was 100%.

[0218] Then, by adding 195 mmol of methanol as a polymerization terminator and mixing, a part of the active ends of the styrene-isoprene-styrene triblock copolymer with active ends was inactivated, and a solution containing a styrene-isoprene-styrene triblock copolymer as block copolymer B', which was used to obtain hydrogenated block copolymer B, was obtained.

[0219] Then, while controlling the temperature to maintain 50 to 60 °C, 1.06 kg of styrene was continuously added over 1 hour. After the addition of styrene was completed, a polymerization reaction was carried out for 1 hour to obtain a solution containing a styrene-isoprene-styrene triblock copolymer with a living end as block copolymer A' (fourth-stage polymerization), and this block copolymer A' was used to obtain a hydrogenated block copolymer A. The polymerization conversion rate of styrene at this time was 100%.

[0220] Finally, 345 mmol of methanol was added as a polymerization terminator and mixed to deactivate all the living ends of the styrene-isoprene-styrene triblock copolymer with a living end, completing the polymerization reaction, and thus a solution containing a block copolymer composition before hydrogenation was obtained.

[0221] The amounts of each reagent used in the reaction are summarized in Table 1.

[0222] (2) Hydrogenation reaction of the block copolymer composition before hydrogenation

[0223] The solution containing the block copolymer composition before hydrogenation obtained above was subjected to a hydrogenation reaction to obtain a solution containing a hydrogenated block copolymer composition. The hydrogenation reaction was carried out as follows: In the solution containing the block copolymer composition before hydrogenation obtained above, Ni(AcAc) 2 -TIBAL catalyst was added as a hydrogenation catalyst, and the reaction was carried out under the conditions of a hydrogen pressure of 3 MPa, a reaction temperature of 80 °C, and a reaction time of 3 hours.

[0224] A part of the solution containing the hydrogenated block copolymer composition obtained in this way was taken out, and the weight-average molecular weight and molecular weight distribution of the hydrogenated block copolymer composition (as a whole), the weight ratio of each hydrogenated block copolymer in the composition, the weight-average molecular weight of the styrene polymer block of each hydrogenated block copolymer, the weight-average molecular weight of the hydrogenated isoprene polymer block of each hydrogenated block copolymer, the styrene unit content of each hydrogenated block copolymer, the styrene unit content of the hydrogenated block copolymer composition (as a whole), the vinyl bond content of the hydrogenated isoprene polymer block of each hydrogenated block copolymer, and the olefin hydrogenation rate of the hydrogenated block copolymer composition (as a whole) were determined. These values are summarized in Table 2.

[0225] (3) Recovery of the hydrogenated block copolymer composition

[0226] To 100 parts of the solution of the hydrogenated block copolymer composition obtained as described above, 0.3 part of 2,6-di-tert-butyl-p-cresol was added as an antioxidant and mixed. The mixed solution was gradually added dropwise in small portions to warm water heated to 85 to 95 °C to volatilize the solvent and obtain a precipitate. The obtained precipitate was pulverized and dried by hot air at 85 °C to recover the hydrogenated block copolymer composition in the form of pellets. The pelletized hydrogenated block copolymer composition was fed to a single-screw extruder having an underwater hot cutting device at the front end of the extruder to produce cylindrical pellets having an average diameter of 5 mm and an average length of about 5 mm. The pellets were put into a hopper dryer heated to 60 °C and dried for 10 hours while passing dry air at 60 °C to obtain the hydrogenated block copolymer composition. The obtained hydrogenated block copolymer composition was measured for iodine value and melt index. The results are summarized in Table 2.

[0227] [Production Example 2]

[0228] The reaction time in the hydrogenation reaction was changed from 3 hours to 1 hour, and otherwise, the same operations as in Production Example 1 were carried out to obtain a hydrogenated block copolymer composition, and the same measurements were carried out. The results are summarized in Table 2.

[0229] [Production Example 3]

[0230] The amounts of styrene, ethylene glycol dibutyl ether, n-butyllithium, isoprene, and methanol were changed as shown in Table 1, respectively, and the reaction time in the hydrogenation reaction was changed from 3 hours to 15 minutes. Otherwise, the same operations as in Production Example 1 were carried out to obtain a hydrogenated block copolymer composition, and the same measurements were carried out. The results are summarized in Table 2.

[0231] [Production Example 4]

[0232] The amounts of styrene, ethylene glycol dibutyl ether, n-butyllithium, isoprene, and methanol were changed as shown in Table 1, respectively, and the reaction time in the hydrogenation reaction was changed from 3 hours to 2 hours. Otherwise, the same operations as in Production Example 1 were carried out to obtain a hydrogenated block copolymer composition, and the same measurements were carried out. The results are summarized in Table 2.

[0233] [Production Example 5]

[0234] (1) Preparation of the block copolymer composition before hydrogenation

[0235] 56.6 kg of cyclohexane, 451.5 mmol of ethylene glycol dibutyl ether, and 1.04 kg of styrene were added to a pressure-resistant reactor. While stirring all the contents at 40 °C, 451.5 mmol of n-butyllithium (1.6 M solution) was added. After the addition was completed, the temperature was raised to 50 °C and a polymerization reaction was carried out for 1 hour (the first-stage polymerization). The polymerization conversion rate of styrene at this time was 100%.

[0236] Next, while controlling the temperature to maintain 50 - 60 °C, 7.99 kg of isoprene was continuously added to the reactor over 1 hour. After the addition of isoprene was completed, a polymerization reaction was carried out for another 1 hour, thereby obtaining a solution containing a styrene-isoprene diblock copolymer having a living end (the second-stage polymerization). The polymerization conversion rate of isoprene at this time was 100%.

[0237] Next, by adding 154 mmol of dimethyldichlorosilane as a difunctional coupling agent and mixing, a part of the styrene-isoprene diblock copolymer having a living end was coupled to obtain a solution containing a styrene-isoprene-styrene triblock copolymer as block copolymer B', which was used to obtain hydrogenated block copolymer B.

[0238] Then, while controlling the temperature to maintain 50 - 60 °C, 0.96 kg of styrene was continuously added over 1 hour. After the addition of styrene was completed, a polymerization reaction was carried out for another 1 hour to obtain a solution containing a styrene-isoprene-styrene triblock copolymer having a living end as block copolymer A', which was used to obtain hydrogenated block copolymer A. The polymerization conversion rate of styrene at this time was 100%.

[0239] Finally, by adding 595 mmol of methanol as a polymerization terminator and mixing, the living ends of the styrene-isoprene-styrene triblock copolymer having a living end were all deactivated, and the polymerization reaction was completed, thereby obtaining a solution containing a pre-hydrogenated block copolymer composition.

[0240] The amounts of each reagent used in the reaction are summarized in Table 1.

[0241] (2) Hydrogenation reaction of the pre-hydrogenated block copolymer composition

[0242] The solution containing the pre-hydrogenated block copolymer composition obtained above was subjected to a hydrogenation reaction to obtain a solution containing a hydrogenated block copolymer composition. The hydrogenation reaction was carried out under the same conditions as in Production Example 1. Then, a part of the obtained solution containing the hydrogenated block copolymer composition was taken out, and various measurements were carried out in the same manner as in Production Example 1. The results are summarized in Table 2.

[0243] (3) Recovery of the hydrogenated block copolymer composition

[0244] Using the obtained solution containing the hydrogenated block copolymer composition, the operation was carried out in the same manner as in Production Example 1 to obtain a hydrogenated block copolymer composition, and then the measurement was carried out in the same manner. The results are summarized in Table 2.

[0245] [Production Example 6]

[0246] (1) Production of the block copolymer composition before hydrogenation

[0247] 56.6 kg of cyclohexane, 284.2 mmol of ethylene glycol dibutyl ether, and 1.75 kg of styrene were added to a pressure-resistant reactor. While stirring all the contents at 40 °C, 284.2 mmol of n-butyllithium (1.6 M solution) was added. After the addition was completed, the temperature was raised to 50 °C and a polymerization reaction was carried out for 1 hour (first-stage polymerization). The polymerization conversion rate of styrene at this time was 100% by weight.

[0248] Next, while controlling the temperature to maintain 50 - 60 °C, 6.49 kg of isoprene was continuously added to the reactor over 1 hour. After the addition of isoprene was completed, a polymerization reaction was carried out for another 1 hour (second-stage polymerization). The polymerization conversion rate of isoprene at this time was 100%.

[0249] Then, while controlling the temperature to maintain 50 - 60 °C, 1.75 kg of styrene was continuously added over 1 hour. After the addition of styrene was completed, a polymerization reaction was carried out for another 1 hour, thereby obtaining a solution containing a styrene-isoprene-styrene triblock copolymer having active ends (third-stage polymerization). The polymerization conversion rate of styrene at this time was 100%.

[0250] Finally, by adding 568.4 mmol of methanol as a polymerization terminator and mixing, all the active ends of the styrene-isoprene-styrene triblock copolymer having active ends were inactivated, and the polymerization reaction was completed, thereby obtaining a solution containing the block copolymer composition before hydrogenation.

[0251] The amounts of the respective reagents used in the reaction are summarized in Table 1.

[0252] (2) Hydrogenation reaction of the block copolymer composition before hydrogenation

[0253] The solution containing the block copolymer composition before hydrogenation obtained above was subjected to a hydrogenation reaction, thereby obtaining a solution containing a hydrogenated block copolymer composition. The hydrogenation reaction was carried out under the same conditions as in Production Example 1. Then, a part of the obtained solution containing the hydrogenated block copolymer composition was taken out, and various measurements were carried out in the same manner as in Production Example 1. The results are summarized in Table 2.

[0254] (3) Recovery of the hydrogenated block copolymer composition

[0255] Using the obtained solution containing the hydrogenated block copolymer composition, the operation was carried out in the same manner as in Production Example 1 to obtain a hydrogenated block copolymer composition, and then the measurement was carried out in the same manner. The results are summarized in Table 2.

[0256] [Production Example 7]

[0257] The amounts of styrene, ethylene glycol dibutyl ether, n-butyllithium, isoprene, and methanol were changed as shown in Table 1, and the hydrogenation reaction was not carried out. Except for this, the operation was carried out in the same manner as in Production Example 1 to produce an unhydrogenated block copolymer composition. Using the obtained unhydrogenated block copolymer composition, the measurement was carried out in the same manner. The results are summarized in Table 2.

[0258] [Production Example 8]

[0259] The amounts of styrene, ethylene glycol dibutyl ether, n-butyllithium, isoprene, and methanol were changed as shown in Table 1, and the hydrogenation reaction was not carried out. Except for this, the operation was carried out in the same manner as in Production Example 6 to produce an unhydrogenated block copolymer composition. Using the obtained unhydrogenated block copolymer composition, the measurement was carried out in the same manner. The results are summarized in Table 2.

[0260] [Table 1]

[0261]

[0262] [Table 2]

[0263]

[0264] [Example 1]

[0265] 30 parts of the hydrogenated block copolymer composition obtained in Production Example 1 and 70 parts of a polypropylene-based resin (trade name “Vistamaxx 6102”, manufactured by ExxonMobil Corporation, an ethylene-propylene copolymer containing propylene units as the main component, ethylene content 16%, MFR 3 g / 10 minutes (230 °C, 2.16 kg ASTM D1238), density 0.862 g / cm 3 ) were put into a twin-screw extruder equipped with a T-die. Then, in this twin-screw extruder, they were heated and melted at 200 °C and kneaded to form a resin composition, which was continuously extruded for 20 minutes in a manner of sandwiching a PET release film to be formed into a film with an average thickness of 0.05 mm, and then the PET release film was removed to obtain a film. In addition, the details of the film forming conditions are as follows.

[0266] (Film forming conditions)

[0267] Complex treatment speed: 5 kg / hour

[0268] Film winding speed: 4 m / minute

[0269] Extruder temperature: adjusted to 100 °C at the inlet and 200 °C at the T-die

[0270] Screw: full thread

[0271] Extruder L / D: 30

[0272] T-die: width 200 mm, die lip 0.5 mm

[0273] Using the obtained film, measure the 200% modulus, permanent elongation, bag-breaking strength, and viscosity retention rate. The results are summarized in Table 3.

[0274] [Examples 2 - 5, Comparative Examples 1 - 3]

[0275] Change the type of the hydrogenated block copolymer composition used as shown in Table 3. Otherwise, prepare the resin composition in the same manner as in Example 1 to obtain a film. Then, use the obtained film and evaluate it in the same manner as in Example 1. The results are summarized in Table 3.

[0276] [Table 3]

[0277]

[0278] As shown in Table 3, for the resin composition containing the hydrogenated block copolymer composition and the polyolefin-based thermoplastic resin C, the hydrogenated block copolymer composition contains the hydrogenated block copolymer A represented by the general formula (A) and the hydrogenated block copolymer B represented by the general formula (B) in a ratio of A / B (weight ratio) = 10 / 90 to 80 / 20, and the hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is 10 - 100%. The obtained film (molded body) balances the tensile stress and the resilience at a high level, has excellent impact resistance, and also has excellent thermal stability (Examples 1 - 5).

[0279] On the other hand, in the case of not containing the hydrogenated block copolymer A represented by the general formula (A), the obtained film (molded body) has poor resilience, cannot balance the tensile stress and the resilience, and furthermore has poor impact resistance (Comparative Example 1).

[0280] In addition, in the case of using a block copolymer composition with an olefin hydrogenation rate of less than 10%, the obtained film (molded body) has poor thermal stability (Comparative Example 2).

[0281] Furthermore, in the case of using a block copolymer composition that does not contain the hydrogenated block copolymer A represented by the general formula (A) and has a hydrogenation rate of olefins of less than 10%, the resulting film (molded article) has poor resilience, cannot balance tensile stress and resilience, and furthermore has poor thermal stability (Comparative Example 3).

Claims

1. A resin composition comprising a hydrogenated block copolymer composition and a polyolefin-based thermoplastic resin C, wherein the hydrogenated block copolymer composition has a hydrogenated block copolymer A represented by the following general formula (A) and a hydrogenated block copolymer B represented by the following general formula (B). The weight ratio (A / B) of the hydrogenated block copolymer A to the hydrogenated block copolymer B in the hydrogenated block copolymer composition is 10 / 90 to 80 / 20. The hydrogenation rate of the olefin in the polymer components constituting the hydrogenated block copolymer composition is 10 to 100%. Ar1 a -HD a -Ar2 a (A) Ar1 b -HD b -Ar2 b (B) In the general formula (A) and the general formula (B), Ar1 a and Ar2 a , Ar1 b and Ar2 b are aromatic vinyl polymer blocks, HD a and HD b are hydrogenated polymer blocks of conjugated diene polymers. The contents of the conjugated diene monomer units containing hydrogenated conjugated diene monomer units in HD a and HD b are each 80% by weight or more. The conjugated diene monomer units are isoprene units. The vinyl bond contents of HD a and HD b are each 10 to 80 mol%. The ratio of the vinyl bond content of HD b to the vinyl bond content of HD a is 0.95 to 1.

05. The weight-average molecular weight (Mw(Ar1 a )) of Ar1 a is 2000 to 5000. The ratio (Mw(Ar2 a )) / Mw(Ar1 a )) of the weight-average molecular weight (Mw(Ar2 a )) of Ar2 a to the weight-average molecular weight (Mw(Ar1 a )) of Ar1 a is 2.6 to 66. The ratio (Mw(Ar2 b )) / Mw(Ar1 b )) of the weight-average molecular weight (Mw(Ar2 b )) of Ar2 b to the weight-average molecular weight (Mw(Ar1 b )) of Ar1 b is 0.95 to 1.

05.

2. The resin composition according to claim 1. Wherein, The proportion of the aromatic vinyl monomer units in all the repeating units of the polymer components of the hydrogenated block copolymer composition is 20 to 70% by weight.

3. The resin composition according to claim 1 or 2. Wherein, The vinyl bond contents of HD in the general formula (A) and general formula (B) of the hydrogenated block copolymer composition a and HD b are each 20 to 80 mol%.

4. The resin composition according to claim 1 or 2. Wherein, In the general formula (A) and the general formula (B) of the hydrogenated block copolymer composition, Ar1 b and Ar2 b have a weight-average molecular weight in the range of 2,000 to 40,000 respectively, and HD a and HD b have a weight-average molecular weight in the range of 10,000 to 300,000 respectively.

5. The resin composition according to claim 1 or 2. Wherein, The ratio (C / A+B) of the content of the polyolefin-based thermoplastic resin C to the total content of the hydrogenated block copolymer A and the hydrogenated block copolymer B is 10 / 90 to 90 / 10 by weight.

6. The resin composition according to claim 1 or 2. Wherein, The weight-average molecular weight of the entire polymer components constituting the hydrogenated block copolymer composition is 30,000 to 400,000.

7. The resin composition according to claim 1 or 2. Wherein, The polyolefin-based thermoplastic resin C is a polypropylene-based resin.

8. A stretchable film made using the resin composition according to any one of claims 1 to 7.

9. A sheet made using the resin composition according to any one of claims 1 to 7.

10. A tube made using the resin composition according to any one of claims 1 to 7.

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