JP2016222885A - Resin composition and molded body containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition capable of providing a compound material excellent in balance among various physical properties such as TPS.SOLUTION: There is provided a resin composition containing 100 pts.mass of (a) a block copolymer containing a polymer block mainly containing a vinyl aromatic compound (A) and a polymer block (B) mainly containing a conjugated diene compound or a hydrogenated article thereof, 1 to 20 pts.mass of a styrene-containing oligomer (b) having a melting viscosity at 160°C of 10 to 150,000 mP s and a percentage content of a structural unit derived from styrene of 10 to 70 mass%, and 0 to 100 pts.mass of a polyolefin resin (c) having an MFR of 0.1 to 500 g/10 min.SELECTED DRAWING: None

Description

  The present invention relates to a specific resin composition and a molded product obtained therefrom.

  Thermoplastic elastomers (TPE) that have the same melt molding processability as general-purpose plastics typified by polyethylene (PE) and polypropylene (PP), as well as flexibility and rubber elasticity similar to crosslinked rubber, are used in automobiles, home appliances and foods. It is applied to a wide range of fields such as medical and daily necessities. There are various types of TPE, such as olefin elastomers, styrene elastomers, polyester elastomers, polyurethane elastomers, polyamide elastomers, and PVC (PVC) elastomers. Among them, styrene elastomers are one of the most used TPEs. One.

  Styrene-based TPE is generally abbreviated as SBC (styrene block copolymer) and is a general term for block copolymers in which a hard segment as a constrained phase is made of polystyrene. The soft segment is a conjugated diene polymer such as butadiene or a hydrogenated product thereof. In SBC, the soft segment and the hard segment have a microphase separation structure at room temperature, so the hard segment becomes a physical cross-linking point, and the performance (flexibility, rubber elasticity) as an elastomer without chemical cross-linking. To express.

  Hydrogenated SBC (HSBC) does not have a double bond in the molecule, and thus exhibits better heat resistance and weather resistance than non-hydrogenated SBC. HSBC is widely used as a compound raw material, and compound materials using such HSBC are generally collectively referred to as TPS.

  In TPS, various materials are blended (polymer alloyed) in order to compensate for the performance that HSBC lacks. Examples of such a material include petroleum resin for improving molding processability.

  Patent Document 1 discloses an example in which vibration control is improved in addition to molding processability using petroleum resin. However, in order to optimize molding processability in TPS, the amount of petroleum resin is limited. When a large amount of petroleum resin is blended in order to further improve the moldability, rigidity is lowered instead of improving flexibility and fluidity (improving moldability). There were problems such as a significant decrease in mechanical properties.

JP 2004-196896 A

  This invention makes it a subject to provide the resin composition which can give the compound material excellent in the balance of various physical properties in compound materials, such as TPS mentioned above. Further, according to the study by the present inventors, it is considered necessary to improve the sag resistance in order to improve the sealing performance in a molded body such as a sealing material and a packing material, and the present invention is a compound such as TPS. Improvement of compression set in materials is a further issue.

The present invention relates to the following [1] to [15].
[1] A block copolymer containing a polymer block (A) mainly composed of a vinyl aromatic compound and a polymer block (B) mainly composed of a conjugated diene compound, or a hydrogenated product thereof (a) 100 parts by mass 1 to 20 parts by mass of a styrene-containing oligomer (b) having the following characteristics (A1) and (A2), and a melt flow rate under a load of 2.16 kg at 230 ° C. measured in accordance with ASTM D1238 Resin composition containing polyolefin resin (c) 0-100 parts by mass with (MFR) 0.1-500 g / 10 min:
(A1) The melt viscosity at 160 ° C. is 10 to 150,000 mP · s;
(A2) The content rate of the structural unit derived from styrene is 10-70 mass%.
[2] The resin composition according to [1], wherein the styrene-containing oligomer (b) is included in an amount of 6 to 16 parts by mass with respect to 100 parts by mass of the block copolymer or a hydrogenated product (a) thereof.
[3] In the block copolymer or the hydrogenated product (a) thereof, the block copolymer contains the polymer block (A) in a range of 20 to 40% by mass. 2].
[4] When the total of the block copolymer or its hydrogenated product (a) and the styrene-containing oligomer (b) is 100 parts by mass, the polymer block (A) and the (b) The resin composition according to any one of [1] to [3], wherein the total mass is in the range of 34 to 66 parts by mass.
[5] When the total of the block copolymer or its hydrogenated product (a) and the styrene-containing oligomer (b) is 100 parts by mass, the polymer block (A) and the (b) The resin composition according to any one of [1] to [3], wherein the total mass is in the range of 34 to 50 parts by mass.
[6] The resin composition according to any one of [1] to [5], wherein the styrene-containing oligomer (b) further has one or more of the following characteristics (A3) to (A6). :
(A3) 50-70 parts by mass of a structural unit derived from α-methylstyrene and 30-50 parts by mass of a structural unit derived from styrene (however, a structural unit derived from α-methylstyrene and a structural unit derived from styrene) The total is 100 parts by mass);
(A4) the softening point is in the range of 80-150 ° C;
(A5) The glass transition temperature (Tg) measured with a differential scanning calorimeter (DSC) is in the range of 0 to 100 ° C .;
(A6) iodine value is in the range of 100g_I ₂ / 100g.
[7] The above-mentioned [1], wherein the styrene-containing oligomer (b) is a styrene-modified product of a copolymer of ethylene and at least one α-olefin selected from α-olefins having 3 to 12 carbon atoms. ] The resin composition in any one of [6].
[8] The resin composition according to any one of [1] to [7], further having the following feature (B1):
(B1) One-dimensional scattering curve for small-angle X-ray scattering (the horizontal axis is the size of the scattering vector q (where q = (4π / λ) sin (θ / 2), where X-ray wavelength is λ, θ is the scattering angle) And the vertical axis represents the logarithm of the scattering intensity I (q), and when the q value of the primary peak is q1 and the q value of the secondary peak is q2, the block copolymer or its The ratio (q2 / q1) of q1 and q2 of the hydrogenated product (a) is in the range of 1.6 to 1.8, and the ratio of q1 and q2 (q2 / q1) in the resin composition is 1. It is in the range of 9 to 2.1.
[9] The resin composition according to any one of [1] to [8], wherein the polyolefin resin (c) is a polypropylene resin.
[10] The system according to any one of [1] to [9], further containing 5 to 300 parts by mass of oil with respect to 100 parts by mass in total of the components (a), (b) and (c). Resin composition.
[11] The system according to any one of [1] to [10], further containing 5 to 20 parts by mass of filler with respect to 100 parts by mass in total of the components (a), (b) and (c). Resin composition.
[12] A molded article comprising the resin composition according to any one of [1] to [11].
[13] A sealing material comprising the resin composition according to any one of [1] to [11].
[14] A packing material comprising the resin composition according to any one of [1] to [11].
[15] A cap liner comprising the resin composition according to any one of [1] to [11].

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which can give the compound material excellent in the balance of various physical properties in compound materials, such as TPS, can be provided. Moreover, molded objects, such as a sealing material and packing material, obtained from the said resin composition can be provided.

The one-dimensional scattering curves of small angle X-ray scattering (SAXS) in Examples 1 to 5, Comparative Example 1 and Comparative Example 2 are shown.

  Hereinafter, the present invention will be specifically described. In the following description, “n1 to n2” (n1 and n2 are numerical values) indicating a numerical range represents a range of n1 or more and n2 or less unless otherwise specified.

<Resin composition>
The resin composition of the present invention comprises a block copolymer containing a polymer block (A) mainly composed of a vinyl aromatic compound and a polymer block (B) mainly composed of a conjugated diene compound, or a hydrogenated product thereof ( a) 1 to 20 parts by mass of a styrene-containing oligomer (b) having the characteristics of (A1) and (A2) described later with respect to 100 parts by mass, and 230 ° C. and a 2.16 kg load measured in accordance with ASTM D1238 The polyolefin resin (c) whose lower MFR is 0.1 to 500 g / 10 min is included in an amount of 0 to 100 parts by mass. Hereinafter, (a), (b) and (c) are also referred to as “component (a)”, “component (b)” and “component (c)”, respectively.

(A) Block copolymer or hydrogenated product thereof (a) In the block copolymer or hydrogenated product thereof, the block copolymer comprises a polymer block (A) mainly composed of a vinyl aromatic compound and And a polymer block (B) mainly composed of a conjugated diene compound, and hereinafter also referred to as “(A) / (B) block copolymer”.

  Specific examples of the vinyl aromatic compound constituting the polymer block (A) include styrene, α-methylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene. 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4- (phenylbutyl) styrene, monochlorostyrene, dichlorostyrene, methoxystyrene, indene, acenaphthylene and the like, and 1 of these vinyl aromatic compounds Species or two or more can be used. Of these, styrene is most preferred. In the present invention, the vinyl aromatic compound includes vinylidene aromatic compounds and vinylene aromatic compounds (including cyclic compounds).

  The conjugated diene compound constituting the polymer block (B) is preferably a conjugated diene having 4 to 20 carbon atoms, and specific examples include butadiene, isoprene, hexadiene and the like. Species or two or more can be used. Of these, butadiene and isoprene are most preferred.

  The (A) / (B) block copolymer preferably has a polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of 30,000 to 500,000. More preferably, it is 000-300,000. When the mass average molecular weight of the (A) / (B) block copolymer is 30,000 or more, the mechanical properties of the molded product obtained from the resin composition are improved, and on the other hand, the resin composition is 500,000 or less. The moldability and workability of the are good.

GPC measurement can be performed, for example, by the method described in the examples.
The polymer block (A) is a block mainly composed of a vinyl aromatic compound, that is, a block mainly composed of a structural unit derived from a vinyl aromatic compound. Here, the “main body” means that the proportion of the structural unit derived from the vinyl aromatic compound is usually 90% by mass or more, preferably 95% by mass or more in 100% by mass of the polymer block (A). .

  The polymer block (B) is a block mainly composed of a conjugated diene compound, that is, a block mainly composed of a structural unit derived from a conjugated diene compound. Here, “main body” means that the proportion of the structural unit derived from the conjugated diene compound in the polymer block (B) is usually 90% by mass or more, preferably 95% by mass or more.

  The ratio of the polymer block (A) to the polymer block (B) in the (A) / (B) block copolymer is the number average molecular weight of the (A) / (B) block copolymer, the polymer block ( It depends on the number average molecular weight of A) and the polymer block (B). Generally, based on the mass of the (A) / (B) block copolymer, the proportion of the polymer block (A) is 5 to 80 mass% and the proportion of the polymer block (B) is 95 to 20 mass%. Is preferable, the ratio of the polymer block (A) is 10 to 75% by mass, the ratio of the polymer block (B) is more preferably 90 to 25% by mass, and the ratio of the polymer block (A) is 20 to 20%. It is more preferable that the proportion of the polymer block (B) is 60 to 80% by mass at 40% by mass. Particularly preferably, the ratio of the polymer block (A) is 20 to 34% by mass, the ratio of the polymer block (B) is 66 to 80% by mass, and the ratio of the polymer block (A) is particularly preferably 20 to 33% by mass. The ratio of the polymer block (B) is 67 to 80% by mass.

  In the (A) / (B) block copolymer, the proportion of the polymer block (A) is 5% by mass or more (that is, the proportion of the polymer block (B) is 95% by mass or less). (A) / (B) Mechanical properties such as a resin composition containing a block copolymer and a molded article obtained therefrom are good, while the proportion of the polymer block (A) is 80% by mass or less. (That is, when the proportion of the polymer block (B) is 20% by mass or more), the melt viscosity does not become too high, and the moldability and workability are good.

The above ratio can be measured, for example, by ¹ H-NMR. When using commercially available products, catalog values may be used.
The (A) / (B) block copolymer may be either linear or branched in two or more, and at least one polymer block (A) in the molecule. The structure is not particularly limited as long as it has at least one polymer block (B). From the balance of mechanical properties, heat resistance, and workability, an ABA type triblock structure is particularly preferable.

  Specific examples include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, and styrene-butadiene / isoprene-styrene block copolymers. For example, a styrene-butadiene-styrene block copolymer means a block copolymer in the form of polystyrene block-polybutadiene block-polystyrene block.

  The method for producing the (A) / (B) block copolymer is not particularly limited. For example, using a suitable polymerization initiator system, a vinyl aromatic compound such as styrene and a conjugated diene such as butadiene in an inert solvent. It can be produced by sequentially polymerizing the compound.

  Examples of the polymerization initiator system in that case include a mixed system of a Lewis acid and an organic compound having a functional group that generates a cationic polymerization active species by the Lewis acid. Examples of the Lewis acid include titanium tetrachloride, tin tetrachloride, boron trichloride, and aluminum chloride. Examples of the organic compound include organic compounds having a functional group such as an alkoxy group, an acyloxy group, or a halogen such as bis (2- Methoxy-2-propyl) benzene, bis (2-acetoxy-2-propyl) benzene, bis (2-chloro-2-propyl) benzene and the like.

  Furthermore, together with the above Lewis acid and organic compound, amides such as N, N-dimethylacetamide and esters such as ethyl acetate may be used as the third component as necessary. Further, as an inert solvent for polymerization, hexane, cyclohexane, methylcyclohexane, methyl chloride, methylene chloride and the like can be used.

  The linear (A) / (B) block copolymer uses, for example, (1) an organic compound having one functional group that generates a cationic polymerization active species by Lewis acid and Lewis acid as a polymerization initiator system. First, a vinyl aromatic compound is polymerized to form a polymer block (A), and then a conjugated diene compound is added to the reaction system and polymerized to form a polymer block (B). Further, a method of forming a polymer block (A) by adding a vinyl aromatic compound to the reaction system and polymerizing it, (2) Lewis acid as a polymerization initiator system and a functional group that generates a cationic polymerization active species by Lewis acid First, a conjugated diene compound is polymerized using an organic compound having two to form a polymer block (B), and then a vinyl aromatic compound is added to the reaction system to polymerize the polymer block (A). It can be produced by a method of forming.

  The branched (A) / (B) block copolymer uses, for example, Lewis acid and an organic compound having three or more functional groups that generate a cationic polymerization active species by Lewis acid as a polymerization initiator system. First, the conjugated diene compound is polymerized to form the polymer block (B), and then the vinyl aromatic compound is added to the reaction system and polymerized to form the polymer block (A). be able to.

  In the resin composition of the present invention, as the component (a), a hydrogenated product of the above (A) / (B) block copolymer can also be used. When a hydrogenated product is used, it is preferable in that heat resistance and weather resistance are improved by reducing the number of aliphatic double bonds in the (A) / (B) block copolymer by hydrogenation.

  In the present invention, the hydrogenated product of the (A) / (B) block copolymer used as the component (a) includes 90% to 100% aliphatic dihydric acid of the (A) / (B) block copolymer. Preferred are hydrogenated heavy bonds and hydrogenated 0% to 10% aromatic double bonds, 99 to 100% aliphatic double bonds hydrogenated and 0% to 5% A hydrogenated aromatic double bond is particularly preferred. In such a hydrogenated product of the (A) / (B) block copolymer, the polymer block (B) in which the aliphatic double bond is hydrogenated substantially becomes a block having a polyolefin structure.

  A publicly known method can be adopted for hydrogenation of the (A) / (B) block copolymer. Examples of the hydrogenation catalyst include catalysts such as nickel, porous diatomaceous earth, Raney nickel, copper dichromate and molybdenum sulfide, and catalysts having platinum, palladium and the like supported on a carrier such as carbon.

  Hydrogenation is performed at any pressure (eg, atmospheric pressure to 300 atmospheres, preferably 5 atmospheres to 200 atmospheres), any temperature (eg, 20 ° C. to 350 ° C.), and any time (eg, 0.2 hours to 10 hours). be able to.

  The component (a) is a combination of two or more types of (A) / (B) block copolymers or hydrogenated products thereof having different properties such as mass average molecular weight and content rate of structural units derived from vinyl aromatic compounds. Also good.

  Component (a) is commercially available, and these commercially available products can be used. Non-hydrogenated products include, for example, “D Series” manufactured by Kraton Polymer Co., Ltd., “TR Series” manufactured by JSR Corporation, “Tuffprene (trademark)” and “Asaprene (trademark)” manufactured by Asahi Kasei Chemicals Corporation. Examples of hydrogenated products include “Septon (trademark)” and “Hibler (trademark)” manufactured by Kuraray Co., Ltd., “Toughtech (trademark)” manufactured by Asahi Kasei Chemicals Corporation, “Dynalon (trademark)” manufactured by JSR Corporation, “ G series ".

(B) Styrene-containing oligomer The styrene-containing oligomer which is the component (b) has the following features (A1) and (A2), preferably one of the following features (A3) to (A6): It further has the above.

  (A1) The melt viscosity at 160 ° C. is 10 to 150,000 mP · s. Preferably it is 20-145,000 mP * s, More preferably, it is 30-140,000 mP * s. The melt viscosity is preferably not less than the lower limit in terms of kneadability when compounding the resin composition, and is preferably not more than the upper limit in terms of improving the fluidity of the resin composition.

  (A2) The content rate of the structural unit derived from styrene (hereinafter also referred to as “styrene structural unit”) is 10 to 70% by mass. Components other than styrene structural units include structural units derived from vinyl aromatic compounds other than styrene, structural units derived from unsaturated aliphatic compounds, and polymer parts derived from olefinic waxes such as ethylene / α-olefin copolymers. Can be mentioned. The content of the styrene structural unit is preferably 15 to 65% by mass, more preferably 20 to 60% by mass. When the content of the styrene structural unit is equal to or higher than the lower limit, it is preferable in terms of heat stability of the styrene-containing oligomer (b). And the softening point can be suppressed from being excessively high. The method for calculating the content of styrene structural units is as described in the Examples section.

  (A3) A structural unit derived from α-methylstyrene is included. Preferably, 50 to 70 parts by mass of a structural unit derived from α-methylstyrene and 30 to 50 parts by mass of a structural unit derived from styrene (however, a structural unit derived from α-methylstyrene and a structural unit derived from styrene are included. The total is 100 parts by mass). The content of the structural unit derived from α-methylstyrene is more preferably 53 to 67 parts by mass, particularly preferably 55 to 65 parts by mass, and the content of the structural unit derived from styrene is more preferably 33 to 47 parts by mass, Especially preferably, it is 35-45 mass parts. When the content of the structural unit derived from α-methylstyrene is not less than the lower limit, it is possible to prevent the molecular weight of the styrene-containing oligomer (b) from being excessively increased and the softening point from being excessively increased. When the content of the structural unit derived from methylstyrene is not more than the above upper limit value, it is preferable from the viewpoint of heat resistance stability of the styrene-containing oligomer (b).

The total content of the structural unit derived from α-methylstyrene and the structural unit derived from styrene in the component (b) is preferably 90% by mass or more, and more preferably 100% by mass.
(A4) The softening point is in the range of 80 to 150 ° C. Preferably it is 100-148 degreeC, More preferably, it exists in the range of 120-145 degreeC. When the softening point is equal to or higher than the lower limit value, it is preferable in terms of improving mechanical properties (reinforcing effect of the styrene phase) by reinforcing the styrene domain phase (physical crosslinking point) of the resin composition, and when the softening point is equal to or lower than the upper limit value. This is preferable from the viewpoint of processability when the composition is compounded.

  (A5) The glass transition temperature (Tg) measured with a differential scanning calorimeter (DSC) is in the range of 0 to 100 ° C. The DSC measurement method will be described in detail in the Examples section. Tg is preferably in the range of 10 to 95 ° C, more preferably 20 to 90 ° C. Tg is preferably at least the lower limit in terms of improving the heat resistance of the resin composition, and Tg is preferably not more than the upper limit in terms of workability when compounding the resin composition.

(A6) iodine value is in the range of 100g_I ₂ / 100g. Preferably 90g_I ₂ / 100g or less, more preferably in the range of 80g_I ₂ / 100g. When the iodine value is in the above range, it is preferable from the viewpoint of heat resistance stability of the styrene-containing oligomer (b).

[Method for producing styrene-containing oligomer (b)]
Examples of the method for producing the styrene-containing oligomer (b) in the present invention include the following methods (1) and (2).

(1) A method of obtaining component (b) by copolymerizing styrene as a raw material with other monomers (eg, vinyl aromatic compounds other than styrene, unsaturated aliphatic compounds).
(2) A method of obtaining component (b) by graft-modifying olefin wax with styrene.

Below, each manufacturing method of (1) and (2) is demonstrated.
Examples of the vinyl aromatic compound other than styrene used as appropriate in the method of (1) above include α-methylstyrene, substituted styrene having a substituent on the aromatic ring, and substituted α-having a substituent on the aromatic ring. Examples thereof include styrene monomers such as methylstyrene. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a halogen atom. Examples of the substituted styrene include methyl styrene, ethyl styrene, 2,4-dimethyl styrene, pn-butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, p- Examples thereof include n-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-phenyl styrene, p-chloro styrene, and 3,4-dichloro styrene. Of these, α-methylstyrene and methylstyrene are preferable.

  In the method (1), examples of the unsaturated aliphatic compound used as appropriate include unsaturated aliphatic hydrocarbons having 4 to 5 carbon atoms and the like. As the unsaturated aliphatic hydrocarbon having 4 to 5 carbon atoms, any fraction selected from fractions containing as a main component an unsaturated aliphatic hydrocarbon having 4 to 5 carbon atoms which is by-produced during petroleum refining and decomposition is used. it can. By using these components in combination, each physical property such as the softening point can be adjusted according to the use.

  A fraction containing an unsaturated aliphatic hydrocarbon having 4 to 5 carbon atoms produced as a by-product during petroleum refining and cracking (hereinafter also referred to as a C4 or C5 fraction) has a boiling range of usually −15 to + 45 ° C. under normal pressure. 1-butene, isobutene, 2-butene, 1,3-butadiene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-pentene, isoprene, 1, It contains polymerizable monomers such as 3-pentadiene and cyclopentadiene. Any fraction containing a polymerizable monomer selected from these C4 and C5 fractions can be used without limitation. Preferably, a fraction having a conjugated double bond such as 1,3-butadiene, isoprene, 1,3-pentadiene or cyclopentadiene is excluded or a fraction having a low content is used.

  The oil fraction as described above is produced as a by-product in, for example, a light oil fraction containing a gas fraction by-produced during atmospheric distillation (topping) of crude oil or the like in a refinery or the like, a cracking of oil, and a reforming process. A similar light oil fraction, or a light oil fraction such as a light oil fraction containing gas obtained in petroleum naphtha cracking at a petrochemical plant, or a distillation, extraction, or other treatment may be added to obtain a desired distillate. Can be obtained as a minute.

  The polymerization reaction of styrene or the copolymerization reaction of styrene with other monomers is mainly performed in the presence of cationic polymerization, more specifically in the presence of a Friedel-Crafts catalyst. As the Friedel-Crafts catalyst, known Friedel-Crafts catalysts can be used, and specifically, aluminum chloride, aluminum bromide, dichloromonoethylaluminum, titanium tetrachloride, tin tetrachloride, boron trifluoride, trifluoride. Examples thereof include various complexes such as an ether complex and a phenol complex of boron bromide. Among these, it is preferable to use a phenol complex of boron trifluoride. The amount of the Friedel-Crafts catalyst used is usually in the range of 0.05 to 5 parts by mass, preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the total raw material.

  The polymerization reaction is carried out using a solvent so that the concentration of the polymerizable monomer as a raw material is about 10 to 60% by mass in order to remove the reaction heat of the polymerization reaction, suppress the viscosity of the reaction solution, and adjust the molecular weight. It is preferable. Examples of suitable solvents include aliphatic hydrocarbons such as pentane, hexane, heptane, and octane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, and methylcyclohexane; aromatic hydrocarbons such as toluene, xylene, ethylbenzene, and mesitylene. Can be mentioned. Of course, these may be used in combination.

  In the polymerization step, a polymerizable monomer that is a raw material in the reactor is subjected to a polymerization reaction in the solvent in the presence of the catalyst. The polymerization step can be carried out in a single stage, but is preferably carried out in a plurality of stages. The polymerization temperature varies depending on the raw material composition, the target molecular weight region, and the like, but is usually preferably in the range of −50 to + 50 ° C. The reaction time is preferably in the range of usually 10 minutes to 10 hours. After completion of the polymerization, the catalyst is decomposed using a basic compound such as a basic aqueous solution or an alcohol such as methanol, then washed with water, and removed by stripping unreacted raw materials and solvents. The component (b) can be obtained.

In the method (2), the component (b) is obtained by reacting the olefin wax with styrene.
Examples of the olefin wax include polyethylene wax and polypropylene wax, and may be a wax obtained by polymerizing olefin, or may be a wax obtained by thermally decomposing high molecular weight polyethylene or polypropylene. Good.

  Production of waxes obtained by polymerizing olefins can be performed by any conventionally known method. For example, olefins can be polymerized using a titanium-based catalyst, a vanadium-based catalyst, a metallocene catalyst, or the like.

  The olefin wax is particularly preferably an ethylene homopolymer or a copolymer of ethylene and an α-olefin having 3 to 12 carbon atoms. The α-olefin may be linear or branched, and may be substituted or unsubstituted.

  As the α-olefin, an α-olefin having 3 to 10 carbon atoms is more preferable, propylene having 3 carbon atoms, 1-butene having 4 carbon atoms, 1-pentene having 5 carbon atoms, carbon Examples thereof include 1-hexene having 6 atoms, 4-methyl-1-pentene, and 1-octene having 8 carbon atoms, and propylene, 1-butene, 1-hexene and 4-methyl-1-pentene are particularly preferable. Can be mentioned.

  The form of the olefinic wax as described above may be any form of a resin and an elastomer, and the steric structure can be used with either an isotactic structure or a syndiotactic structure. There is no limit. Commercially available olefin waxes can be used as they are.

  In addition to styrene to be reacted with the olefinic wax, for example, the vinyl aromatic compound described in the production method (1) may be used in combination, but styrene is preferably used alone.

  The method of graft modification is not particularly limited, and can be performed according to various conventionally known methods. For example, an olefinic wax, styrene and an organic peroxide are simultaneously or sequentially charged into, for example, a Henschel mixer, a V-type blender, a tumbler blender, a ribbon blender, etc. It can be obtained by melt-kneading with a screw extruder, kneader, Banbury mixer or the like. When an apparatus excellent in batch-type melt kneading performance such as an autoclave is used, a styrene-containing oligomer (b) in which each component is dispersed and reacted more uniformly can be obtained. Compared to the continuous type, the batch type is easy to adjust the residence time and can take a longer residence time, so it is relatively easy to increase the modification rate and modification efficiency of styrene.

  Examples of the organic peroxide include di-t-butyl peroxide. Moreover, various additives can be mix | blended as needed. For example, a softener, a stabilizer, a filler, an antioxidant and the like can be blended.

(C) Polyolefin-based resin The resin composition of the present invention is a polyolefin having a melt flow rate (MFR) of 0.1 to 500 g / 10 min under a load of 2.16 kg measured at 230 ° C. according to ASTM D1238, if desired. System resin (c) may be included.

The component (c) polyolefin resin is a polymer or copolymer of at least one olefin monomer.
The component (c) is not particularly limited as long as it is a polymer mainly composed of olefin and MFR satisfies 0.1 to 500 g / 10 minutes, and various known olefin polymers are used. obtain. For example, ethylene, propylene, butene-1, pentene-1, 4-methyl-1-pentene, hexene-1, heptene-1, octene-1, decene-1, undecene-1, dodecene-1, tridecene-1, Examples thereof include homopolymers or copolymers of α-olefins having 2 to 20 carbon atoms such as tetradecene-1, pentadecene-1, hexadecene-1, heptadecene-1, octadecene-1, nonadecene-1, and eicosene-1. . Specifically, high-pressure method low-density polyethylene, linear low-density polyethylene (so-called LLDPE), medium-density polyethylene, high-density polyethylene, polypropylene, polypropylene random copolymer, poly-1-butene, poly-4-methyl-1-pentene , A composition containing olefin polymers such as low crystalline or amorphous ethylene / propylene random copolymer, ethylene / butene-1 random copolymer, propylene / butene-1 random copolymer alone or in combination of two or more thereof , Ethylene / vinyl acetate copolymer (EVA), ethylene / (meth) acrylic acid copolymer or metal salt thereof, and ethylene-cyclic olefin copolymer.

  The component (c) may contain a non-conjugated diene as an olefin copolymerization component. Specific examples of non-conjugated dienes include 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6. -Chain non-conjugated dienes such as octadiene, cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene Cyclic non-conjugated dienes such as 6-chloromethyl-5-isopropylenyl-2-norbornene, 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl- Examples include triene such as 2,2-norbornadiene, 1,3,7-octatriene, 1,4,9-decatriene. Of these, 1,4-hexadiene and cyclic non-conjugated dienes, particularly dicyclopentadiene and 5-ethylidene-2-norbornene are preferably used. Further, these polyolefin resins may be polymers obtained by graft modification with polar compounds such as maleic acid and silane compounds.

Among these, the component (c) is preferably a homopolymer or copolymer of an α-olefin having 2 to 20 carbon atoms, preferably 2 to 10 carbon atoms.
Component (c) is not particularly limited in intrinsic viscosity [η] measured in decalin at 135 ° C., but is preferably 0.5 dl / g or more and 5 dl / g or less. When the intrinsic viscosity [η] measured in 135 ° C. decalin is equal to or higher than the lower limit, the resin composition has good mechanical strength, and when it is equal to or lower than the upper limit, the resin composition has good moldability.

  Suitable examples of the component (c) include polyethylene, polypropylene, polybutene, and the like. In particular, a polypropylene resin that is a homopolymer of propylene or a copolymer mainly composed of propylene is a heat resistant resin composition. It is preferable in terms of improvement in properties, mechanical strength, and solidification speed.

Examples of the polypropylene resin include a propylene homopolymer, and a copolymer of propylene and at least one monomer selected from ethylene and an α-olefin having 4 to 20 carbon atoms. When the polypropylene resin is a copolymer, the proportion of the structural unit derived from propylene is preferably 90 mol% or more, and more preferably 93 to 99 mol%.
Component (c) may be a combination of two or more polyolefin resins having different properties such as the type and MFR.

Resin Composition The resin composition of the present invention is a composition containing the component (a) and the component (b) described above as essential components, and the component (c) as necessary. .

  The resin composition of this invention contains (b) component in the ratio of 1-20 mass parts with respect to 100 mass parts of (a) component. The lower limit of the proportion of component (b) is preferably 5 parts by mass, more preferably 6 parts by mass, even more preferably 8 parts by mass, and the upper limit is preferably 16 parts by mass, more preferably 15 parts by mass, and even more preferably 12 parts by mass. Part.

  Moreover, the resin composition of this invention is a ratio of 0-100 mass parts of (c) component with respect to 100 mass parts of (a) component, Preferably it is 1-80 mass parts, More preferably, it is a ratio of 10-60 mass parts. Contains. In addition, that a resin composition contains (c) component in the ratio of 0 mass part means that the resin composition does not contain (c) component. That is, the resin composition of the present invention does not contain the component (c) or contains the component (c) at a ratio of 100 parts by mass or less with respect to 100 parts by mass of the component (a).

  When the content of the component (b) with respect to 100 parts by mass of the component (a) is 1 part by mass or more, the effect of improving the mechanical properties and moldability by the component (b) is sufficiently exhibited. It is preferable for the amount to be equal to or less than part by mass because bleeding out of the resin composition hardly occurs. When the content of the component (b) is in the above preferred range, it is also preferable in improving compression set. Moreover, when a resin composition contains (c) component, the heat resistance of a resin composition, mechanical strength, and a solidification rate improve, and it is preferable.

  Moreover, in the resin composition of this invention, when the sum total of (a) component and (b) component is 100 mass parts, the sum total of the polymer block (A) and (b) component in (a) component The mass is preferably in the range of 34 to 66 parts by mass. The lower limit of the range is more preferably 35 parts by mass, and still more preferably 36 parts by mass. It is preferable in the range to improve the compression set. It is because it is estimated that it exists in the said range that a resin composition is easy to satisfy | fill the characteristic (B1) mentioned later. The upper limit of the range is more preferably 50 parts by mass. This is because the upper limit of the content of the component (b) in the resin composition is 20 parts by mass with respect to 100 parts by mass of the component (a), and the content of the polymer block (A) in the component (a) Furthermore, it is calculated | required from a preferable upper limit being 40 mass%.

[Other ingredients]
The resin composition of this invention may contain components other than said (a), (b), (c) in the range which does not impair the objective of this invention. The components that may be contained in the resin composition of the present invention include resin components other than the above (a), (b), and (c), oil, various weathering stabilizers, heat stabilizers, antioxidants, ultraviolet absorption Agent, antistatic agent, anti-slip agent, anti-blocking agent, anti-fogging agent, nucleating agent, lubricant, pigment, dye, anti-aging agent, hydrochloric acid absorbent, inorganic or organic filler, organic or inorganic foaming agent, Examples thereof include a crosslinking agent, a co-crosslinking agent, a crosslinking aid, an adhesive, a softener, and a flame retardant.

  Examples of the oil include conventionally known oils such as mineral oil obtained by refining petroleum and synthetic hydrocarbon oil obtained by polymerizing monomers such as ethylene and α-olefin. These can be used alone or in combination of two or more.

  Mineral oil generally has several grades depending on the method of refining, but any of API classification groups (I) to (III) may be used. In general, mineral oils containing 0.5 to 10% by weight of wax are used. For example, a highly refined oil having a composition mainly composed of isoparaffin having a low pour point and a high viscosity index produced by a hydrogenolysis refining method can be used. Among them, the group of mineral oil products generally sold as process oils has a particularly low volatile content and is suitable as a softening agent for the block copolymer or its hydrogenated product as component (a). Specific examples of the process oil include paraffinic process oil, aromatic process oil, and naphthenic process oil. Among them, paraffinic process oils with a low content of unsaturated components such as aromatic components are excellent in heat resistance and weather resistance and are preferably used. In addition, synthetic oil (GTL) obtained by polymerizing natural gas by a Fischer-Trops reaction and performing hydrogenolysis purification can also be used.

Among these, process oil is preferable from the viewpoint of availability and low volatility, and paraffinic process oil is particularly preferable from the viewpoint of heat resistance and weather resistance.
Synthetic hydrocarbon oils include, for example, ethylene / α-olefin copolymers, α-olefin copolymers (PAO), alkylbenzenes, alkylnaphthalenes, etc., and these may be used alone or in combination of two or more. Can be used. Among these, synthetic hydrocarbon oils composed of an ethylene / α-olefin copolymer have good compatibility with the component (a) and are particularly suitable as oils.

  The ethylene / α-olefin copolymer used as a synthetic hydrocarbon oil is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms. As the α-olefin, propylene, 1-butene, 1- Pentene, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene linear α-olefin, 3-methyl-1-pentene, 4-methyl-1-pentene, 8-methyl-1-nonene, 7-methyl-1-decene, 6 Examples include α-olefins having a branch such as -methyl-1-undecene and 6,8-dimethyl-1-decene, preferably linear α-olefins. A fin, one or two or more kinds of these may be used if necessary. Among these α-olefins, α-olefins having 3 to 10 carbon atoms are preferable, and propylene is particularly preferable in terms of imparting good flexibility, vibration damping properties, and weather resistance to the resin composition.

  The content of oil in the resin composition of the present invention is preferably 500 parts by mass or less, more preferably 5 to 300 parts by mass with respect to 100 parts by mass in total of the components (a), (b) and (c). Part.

  As a filler (filler), an inorganic filler is preferable, and powder fillers such as mica, carbon black, silica, calcium carbonate, talc, graphite, stainless steel, and aluminum; fibrous fillers such as glass fiber and metal fiber, etc. Can be mentioned. Among these, mica is preferable because it has an effect of improving the attenuation.

  The content of the filler in the resin composition of the present invention is preferably 50 parts by mass or less, more preferably 5 to 20 with respect to 100 parts by mass in total of the components (a), (b) and (c). Part by mass.

[Other features]
The resin composition of the present invention preferably further has the following feature (B1).
(B1) One-dimensional scattering curve for small-angle X-ray scattering (the horizontal axis is the size of the scattering vector q (where q = (4π / λ) sin (θ / 2), where X-ray wavelength is λ, θ is the scattering angle) And the vertical axis represents the logarithm of the scattering intensity I (q), and when the q value of the primary peak is q1 and the q value of the secondary peak is q2, the block copolymer or its The ratio (q2 / q1) between q1 and q2 of the hydrogenated product (a) is in the range of 1.6 to 1.8, and the ratio (q2 / q1) between q1 and q2 in the resin composition is 1.9. It is in the range of ~ 2.1.
The one-dimensional scattering curve of the block copolymer or its hydrogenated product (a) is a curve obtained by performing small-angle X-ray scattering using (a) as a sample.

  Generally, a block copolymer containing a polymer block (A) mainly composed of a vinyl aromatic compound and a polymer block (B) mainly composed of a conjugated diene compound, which is the component (a) in the present invention. Alternatively, in the hydrogenated product, a polymer block chain mainly composed of a vinyl aromatic compound and a polymer block chain mainly composed of a conjugated diene compound are not compatible with each other, and each block chain aggregates to form a microscopic structure. It is known that domains are formed and arranged in a body-centered cubic lattice or hexagonal packing to form a higher-order structure, and so-called microphase separation structures such as spheres, cylinders, gyroids, and lamellas are formed.

  A one-dimensional scattering curve of small-angle X-ray scattering usually has a secondary peak at a scattering vector value shifted by a specific ratio q2 / q1 with respect to the primary peak corresponding to the microphase separation structure. For example, in the case of a cylinder structure filled with hexagons, there is a secondary peak at a position (q2 / q1) = √3 from the primary peak, and in the case of a lamellar structure, the ratio (q2 / q1) = from the primary peak. It is known to have a secondary peak at position 2.

  When having the above-mentioned feature (B1), the block copolymer or its hydrogenated product (a) is a cylindrical microphase separation structure (hereinafter referred to as “a microphase separation structure filled with hexagonal microphase separation structures observed by small-angle X-ray scattering”). hex-cyl "), the resin composition of the present invention containing the styrene-containing oligomer (b) together with the component (a) has a lamellar microphase separation structure (hereinafter also referred to as" lamella "). It is formed). Such a phase structure is observed in Examples 3 to 5 described later.

  That is, in this embodiment, the block phase or the hydrogenated product (a) has a polystyrene phase chain (polymer block chain mainly composed of a vinyl aromatic compound) that forms a cylinder phase in the microphase separation structure. The styrene-containing oligomer (b) is selectively compatible with the polystyrene domain and the abundance ratio increases, resulting in a structural phase transition. In the resin composition, it is inferred that the micro phase separation structure formed lamella. Further, it is presumed that the micro phase separation structure is lamella, which contributes to improvement of mechanical properties such as elastic modulus, particularly improvement of compression set.

  In addition, depending on the abundance ratio of the polystyrene domain, the microphase separation structure of the component (a) may not be hex-cyl, or the resin composition may not be lamella, but the microphase separation structure of the resin composition is lamella. Even when different from the above, the styrene-containing oligomer (b) is compatible with the polystyrene domain, which is the hard segment of the component (a), thereby exerting a reinforcing effect on the physical cross-linking point, and the resulting resin composition An improvement in the elastic modulus of the object is observed.

  The microphase-separated structure can be measured by a small angle X-ray scattering method (Small Angle X-ray Scattering; hereinafter also referred to as “SAXS”). The SAXS measurement can be performed using a general small-angle X-ray scattering measurement apparatus, and for example, can be measured using a NANO-Viewer manufactured by Rigaku Corporation. Further, the same measurement can be performed using a synchrotron radiation facility such as a polymer dedicated beam line BL03XU installed in the large synchrotron radiation facility SPring-8 (Hyogo Prefecture).

  The resin composition of the present invention has a melt flow rate (MFR) under a load of 2.16 kg at 230 ° C. measured in accordance with ASTM D1238 is usually 0.01 g / 10 min or more, preferably 0.05 to 10 g. / 10 minutes, more preferably 0.1 to 2.0 g / 10 minutes.

  The elastic modulus of the molded body formed from the resin composition of the present invention is preferably 80 MPa or more, more preferably 100 MPa or more, and CS (compression set) is preferably 40% or less, more preferably 38% or less, More preferably, it is 30% or less. These measurement conditions are as described in the examples.

Production Method of Resin Composition The resin composition of the present invention can be produced by kneading each component by a conventionally known method. The kneading is performed after the mixing step or without the mixing step. The mixing step may be performed by mixing the components of the composition simultaneously or sequentially, for example, mixing with a plastmill, a Henschel mixer, a V-blender, a ribbon blender, a tumbler blender, a kneader, a kneader ruder, etc. can do. The kneading can be produced by adopting a method of granulation, molding or pulverization after melt kneading with a single screw extruder, twin screw extruder, plast mill, kneader, kneader ruder, Banbury mixer or the like. In the kneading, the components of the composition may be charged simultaneously into the kneading part or sequentially, and the mixture having undergone the above-described mixing step may be charged all at once.

<Use of resin composition>
The above-described resin composition of the present invention can be appropriately molded by a conventionally known method and used as a molded body. Examples of the molding method include injection molding, various extrusion moldings, compression molding, calendar molding, and vacuum molding. Moreover, it can be foamed by a known method using a known chemical foaming agent at the time of molding or a known physical foaming agent such as carbon dioxide gas, nitrogen gas, water, etc., to obtain a foamed molded product.

  The resin composition can be used in combination with a support made of a hard resin or metal. There is no restriction | limiting in particular as hard resin, Engineering plastics, such as polyolefin, such as polypropylene, polyethylene, and polybutene, polyamide, polycarbonate, polyethylene terephthalate, polyacetal, polyphenylene ether, polybutylene terephthalate, polysulfone, a polyimide, can be used. The metal is not particularly limited, and is appropriately selected from, for example, a cold-rolled steel sheet, a galvanized steel sheet, an aluminum / zinc alloy-plated steel sheet, a stainless steel sheet, an aluminum plate, an aluminum alloy plate, a magnesium plate, and a magnesium alloy plate. Can be used. Moreover, what injection-molded magnesium can also be used.

  As a method of combining the resin composition with the support, a conventionally known molding method such as injection molding or extrusion molding can be employed. Although not particularly limited, for example, a hard resin to be a support is melt-injected into a mold, and the resin composition of the present invention is melt-injected and laminated on the surface of the obtained hard resin molding. Thus, an injection two-color molding method can be adopted. Alternatively, first, after a hard resin is melt-injected into a mold, the molded product is inserted into another mold, and the resin composition of the present invention is melt-injected and molded onto the surface of the plastic molded product. An insert molding method in which the resin composition is laminated and integrated on the surface can be employed. Alternatively, a metal support can be inserted into a mold, the resin composition of the present invention can be melt injection molded on the surface, and the resin composition can be laminated on the surface of the plastic molded product. Or the extrusion two-color molding which extrudes a support body and the resin composition of this invention in a multilayer shape simultaneously with the molding machine which has a some extruder can be employ | adopted. Or the molded object obtained from a resin composition can also be fixed to the surface of a support body using various adhesives.

Applications of the resin composition of the present invention include automobiles, medical / food, industry, miscellaneous goods / daily necessities.
In automotive applications, door cushion rubber, trim, door trim skin, glass channel, edges, door switch cover, bumper molding, door molding, belt molding, wind molding, roof molding, roof antenna cover, cowl looper protector, side molding, Fender liner, belt molding, mudguard, weather seal, air intake hose, B pillar seal, QW molding, seal fender apron, headlamp seal breathing cap, gaskets, tube, grommet, wire harness, opening trim, airbag cover, change Lever boot, airbag cover, air filter packing, side brake grip, shift knob, armrest, front end grille, instrument panel skin, Assist Grip, control panel switch, air bag cover, cup holder grip, shift grip, armrest cover, seat back board, console BOX insole, key cylinder bezel, B Piraroa skin, center console skin material, lamp peripheral parts, and the like.

  For medical and food applications, medical tubes, caps, syringe gaskets, toothpaste, earplugs, drug plugs, various medical plugs, dust masks, food tubes, sheets, containers rubber plugs, packing for food containers, bottle caps, etc. Examples include liners, nipples for baby bottles, and ice trays.

In industrial applications, waterproof sheets, building material sheets, hoses, grips, packing parts for automobiles and electrical products, iron core protection members, insulating covers, various gaskets for construction, and the like can be mentioned.
For miscellaneous goods and daily necessities, toothbrush grip, razor grip, bicycle grip, bath lid, knife grip, hanger member, shoulder pad, garden hose, sink hose, shampoo brush, mop, packing, health goods, sucker, binoculars, toys, daily necessities , Shoe soles, pen grips, golf grips, electric shaver grips, electric tool grips, golf ball skins, swimming goggles, jump ropes, ski stocks, diving equipment, pool mats, anti-vibration rubber, leg rubber, furniture and building parts, etc. Can be mentioned.

  Other applications include speaker edges, home appliance packing, electric tools, dampers, toner parts of ink jet printers, printer roller parts, IC holder packings, water supply / drainage packings, drainage pipe joints, and the like.

  Among the above-mentioned uses, it is preferably used for injection molded articles, sealing materials, packing materials, and cap liners. The sealing material, packing material, and cap liner are formed using the above-described resin composition of the present invention. The injection-molded article, sealing material, packing material, and cap liner according to the present invention may be formed only from the resin composition of the present invention, and are formed by combining the resin composition of the present invention and other materials. It may be.

  The resin composition of the present invention and the injection-molded article, sealing material, packing material, and cap liner formed from the resin composition are food container materials, medical materials, infant / infant products, electric / electronic parts, adhesives Applicable to a wide range of applications such as chemicals, daily necessities, and automotive interior materials.

EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.
In the following examples and comparative examples, each physical property was measured or evaluated by the following method.

<Analysis of block copolymer or hydrogenated product (a) thereof>
The weight average molecular weight (Mw) was measured using a liquid chromatograph: Waters ALC / GPC 150-C plus type (differential refractometer detector integrated type), and Tosoh Corporation GMH6-HT × 2 and GMH6-HTL as columns. × 2 were connected in series, and o-dichlorobenzene was used as a mobile phase medium, and the flow rate was 1.0 ml / min and measurement was performed at 140 ° C.

  Mw value was computed by analyzing the obtained chromatogram by the well-known method using the calibration curve which uses a standard polystyrene sample. The measurement time per sample was 60 minutes.

<Analysis of styrene-containing oligomer (b)>
[Melt viscosity at 160 ° C.]
Using a Brookfield digital viscometer, the sample amount was about 8 g and the measurement temperature was 160 ° C.

[Content of styrene structural unit]
As described in the method for producing the styrene-containing oligomer (b), examples of the method for producing the styrene-containing oligomer (b) in the present invention include the following methods (1) and (2).

(1) A method of obtaining the above (b) by copolymerizing styrene as a raw material with other monomers.
(2) A method of obtaining the above (b) by graft-modifying olefin wax with styrene.

Below, the definition of the content rate of each styrene structural unit of (1) and (2) is described.
(1) Ratio of styrene feed amount to total monomer feed amount during polymerization (2) Ratio of styrene to the total amount of olefinic wax, styrene, and vinyl aromatic compound other than styrene used as necessary. Softening point]
It was measured by the ring and ball method defined in JIS K2207.
[Glass-transition temperature]
A sample heated to 200 ° C. was cooled and crystallized to −20 ° C. at a rate of 10 ° C./min, and a DSC curve when the temperature was raised again at a rate of 10 ° C./min was analyzed with reference to JIS K7121.
[Iodine number]
Determined by titration method.

<Analysis and evaluation of resin composition>
[Melt flow rate (MFR)]
Based on ASTM D1238, measurement was performed at 230 ° C. under a load of 2.16 kg.
[Elastic modulus]
Based on JIS K-7113-2-1 / 2, a tensile test was performed under the conditions of a measurement temperature of 23 ° C. and a test speed of 50 mm / min, and the elastic modulus was measured.
[CS (compression set)]
Based on JIS K-6262, it measured on 23 degreeC, 22 hours, and the compression amount of 25% conditions.
[Small angle X-ray scattering]
(measuring device)
The SAXS measurement was performed using a NANO-Viewer manufactured by Rigaku Corporation.
(Measurement condition)
The sample was fixed to the sample holder, and SAXS measurement was performed under the following conditions.
・ Incoming X-ray: CuKα ray ・ Output: 40 kV, 30 mA
・ Detector: PILATUS 100K
・ Measurement temperature: Room temperature

[Production Example 1] Production of α-methylstyrene / styrene copolymer (b-1) A mixture of α-methylstyrene, styrene and dehydrated and purified toluene (volume ratio: 1 volume) in an autoclave having an actual capacity of 1270 ml equipped with a stirring blade. Monomer total / toluene = 1/1) and boron trifluoride phenolate complex (phenol 1.7 times equivalent) diluted 10-fold with dehydrated and purified toluene, and the reaction temperature at 5 ° C. A polymerization reaction was performed. The mass ratio of α-methylstyrene to styrene (α-methylstyrene / styrene) was 63/37, the feed rate of the monomer and toluene mixture was 1.0 liter / hour, and the feed rate of the diluted catalyst was 75. Milliliter / hour. Subsequently, after the reaction mixture was transferred to the second stage autoclave and the polymerization reaction was continued at 5 ° C., the total residence time in the first and second stage autoclaves was 2 hours. The reaction mixture was continuously discharged, and 1 liter of the reaction mixture was collected when the residence time was three times the residence time, and the polymerization reaction was terminated. After completion of the polymerization, 1N NaOH aqueous solution was added to the collected reaction mixture to deash the catalyst residue. Further, the obtained reaction mixture was washed 5 times with a large amount of water, and then the solvent and the unreacted monomer were distilled off under reduced pressure using an evaporator to obtain an α-methylstyrene / styrene copolymer (b-1). The α-methylstyrene / styrene copolymer (b-1) obtained had a softening point of 137 ° C. The other analysis results are shown in Table 1.

[Production Example 2] Production of olefin-based wax (b-3) graft-modified with styrene 240 g of ethylene / α-olefin copolymer (High Wax (trademark) 110P manufactured by Mitsui Chemicals, Inc.) was charged into a glass reactor, It was melted at 160 ° C. in a nitrogen atmosphere. Subsequently, 360.0 g of styrene and 30.2 g of di-t-butyl peroxide (hereinafter abbreviated as “DTBPO”) were continuously supplied to the reaction system (temperature of 160 ° C.) over 5 hours. Thereafter, the mixture is further reacted by heating for 1 hour, and then degassed in a 10 mmHg vacuum for 0.5 hours to remove volatile components in the molten state, and then cooled to obtain a styrene-modified olefin wax (b-3). It was.

[Each component used in Examples and Comparative Examples]
In the examples and comparative examples, the components used are as follows.
a-1: Polystyrene-poly (ethylene / butylene) -polystyrene block copolymer (SEBS) (Septon (trademark) 8007L, manufactured by Kuraray Co., Ltd., content ratio of styrene structural unit: 30% by mass, Mw = 90,000 )
a-2: Polystyrene-poly (ethylene / butylene) -polystyrene block copolymer (SEBS) (Septon (trademark) 8104, manufactured by Kuraray Co., Ltd., content ratio of styrene structural unit: 60% by mass)
b-1: α-methylstyrene / styrene copolymer obtained in Production Example 1 b-2: Hydrogenated petroleum resin (Arcon (trademark) P125, manufactured by Arakawa Chemical Industries, Ltd.)
b-3: Styrene-modified olefin wax obtained in Production Example 2 b-4: Ethylene / α-olefin copolymer (High Wax (trademark) 110P manufactured by Mitsui Chemicals, Inc.)
c-1: Homopolypropylene (manufactured by Prime Polymer Co., Ltd., Prime Polypro ™ E111G, measured in accordance with ASTM D1238, 230 ° C., melt flow rate (MFR) under a load of 2.16 kg = 0.5 g / 10 Min)

[Example 1]
As the block copolymer or its hydrogenated product (a), 100 parts by mass of polystyrene-poly (ethylene / butylene) -polystyrene block copolymer (SEBS) (a-1) is used, and the styrene-containing oligomer (b) As an example, 3 parts by mass of α-methylstyrene / styrene copolymer (b-1) was used. These are blended, using a lab plast mill (biaxial batch type melt blending device) manufactured by Toyo Seiki Seisakusho Co., Ltd., at a set temperature of 200 ° C., a resin charge amount of 50 g (device batch volume = 60 cm ³ ), 50 rpm, 5 Melt kneading was carried out under the condition of minutes. The obtained resin composition was press-molded under conditions of preheating at 200 ° C. for 5 minutes, pressure at 200 ° C. for 3 minutes, and cooling at 20 ° C. for 5 minutes, and a sheet-shaped resin composition having a thickness of 2 mm (molded product) Got. Various physical properties were measured using this. The results are shown in Table 2. A one-dimensional scattering curve of small-angle X-ray scattering is shown in FIG.

[Examples 2 to 5, Comparative Examples 1 to 3]
Except having changed the kind of component to mix | blend and quantity ratio as Table 2, it melt-kneaded similarly to Example 1, and press-molded, and obtained the sheet-like resin composition (molded object) of thickness 2mm. . Various physical properties were measured using this. The results are shown in Table 2. Moreover, the one-dimensional scattering curve of the small angle X-ray scattering of Examples 2-5 and Comparative Examples 1-2 is shown in FIG.

[Example 6]
As block copolymer or its hydrogenated product (a), polystyrene-poly (ethylene / butylene) -polystyrene block copolymer (SEBS) (a-1) 100 parts by mass, styrene-containing oligomer (b), (b -3) 4.3 parts by mass was used, and 43 parts by mass of homopolypropylene (c-1) was used as the polyolefin resin (c). These are blended, using a lab plast mill (biaxial batch type melt blending device) manufactured by Toyo Seiki Seisakusho Co., Ltd., at a set temperature of 200 ° C., a resin charge amount of 50 g (device batch volume = 60 cm ³ ), 50 rpm, 7 Melt kneading was carried out under the condition of minutes. (B-3) was added 2 minutes after kneading (a-1) and (c-1). The obtained resin composition was press-molded under preheating conditions of 200 ° C. for 7 minutes, pressure of 200 ° C. for 3 minutes, and cooling at 20 ° C. for 5 minutes, and a sheet-shaped resin composition having a thickness of 2 mm (molded product). Got. Various physical properties were measured using this. The results are shown in Table 3.

[Comparative Examples 4 to 5]
Except having changed the kind of component to mix | blend and quantity ratio as Table 3, it melt-kneaded similarly to Example 6, and press-molded, and obtained the sheet-like resin composition (molded object) of thickness 2mm. . Various physical properties were measured using this. The results are shown in Table 3.

  It turns out that Examples 1-5 are excellent in the elastic modulus compared with the comparative example 1. Moreover, especially about Examples 3-5, it turns out that CS (compression permanent set) is small with respect to the comparative example 1, and is excellent in sag-proof property. Although Comparative Example 2 is superior to Comparative Example 1 in terms of compression set, it can be seen that the elastic modulus has greatly decreased.

  From the result of small angle X-ray scattering, q2 / q1 of polystyrene-poly (ethylene / butylene) -polystyrene block copolymer (SEBS) (a-1) is 1.7, which is observed by small angle X-ray scattering. It can be seen that the microphase separation structure is formed into a cylindrical microphase separation structure with hexagonal packing (Comparative Example 1). On the other hand, in Examples 3-5, q2 / q1 of a resin composition is 2.0, and it turns out that the lamellar micro phase separation structure is formed.

Comparative Example 3 is an example in which ((A) + (b)) parts by mass with respect to ((a) + (b)) 100 parts by mass is equivalent to Example 4 but does not contain the component (b). Although the compression set is superior to that of Comparative Example 1, the elastic modulus is significantly inferior.
It can be seen that Example 6 containing the component (c) and the component (b) has a higher elastic modulus than the comparative examples 4 and 5 which contain the component (c) but do not contain the component (b).

Claims (15)

With respect to 100 parts by mass of a block copolymer containing a polymer block (A) mainly composed of a vinyl aromatic compound and a polymer block (B) mainly composed of a conjugated diene compound or a hydrogenated product thereof (a) ,
1-20 parts by mass of a styrene-containing oligomer (b) having the following features (A1) and (A2), and a melt flow rate (MFR) under a load of 2.16 kg at 230 ° C. measured according to ASTM D1238. Resin composition containing 0.1 to 500 g / 10 min polyolefin resin (c) 0 to 100 parts by mass:
(A1) The melt viscosity at 160 ° C. is 10 to 150,000 mP · s;
(A2) The content rate of the structural unit derived from styrene is 10-70 mass%.   The resin composition according to claim 1, comprising 6 to 16 parts by mass of the styrene-containing oligomer (b) with respect to 100 parts by mass of the block copolymer or a hydrogenated product (a) thereof.   The resin according to claim 1 or 2, wherein in the block copolymer or a hydrogenated product (a) thereof, the block copolymer contains the polymer block (A) in a range of 20 to 40% by mass. Composition.   When the total of the block copolymer or its hydrogenated product (a) and the styrene-containing oligomer (b) is 100 parts by mass, the total mass of the polymer block (A) and the (b) is The resin composition as described in any one of Claims 1-3 which exists in the range of 34-66 mass parts.   When the total of the block copolymer or its hydrogenated product (a) and the styrene-containing oligomer (b) is 100 parts by mass, the total mass of the polymer block (A) and the (b) is The resin composition as described in any one of Claims 1-3 which exists in the range of 34-50 mass parts. The resin composition according to any one of claims 1 to 5, wherein the styrene-containing oligomer (b) further has one or more of the following characteristics (A3) to (A6):
(A3) 50-70 parts by mass of a structural unit derived from α-methylstyrene and 30-50 parts by mass of a structural unit derived from styrene (however, a structural unit derived from α-methylstyrene and a structural unit derived from styrene) The total is 100 parts by mass);
(A4) the softening point is in the range of 80-150 ° C;
(A5) The glass transition temperature (Tg) measured with a differential scanning calorimeter (DSC) is in the range of 0 to 100 ° C .;
(A6) iodine value is in the range of 100g_I ₂ / 100g.   The styrene-containing oligomer (b) is a styrene-modified product of a copolymer of ethylene and at least one α-olefin selected from α-olefins having 3 to 12 carbon atoms. The resin composition as described in any one. Furthermore, the resin composition as described in any one of Claims 1-7 which has the characteristic of the following (B1):
(B1) One-dimensional scattering curve for small-angle X-ray scattering (the horizontal axis is the size of the scattering vector q (where q = (4π / λ) sin (θ / 2), where X-ray wavelength is λ, θ is the scattering angle) And the vertical axis represents the logarithm of the scattering intensity I (q), and when the q value of the primary peak is q1 and the q value of the secondary peak is q2,
The ratio (q2 / q1) of q1 and q2 of the block copolymer or its hydrogenated product (a) is in the range of 1.6 to 1.8, and the ratio of q1 and q2 in the resin composition ( q2 / q1) is in the range of 1.9 to 2.1.   The resin composition according to any one of claims 1 to 8, wherein the polyolefin resin (c) is a polypropylene resin.   The resin composition according to any one of claims 1 to 9, further comprising 5 to 300 parts by mass of oil with respect to 100 parts by mass in total of the components (a), (b), and (c).   The resin composition according to any one of claims 1 to 10, further comprising 5 to 20 parts by mass of a filler with respect to a total of 100 parts by mass of the components (a), (b) and (c).   The molded object which consists of a resin composition of any one of Claims 1-11.   The sealing material which consists of a resin composition of any one of Claims 1-11.   The packing material which consists of a resin composition of any one of Claims 1-11.   The cap liner which consists of a resin composition of any one of Claims 1-11.