JP6472270B2 - Thermoplastic elastomer composition and molded article thereof - Google Patents

Description

  The present invention relates to an olefinic thermoplastic elastomer composition, and more particularly to an olefinic thermoplastic elastomer composition having a good balance between mechanical properties and rubber elasticity and a molded article thereof.

  Olefin-based thermoplastic elastomers are lightweight and easy to recycle, and do not generate toxic gases during incineration, so they are energy and resource savings. Widely used in automobile parts, industrial machine parts, electrical / electronic parts, building materials, etc. However, conventional olefin-based thermoplastic elastomers generally have the disadvantage of being inferior in rubber elasticity compared to vulcanized rubber, and there has been a strong demand for improvement. In particular, it has been technically difficult to achieve both rubber elasticity at low and high temperatures.

  It is known that a mineral oil softener is added to the thermoplastic elastomer for the purpose of increasing flexibility and rubber elasticity.

  However, when an olefinic thermoplastic elastomer compounded with a mineral oil softener is used for automobile interior materials, etc., there is a problem that a fogging phenomenon (a phenomenon in which the glass becomes cloudy) occurs when used for a long time. Improvement was desired.

  As an olefinic thermoplastic elastomer composition excellent in fogging resistance, Patent Document 1 discloses that a crystalline polyolefin, an olefinic copolymer rubber, and an evaporation loss at 200 ° C. under normal pressure for 1 hour are 0.4 weight. %, And an olefinic thermoplastic elastomer composition comprising a paraffinic mineral oil softener having a kinematic viscosity at 40 ° C. of 50 to 250 cSt is disclosed.

  Patent Document 2 discloses blending a mixture of refined mineral oil and synthetic oil as a softening agent with an olefinic thermoplastic elastomer composition.

  Although the volatile content in the mineral oil varies depending on the degree of purification, generally, the lower the viscosity of the mineral oil, the lower the molecular weight component increases, so the volatile content increases and the fogging resistance tends to deteriorate.

Therefore, in the composition described in Patent Document 1, a mineral oil having a kinematic viscosity at 40 ° C. of 50 cSt or more is used. Patent Document 2 describes that the kinematic viscosity of mineral oil at 40 ° C. is preferably 400 mm ² / s or less (400 cSt or less), but the refined mineral oil used in the examples at 40 ° C. The kinematic viscosity is 99 mm ² / s (99 cSt). In Patent Document 2, in order to particularly improve the fogging resistance, in the examples, synthetic oil having a high degree of purification is used, and the synthetic oil has an ethylene content of 73 mol% and a number average molecular weight of 7500 (polystyrene conversion). An ethylene / propylene random copolymer, whose viscosity is considered to be higher than that of mineral oil, is used. However, nothing is mentioned about the relationship between the kinematic viscosity correlated with the ethylene content and the number average molecular weight of the synthetic oil, and the rubber elasticity at high and low temperatures.

European Patent Application No. 1123946 International Publication No. 2007/060843

  An object of the present invention is to provide a thermoplastic elastomer composition having excellent fogging resistance and excellent balance between mechanical properties such as strength and elongation and rubber elasticity (compression set) at low and high temperatures. .

The gist of the present invention is as follows.
(1) Ethylene / α-olefin / non-conjugated polyene copolymer (A) 90 to 10 parts by weight, olefin-based resin (B) 10 to 90 parts by weight, and (A) and (B) total amount 100 parts by weight On the other hand, a mixture containing 3 to 100 parts by weight of the ethylene / α-olefin copolymer (C) satisfying the following requirements (i) to (vi) is dynamically heat-treated in the presence of a crosslinking agent. Thermoplastic elastomer composition.
(I) It has a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms.
(Ii) The content of structural units derived from ethylene is 30 to 70 mol% (provided that the total of the content of structural units derived from ethylene and the content of structural units derived from α-olefins is 100 mol%) ).
(Iii) The intrinsic viscosity [η] measured in decalin at 135 ° C. is 0.01 to 0.50 dl / g.
(Iv) The kinematic viscosity at 100 ° C. is 10 to 5,000 mm ² / s.
(V) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 1.0 to 3.0.
(Vi) The glass transition temperature (Tg) determined by differential scanning calorimetry (DSC) is -90 to -65 ° C.
(2) The thermoplastic elastomer composition according to (1), wherein the ethylene / α-olefin copolymer (C) has a kinematic viscosity at 100 ° C. of 10 to 2,500 mm ² / s.
(3) One type in which the olefin resin (B) is selected from homopolypropylene, a random copolymer of α-olefin other than propylene and propylene, and a block copolymer of α-olefin other than propylene and propylene The thermoplastic elastomer composition according to (1) or (2), which is the above propylene polymer.
(4) The thermoplastic elastomer composition according to any one of (1) to (3), wherein the crosslinking agent is an organic peroxide.
(5) The thermoplastic elastomer composition according to any one of (1) to (3), wherein the crosslinking agent is a phenol resin.
(6) A molded product obtained by molding the thermoplastic elastomer composition according to any one of (1) to (5).
(7) The molded product according to (6), which is an automobile interior part.

  According to the present invention, it is possible to provide a thermoplastic elastomer composition having excellent fogging resistance and excellent balance between mechanical properties such as strength and elongation and rubber elasticity (compression set) at low and high temperatures. .

  The thermoplastic elastomer composition of the present invention comprises an ethylene / α-olefin / non-conjugated polyene copolymer (A) 90 to 10 parts by weight, an olefin resin (B) 10 to 90 parts by weight, and (A) and (B ) Is obtained by dynamically heat-treating a mixture containing 3 to 100 parts by weight of an ethylene / α-olefin copolymer (C) having specific physical properties with respect to 100 parts by weight of the total amount of .

[Ethylene / α-olefin / non-conjugated polyene copolymer (A)]
The ethylene / α-olefin / nonconjugated polyene copolymer (A) used in the present invention is ethylene, an α-olefin other than ethylene, preferably an α-olefin having 3 to 20 carbon atoms, and a nonconjugated polyene, preferably Is a copolymer comprising a non-conjugated diene.

  The copolymer (A) can be produced by using “polymer manufacturing process (Industry Research Institute, Inc., p. 309-330)” or Japanese Patent Application Laid-Open No. 9-71617 and Japanese Patent Application Laid-Open No. 9-71618 according to the applicant's application. No. 9, JP-A-9-208615, JP-A-10-67823, JP-A-10-67824, JP-A-10-110054, WO2009 / 081792 pamphlet, WO2009 / 081794 pamphlet and the like. Can be produced by a conventionally known method.

As an olefin polymerization catalyst preferably used in the production of the ethylene / α-olefin / non-conjugated polyene copolymer (A) used in the present invention, for example,
A known Ziegler catalyst comprising a transition metal compound such as vanadium (V), zirconium (Zr), titanium (Ti) and the like, and an organoaluminum compound (organoaluminum oxy compound);
A known metallocene catalyst comprising a metallocene compound of a transition metal selected from Group 4 of the periodic table of elements and an organoaluminum oxy compound or an ionized ionic compound, for example, a metallocene catalyst described in JP-A-9-40586 ;
A known metallocene catalyst comprising a specific transition metal compound and a cocatalyst such as a boron compound, for example, a metallocene catalyst described in WO2009 / 072553;
A transition metal compound catalyst comprising a specific transition metal compound and an organometallic compound, an organoaluminum oxy compound, or a compound that reacts with the transition metal compound to form an ion pair, such as described in JP 2011-52231 A Transition metal compound catalysts;
Is mentioned. In particular, a metallocene catalyst is particularly preferable because the distribution of diene is uniform and high crosslinking efficiency can be obtained even if the introduction of diene is small, and the catalyst-derived chlorine content can be reduced because of high catalytic activity.

  The ethylene / α-olefin / non-conjugated polyene copolymer (A) used in the present invention is a total of 100 mol of a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms. %, The content of structural units derived from ethylene (Ea mol%) is usually 40 to 90 mol%, preferably 40 to 80 mol%, more preferably 45 to 70 mol%, still more preferably 50 to The content of structural units derived from an α-olefin having 3 to 20 carbon atoms is usually 60 to 10 mol%, preferably 60 to 20 mol%, more preferably 55 to 30 mol%, Preferably it is 50-40 mol%.

When the content of the structural unit derived from ethylene and the content of the structural unit derived from the α-olefin having 3 to 20 carbon atoms are within the above ranges, the mechanical properties, rubber elasticity, cold resistance and processability are excellent. It is excellent in that a thermoplastic elastomer composition can be obtained. When the content of the structural unit derived from ethylene is 90 mol% or less and the content of the structural unit derived from the α-olefin having 3 to 20 carbon atoms is 10 mol% or more, the thermoplastic composition is flexible and low in temperature. Excellent rubber elasticity and processability. When the content of the structural unit derived from ethylene is 40 mol% or more and the content of the structural unit derived from the α-olefin having 3 to 20 carbon atoms is 60 mol% or less, the thermoplastic composition has mechanical properties and high temperature. Excellent rubber elasticity. The ethylene structural unit content of the ethylene / α-olefin / non-conjugated polyene copolymer (A) and the content of the α-olefin structural unit can be measured by a ¹³ C-NMR method. And identification and quantification of peaks can be performed according to the method described in “Polymer Analysis Handbook” (Asakura Shoten 2008, first edition, P184-211).

  Specific examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 4-methylpentene-1, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-nonadecene, 1-eicosene, 9-methyldecene-1, 11-methyldodecene- 1,12-ethyltetradecene-1 etc. are mentioned. Among these, propylene, 1-butene, 4-methylpentene-1, 1-hexene and 1-octene are preferable, and propylene is particularly preferable. These α-olefins are used alone or in combination of two or more.

  Specific examples of the non-conjugated polyene include 1,4-hexadiene, 3-methyl-1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4,5 Chain unconjugated dienes such as dimethyl-1,4-hexadiene, 7-methyl-1,6-octadiene, 8-methyl-4-ethylidene-1,7-nonadiene, 4-ethylidene-1,7-undecadiene; Methyltetrahydroindene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 5-vinylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene , 5-vinyl-2-norbornene, 5-isopropenyl-2-norbornene, 5-isobutenyl-2-norbornene Cyclic non-conjugated dienes such as cyclopentadiene and norbornadiene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,2-norbornadiene, 4-ethylidene And triene such as -8-methyl-1,7-nonadiene. Of these, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, cyclopentadiene, and 4-ethylidene-8-methyl-1,7-nonadiene are preferable.

  The ethylene / α-olefin / non-conjugated polyene copolymer (A) according to the present invention has an intrinsic viscosity [η] measured in decalin at 135 ° C. of usually 0.6 to 5.0 dl / g, preferably 0. It is desirable that it is 0.8 to 4.0 dl / g, more preferably 0.9 to 3.5 dl / g. When the intrinsic viscosity [η] measured in decalin at 135 ° C. is in this range, it is excellent in that a thermoplastic elastomer having an excellent balance of mechanical properties, rubber elasticity and processability can be obtained.

  The iodine value of the ethylene / α-olefin / non-conjugated polyene copolymer (A) according to the present invention is usually 2 to 50 g / 100 g, preferably 5 to 40 g / 100 g, more preferably 7 to 30 g / 100 g. Is desirable. When the iodine value is below this range, the crosslinking efficiency in the thermoplastic elastomer is lowered and the rubber elasticity is lowered. If the iodine value exceeds this range, the crosslink density becomes too high, the elongation may decrease, and the physical property balance may deteriorate.

  The ethylene / α-olefin / non-conjugated polyene copolymer (A) according to the present invention has a molecular weight distribution (Mw / Mn) measured by GPC of usually 1.5 to 50, preferably 1.8 to 30. More preferably, it is 2.0-6. When the molecular weight distribution is below this range, the content of low molecular weight components decreases, and the processability decreases. When the molecular weight distribution exceeds this range, the content of low molecular weight components increases and the fogging resistance deteriorates.

The Mooney viscosity [ML _{1 + 4} (100 ° C.)] of the ethylene / α-olefin / non-conjugated polyene copolymer (A) according to the present invention is preferably 15 to 150. When the Mooney viscosity is within this range, the balance between mechanical properties and processability is excellent.

  The ethylene / α-olefin / non-conjugated polyene copolymer (A) according to the present invention preferably has a heat of fusion of 60 J / g or less measured by a method described later with a differential scanning calorimeter (DSC). / G or less is more preferable, and 20 J / g or less is particularly preferable. When the heat of fusion is 60 J / g or less, the flexibility and rubber elasticity are excellent.

  The copolymer (A) can exist in all cross-linked states such as uncrosslinked, partially cross-linked, and fully cross-linked in the thermoplastic elastomer, but in the present invention, it exists in a completely or partially cross-linked state. It is necessary to be.

[Olefin resin (B)]
The olefin resin (B) used in the present invention is usually composed of a high molecular weight solid product obtained by polymerizing one or more monoolefins by a high pressure method or a low pressure method. These representative resins are commercially available.

  The suitable raw material olefin of the olefin-based resin (B) is preferably an α-olefin having 2 to 20 carbon atoms, specifically ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-hexene, Examples include octene, 1-decene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 5-methyl-1-hexene. These olefins are used alone or in combination of two or more. The polymerization mode may be random type or block type as long as a resinous material is obtained. Further, the stereoregularity may be an isotactic structure or a syndiotactic structure. These olefin resins may be used alone or in combination of two or more.

  The olefin resin (B) used in the present invention is preferably a propylene polymer having a propylene content of 40 mol% or more, more preferably a propylene content of 60 mol% or more, more preferably 80 mol% or more, particularly Preferably it is 90 mol% or more.

  Among these olefin resins, propylene polymers, specifically, homopolypropylene, random copolymers of propylene and α-olefins other than propylene (for example, propylene / ethylene random copolymers, propylene / ethylene · Butene random copolymers) and one or more propylene polymers selected from block copolymers of propylene and α-olefins other than propylene (for example, propylene / ethylene block copolymers) are particularly preferred.

  The olefin resin (B) used in the present invention is not particularly limited in intrinsic viscosity [η] measured in decalin at 135 ° C., but is preferably 0.6 dl / g or more and 5 dl / g or less. is there. When the intrinsic viscosity [η] measured in decalin at 135 ° C. decreases, the mechanical strength of the thermoplastic elastomer decreases. As the intrinsic viscosity [η] increases, the moldability deteriorates.

In the olefin resin (B) used in the present invention, MFR (ASTM D1238-65T, 230 ° C., 2.16 kg) is usually 0.01 to 100 g / 10 minutes, particularly 0.05 to 50 g / 10 minutes. Preferably there is. A polyolefin resin having an MFR of 0.01 to 100 g / 10 min has a kinematic viscosity at 100 ° C. of 20000 mm ² / s or more, and it is difficult to measure the kinematic viscosity at 100 ° C. substantially. That is, the (c) polyolefin resin according to the present invention usually has a kinematic viscosity at 100 ° C. exceeding 5000 mm ² / s.

  It is a mechanical property of the polymer composition that the melting point of the olefin resin (B) used in the present invention is 100 to 200 ° C. as measured by the heat of fusion measured by the method described later with a differential scanning calorimeter (DSC). It is preferable in terms of imparting heat resistance and ensuring molding processability. The melting point of the olefin resin (B) is more preferably 120 to 180 ° C, and still more preferably 140 to 170 ° C.

[Softener (plasticizer)]
In the present invention, an ethylene / α-olefin copolymer (C) satisfying the following requirements (i) to (vi) is used as a softener (plasticizer).
(I) It has a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms.
(Ii) The content of structural units derived from ethylene is 30 to 70 mol% (provided that the total of the content of structural units derived from ethylene and the content of structural units derived from α-olefins is 100 mol%) ).
(Iii) The intrinsic viscosity [η] measured in decalin at 135 ° C. is 0.01 to 0.50 dl / g.
(Iv) The kinematic viscosity at 100 ° C. is 10 to 5,000 mm ² / s.
(V) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 1.0 to 3.0.
(Vi) The glass transition temperature (Tg) determined by differential scanning calorimetry (DSC) is -90 to -65 ° C.

  Therefore, the thermoplastic elastomer composition of the present invention is superior in fogging resistance and has an ethylene content exceeding 70 mol% compared to an olefin thermoplastic elastomer whose main softener is a mineral oil softener. -It is excellent in rubber elasticity at low and high temperatures as compared with an olefinic thermoplastic elastomer using an olefin copolymer as a softening agent.

  The ethylene / α-olefin copolymer (C) used in the present invention is a copolymer composed of ethylene and an α-olefin having 3 to 20 carbon atoms, and does not contain polyene as a copolymerization component.

  Specific examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methylpentene-1, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-nonadecene, 1-eicosene, 9-methyldecene-1, 11-methyldodecene- 1,12-ethyltetradecene-1 etc. are mentioned. Of these, propylene, 1-butene, 4-methylpentene-1, 1-hexene, and 1-octene are preferable, and propylene is particularly preferable in terms of the balance between rubber elasticity at low temperature and high temperature. These α-olefins are used alone or in combination of two or more.

  The ethylene / α-olefin copolymer (C) used in the present invention has a content of structural units derived from ethylene of 30 to 70 mol%, preferably 30 to 65 mol%, more preferably 45 to 60 mol%. The content of the structural unit derived from the α-olefin is 70 to 30 mol%, preferably 70 to 35 mol%, more preferably 55 to 40 mol%. However, the total of the content of structural units derived from ethylene and the content of structural units derived from α-olefin is 100 mol%. If the ethylene content is too much or less than the above range, the crystallinity becomes high, and the rubber elasticity and flexibility of the thermoplastic elastomer at a low temperature may be remarkably deteriorated.

In the ethylene / α-olefin copolymer (C) used in the present invention, the content of structural units derived from ethylene and the content of structural units derived from α-olefin can be measured by ¹³ C-NMR method. For example, peak identification and quantification can be carried out according to the method described below and the method described in “Polymer Analysis Handbook” (Asakura Shoten 2008 First Edition P184-211).

  The ethylene / α-olefin copolymer (C) used in the present invention has an intrinsic viscosity [η] measured in decalin at 135 ° C. of 0.01 to 0.50 dl / g, preferably 0.01 to 0.00. 30 dl / g, more preferably 0.02 to 0.22 dl / g.

  When the intrinsic viscosity [η] measured in decalin at 135 ° C. of the ethylene / α-olefin copolymer (C) is less than 0.01 dl / g, the low molecular weight component that tends to volatilize increases and the physical properties deteriorate during molding. This causes a decrease in the heat resistance and fogging resistance of the thermoplastic elastomer and the fogging resistance. If it exceeds 0.50 dl / g, the rubber elasticity at low and high temperatures is lowered, and the handling property of the ethylene / α-olefin copolymer (C) is deteriorated.

  As one preferable aspect of the present invention, the intrinsic viscosity [η] is 0.02 to 0.10 dl / g, which is particularly preferable because of excellent balance between low and high temperature rubber elasticity and handling properties. As a different embodiment, the intrinsic viscosity [η] is 0.11 to 0.22 dl / g, which is excellent in heat resistance and fogging resistance, and is particularly preferable.

The ethylene / α-olefin copolymer (C) used in the present invention has a kinematic viscosity at 100 ° C. of 10 to 5,000 mm ² / s, preferably 10 to 3,000 mm ² / s, and more preferably. 10 to 2,500 mm ² / s.

When the kinematic viscosity at 100 ° C. of the ethylene / α-olefin copolymer (C) is less than 10 mm ² / s, the amount of low molecular weight components that are likely to volatilize increases, reducing the physical properties during molding and the heat resistance of the thermoplastic elastomer. And fogging resistance is reduced. When it exceeds 5,000 mm ² / s, the rubber elasticity at low and high temperatures is lowered and the handling property of the ethylene / α-olefin copolymer (C) is deteriorated.

As a preferred embodiment of the present invention, a kinematic viscosity at 100 ° C. of 10 to 399 mm ² / s, particularly 10 to ²⁰⁰ mm ² / s, is particularly preferred because of excellent balance between low and high temperature rubber elasticity and handling properties. As a different mode, the kinematic viscosity at 100 ° C. is 400 to 2,500 mm ² / s, which is particularly preferable because of excellent heat resistance and fogging resistance.

  The molecular weight distribution (Mw / Mn) of the ethylene / α-olefin copolymer (C) used in the present invention is 1.0 to 3.0, preferably 1.4 to 2.5. When the molecular weight distribution is wide (Mw / Mn is large), it is easy to ooze out and contains many low molecular weight components that deteriorate fogging resistance and high molecular weight components that may reduce the softening effect and workability improvement effect. This is not preferable. In addition, molecular weight distribution (Mw / Mn) is calculated | required as ratio of the weight average molecular weight (Mw) and number average molecular weight (Mn) calculated | required by gel permeation chromatography (GPC).

  The ethylene / α-olefin copolymer (C) used in the present invention has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of −90 to −65 ° C., more preferably − It exists in the range of 80-65 degreeC. If the glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) exceeds −65 ° C., the effect of lowering the glass transition temperature (Tg) of the resulting thermoplastic elastomer is reduced, which is not preferable. When an ethylene / α-olefin copolymer (C) having a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of −90 ° C. or higher is used, the glass transition temperature (Tg) of the thermoplastic elastomer obtained. The glass transition temperature (Tg) is lower than −90 ° C., which is not preferable because the molecular weight is decreased, the volatility is increased, and the fogging resistance is decreased. .

  In the present invention, the glass transition temperature (Tg) of the ethylene / α-olefin copolymer (C) is measured by differential scanning calorimetry (DSC).

The ethylene / α-olefin copolymer (C) used in the present invention is not particularly limited, but the B value determined from the ¹³ C-NMR spectrum and the following general formula (1) is usually 1. It is 0 or more, preferably 1.0 to 1.50, more preferably 1.1 to 1.4.

B value = [POE] / (2 · [PE] [PO]) (1)
(Wherein [PE] is the molar fraction of structural units derived from ethylene in the copolymer, and [PO] is the molar fraction of structural units derived from α-olefin in the copolymer. And [POE] is the ratio of the number of ethylene / α-olefin chains to the total number of dyad chains in the copolymer.)

This B value is an index that represents the distribution state of ethylene and α-olefin in the ethylene / α-olefin copolymer. JC Randall (Macromolecules, 15, 353 (1982)), J. Ray (Macromolecules, 10 , 773 (1977)).
The larger the B value, the shorter the block chain of ethylene or α-olefin, the more uniform the distribution of ethylene and α-olefin, and the narrower the composition distribution of the copolymer.

  When the B value of the ethylene / α-olefin copolymer (C) used in the present invention is smaller than 1.06, the crystallinity increases, and the rubber elasticity and flexibility of the thermoplastic elastomer at a low temperature are remarkably deteriorated. This is not preferable. Further, the ethylene / α-olefin copolymer (C) used in the present invention is not particularly limited, but the polystyrene-reduced weight average molecular weight (Mw) usually obtained by gel permeation chromatography (GPC) is usually used. 1,000 to 30,000, more preferably 2,000 to 20,000. When the weight average molecular weight is less than 1,000, low molecular weight components that are likely to volatilize increase, causing a decrease in physical properties during molding, a decrease in heat resistance and fogging resistance of the thermoplastic elastomer, and a decrease in fogging resistance. When it exceeds 30,000, the rubber elasticity at low and high temperatures is lowered, and the handling property of the ethylene / α-olefin copolymer (C) is deteriorated.

  As a preferred embodiment of the present invention, a weight average molecular weight (Mw) of 2,000 to 7,000 is particularly preferred because of excellent balance between low and high temperature rubber elasticity and handling properties. As a different embodiment, the weight average molecular weight (Mw) of 7,000 to 20,000 is particularly preferable because of excellent heat resistance and fogging resistance.

The ethylene / α-olefin copolymer (C) used in the present invention is not particularly limited, but the kinematic viscosity at 40 ° C. is preferably 10 to 50,000 mm ² / s, preferably 100 to It is 45,000 mm < ² > / s, More preferably, it is 390-40,000 mm < ² > / s.

When the kinematic viscosity at 40 ° C. of the ethylene / α-olefin copolymer (C) is less than 10 mm ² / s, the amount of low molecular weight components that are likely to volatilize increases, resulting in a decrease in physical properties during molding and a decrease in heat resistance of the thermoplastic elastomer. And fogging resistance is reduced. If it exceeds 50,000 mm ² / s, the rubber elasticity at low temperature and high temperature is lowered, and the handling property of the ethylene / α-olefin copolymer (C) is deteriorated.

As one preferred embodiment of the present invention, when the kinematic viscosity at 40 ° C. is 100 to 4,999 mm ² / s, or 390 to 4,999 mm ² / s, the rubber elasticity at low temperature and high temperature is excellent and the handling property is excellent. Is particularly preferred. As a different embodiment, a kinematic viscosity at 40 ° C. of 5,000 to 40,000 mm ² / s is particularly preferable because of excellent heat resistance and fogging resistance.

  The ethylene / α-olefin copolymer (C) used in the present invention can be produced using a known method without limitation. For example, ethylene and an α-olefin are copolymerized in the presence of a catalyst comprising a transition metal compound such as vanadium, zirconium, titanium, hafnium, and an organoaluminum compound (organoaluminum oxy compound) and / or an ionized ionic compound. A method is mentioned. Metallocene catalysts using transition metal compounds such as zirconium, titanium, and hafnium have less 2,1-bond (inversion) formed from two or more consecutive propylene monomers, and the low temperature characteristics of thermoplastic elastomers. It is preferable because it improves. Such a method is described in, for example, International Publication No. 2000/34420 pamphlet, Japanese Patent Application Laid-Open No. 62-121710, International Publication No. 2004/29062 pamphlet, Japanese Patent Application Laid-Open No. 2004-175707, International Patent Publication No. 2001/27124. Has been.

  The ethylene / α-olefin copolymer (C) may be hydrogenated (hereinafter also referred to as “hydrogenation”) by a conventionally known method. If the double bond of the polymer obtained by hydrogenation is reduced, the oxidation stability and heat resistance are improved.

  The ethylene / α-olefin copolymer (C) used in the present invention has the properties within the range satisfying the above requirements (i) to (vi) as the entire ethylene / α-olefin copolymer (C). Two or more different ethylene / α-olefin copolymers may be used in combination.

  In the ethylene / α-olefin copolymer (C), functional groups may be graft-modified, or these may be further secondary-modified. Examples of secondary modification include the method described in JP-T-2008-508402 and the like, such as the method described in JP-A-61-126120 and Japanese Patent No. 2593264.

  The ethylene / α-olefin copolymer (C) may be oil-extended into the ethylene / α-olefin / non-conjugated polyene copolymer (A), or may be added later without oil extension.

  The blending amount of the ethylene / α-olefin copolymer (C) is 3 to 3 parts by weight based on 100 parts by weight of the total amount of the ethylene / α-olefin / non-conjugated polyene copolymer (A) and the olefin resin (B). 100 parts by weight, preferably 5 to 80 parts by weight.

  In the present invention, a softener (D) other than the ethylene / α-olefin copolymer (C) may be used as long as the effects of the present invention are not impaired.

  Specifically, process oil, lubricant oil, paraffin, liquid paraffin, polyethylene wax, polypropylene wax, petroleum asphalt, petroleum softener such as petroleum jelly, coal tar softener such as coal tar and coal tar pitch, castor oil, Fat oil softeners such as linseed oil, rapeseed oil, soybean oil, coconut oil, waxes such as tall oil, sub (factis), beeswax, carnauba wax, lanolin, ricinoleic acid, palmitic acid, stearic acid, barium stearate Fatty acids and fatty acid salts such as calcium stearate and zinc laurate, naphthenic acid, pine oil, rosin or derivatives thereof, terpene resin, petroleum resin, coumarone indene resin, synthetic polymer substances such as atactic polypropylene, dioctyl phthalate, dioctyl Adipate, dioctyl Ester softeners such Baketo, microcrystalline wax, liquid polybutadiene, modified liquid polybutadiene, liquid polyisoprene, end modified polyisoprene, water 添末 end modified polyisoprene, liquid Thiokol, and a hydrocarbon-based synthetic lubricating oils. Among these, petroleum softeners, particularly process oils are preferably used.

  The blending amount of the softener (D) is usually 100 parts by weight or less, preferably 50 parts by weight or less, more preferably 100 parts by weight or less with respect to 100 parts by weight of the ethylene / α-olefin copolymer (C). 35 parts by weight or less, more preferably 10 parts by weight or less.

[Thermoplastic elastomer composition]
In the thermoplastic elastomer composition of the present invention, the blending amount of the olefin resin (B) is 100 parts by weight of the total amount of the ethylene / α-olefin / non-conjugated polyene copolymer (A) and the olefin resin (B). On the other hand, it is 10-90 weight part, Preferably it is 20-70 weight part, More preferably, it is 25-60 weight part.

  In the thermoplastic elastomer composition of the present invention, as the rubber component, in addition to the ethylene / α-olefin / non-conjugated polyene copolymer (A), other rubbers may be used in combination. The other rubber is preferably used in an amount of 50 parts by weight or less based on 100 parts by weight of the α-olefin / non-conjugated polyene copolymer (A).

  Examples of other rubbers include diene rubbers such as styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), natural rubber (NR), and butyl rubber (IIR), SEBS, and polyisobutylene.

  The thermoplastic elastomer composition of the present invention includes an ethylene / α-olefin / non-conjugated polyene copolymer (A), an olefin resin (B), an ethylene / α-olefin copolymer (C), and, if necessary. Ingredients other than the softening agent (D) blended, for example, heat stabilizers, antistatic agents, weathering stabilizers, anti-aging agents, fillers, colorants, lubricants, and the like, if necessary, It can mix | blend in the range which does not impair the objective of this invention.

  In one preferred embodiment, the ethylene / α-olefin / non-conjugated polyene copolymer (A), the olefin resin (B), and the ethylene / α-olefin copolymer are used with respect to 100 parts by weight of the elastomer composition of the present invention. Although it is mentioned to mix | blend 30 weight part or less of components other than a unification | combination (C) and the said softening agent (D), this invention is not limited to this.

  The thermoplastic elastomer composition of the present invention comprises an ethylene / α-olefin / non-conjugated polyene copolymer (A), an olefin resin (B), an ethylene / α-olefin copolymer (C), and, if necessary. It is a thermoplastic elastomer composition obtained by dynamically heat-treating a mixture containing an additive to be blended in the presence of a crosslinking agent, preferably an organic peroxide or a phenol resin.

  Specific examples of the organic peroxide used as the crosslinking agent include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2, 5-Dimethyl-2,5-di- (tert-butylperoxy) hexyne-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3 5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxyisopropyl Carbonate, diaceti Peroxide, lauroyl peroxide, etc. tert- butyl cumyl peroxide.

  Among these, in terms of odor and scorch stability, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di- (tert-butyl) Peroxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (Tert-Butylperoxy) valerate is preferred, and 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane and 1,3-bis (tert-butylperoxyisopropyl) benzene are most preferred.

  In this invention, an organic peroxide is 0.05-3 weight normally with respect to 100 weight part of total amounts of an olefin resin (B), all the rubber components, and an ethylene alpha-olefin copolymer (C). Parts, preferably 0.1 to 1 part by weight.

  In the crosslinking treatment with the organic peroxide, sulfur, p-quinonedioxime, p, p′-dibenzoylquinonedioxime, N-methyl-N-4-dinitrosoaniline, nitrosobenzene, diphenylguanidine, trimethylolpropane , N, N'-m-phenylene dimaleimide, divinylbenzene, triallyl cyanurate, or ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate Polyfunctional methacrylate monomers such as these; polyfunctional vinyl monomers such as vinyl butyrate and vinyl stearate can be blended.

By using such a compound, a uniform and mild crosslinking reaction can be expected.
Compounds such as the above-mentioned crosslinking aid or polyfunctional vinyl monomer improve the fluidity of the resulting thermoplastic elastomer and prevent changes in physical properties due to thermal history during processing and molding. In this respect, it is preferably used in a proportion of 0.1 to 2 parts by weight, particularly 0.3 to 1 part by weight, based on 100 parts by weight of the entire cross-linked product.

  The phenolic resin used as a crosslinking agent is also called a phenolic curative and refers to a vulcanizing agent containing a phenolic curing resin, preferably US Pat. No. 4,311,628. Examples thereof include a phenolic curative system composed of a phenolic curing resin and a cure activator disclosed in the specification.

Basic components of the systems are substituted phenol in an alkaline medium (e.g., halogen substituted phenol, C ₁ -C ₂ alkyl substituted phenol) or unsubstituted phenol with an aldehyde, or preferably by condensation with formaldehyde, or bifunctional phenol dialcohols (preferably, the para position is C ₅ -C ₁₀ dimethylol phenols substituted with an alkyl group) a phenolic curing resin made by condensation of. Particularly suitable are halogenated alkyl-substituted phenolic curable resins prepared by halogenation of alkyl-substituted phenolic curable resins. A phenolic vulcanizing agent system consisting of a methylolphenol curable resin, a halogen donor and a metal compound can be particularly recommended, and details thereof are described in US Pat. Nos. 3,287,440 and 3,709,840. Non-halogenated phenolic curable resins are used simultaneously with the halogen donor, preferably with a hydrogen halide scavenger. Usually, halogenated phenolic curable resins, preferably brominated phenolic curable resins containing 2 to 10% by weight of bromine, do not require a halogen donor, for example, iron oxide, titanium oxide, oxidized Used simultaneously with hydrogen halide scavengers such as magnesium, magnesium silicate, silicon dioxide and preferably metal oxides such as zinc oxide. Although the presence of such a scavenger promotes the crosslinking action of the phenolic curable resin, it is desirable to share a halogen donor and zinc oxide in the case of a rubber that is not easily vulcanized with the phenolic curable resin. The preparation of halogenated phenolic curable resins and their use in vulcanizing systems using zinc oxide are described in U.S. Pat. Nos. 2,972,600 and 3,093,613, the disclosures of which are described in U.S. Pat. Incorporated herein by reference together with the disclosure of US Pat. Nos. 3,287,440 and 3,709,840. Examples of suitable halogen donors include stannous chloride, ferric chloride, or halogen donating heavys such as chlorinated paraffin, chlorinated polyethylene, chlorosulfonated polyethylene and polychlorobutadiene (neoprene rubber). Coalesce is mentioned. As used herein, the term “activator” refers to any substance that substantially increases the crosslinking efficiency of the phenolic curable resin, and includes metal oxides and halogen donors, which are used alone. Or used in combination. For more details on phenolic vulcanizing systems, see “Vulcanization and Vulcanizing Agents” (W. Hoffman, Palmerton Publishing Company). Suitable phenolic curable resins and brominated phenolic curable resins are commercially available, for example such resins from Schenectady Chemicals, Inc. under the trade designations “SP-1045”, “CRJ-352”, “ It can be purchased as “SP-1055” and “SP-1056”. Similar functionally equivalent phenolic curable resins can also be obtained from other suppliers.

The phenol resin is a suitable vulcanizing agent from the viewpoint of preventing fogging because it hardly generates decomposition products.
The phenolic resin is used in an amount sufficient to achieve essentially complete vulcanization of the rubber.

The amount of the phenol resin used is usually the amount of the phenol curable resin with respect to 100 parts by weight of the total amount of the olefin resin (B), all rubber components, and ethylene / α-olefin copolymer (C). 0.5 to 10 parts by weight, preferably 0.5 to 5 parts by weight, more preferably 1 to 5 parts by weight.
The term “dynamically heat-treating” refers to kneading each component as described above in a molten state.

  As the kneading apparatus, a conventionally known kneading apparatus, for example, an open type mixing roll, a non-open type Banbury mixer, an extruder, a kneader, a continuous mixer or the like is used. Among these, a non-open type kneading apparatus is preferable, and the kneading is preferably performed in an atmosphere of an inert gas such as nitrogen gas or carbon dioxide gas.

The kneading is preferably performed at a temperature at which the half-life of the organic peroxide used is less than 1 minute. The kneading temperature is usually 150 to 280 ° C, preferably 170 to 240 ° C, and the kneading time is usually 1 to 20 minutes, preferably 1 to 10 minutes. The applied shear force is determined as a shear rate within a range of 10 to 50,000 sec ⁻¹ , preferably 100 to 20,000 sec ⁻¹ .

  Since the thermoplastic elastomer composition of the present invention is composed of an olefin resin (B), rubber, and ethylene / α-olefin copolymer (C), it is excellent in high temperature fluidity and extrusion moldability. Molding can be performed using a molding apparatus conventionally used in molding, transfer molding, injection molding, extrusion molding and the like.

[Automobile interior parts]
The molded article of the present invention is obtained by molding the thermoplastic elastomer composition of the present invention, and is optimal for use as an automobile interior part.

The automobile interior part of the present invention is usually produced according to the following conventional method.
(1) Supply to a plastic processing machine such as an extrusion molding machine with a T-die or a calendar molding machine and mold it into a desired shape such as a sheet.
(2) Molding into a desired shape by injection molding.

  A surface layer made of at least one compound selected from polyurethane, saturated polyester, acrylic ester resin, polyvinyl chloride and isocyanate resin can be provided on the skin layer of the automobile interior part of the present invention.

  As the saturated polyester used for forming such a surface layer, polyethylene terephthalate, polybutylene terephthalate, and derivatives thereof are used. As the acrylic ester resin, polymethyl (meth) acrylate, polyisobutyl (meth) acrylate, poly-2-ethylhexyl (meth) acrylate, or the like is used. Furthermore, as the isocyanate resin, polyhexamethylene diisocyanate, polyisophorone diisocyanate, or the like is used.

  Such a surface layer is preferably 300 μm or less. A primer layer can be interposed between the skin layer and such a surface layer.

  Furthermore, the automobile interior part of the present invention can constitute a laminate with a polyolefin foam or a laminate with a polyolefin resin. Examples of the polyolefin used here include olefin-based resins used in the production of the olefin-based thermoplastic elastomer composition. In particular, polyethylene, polypropylene and the like are preferable.

  In such a laminate, for example, an olefinic thermoplastic elastomer composition is extruded using an extruder with a T-die, and the extruded thermoplastic elastomer composition in a molten state is laminated with a polyolefin foam sheet. It is manufactured by passing through a pair of rolls in a state or by sequential injection molding of a polyolefin resin and an olefinic thermoplastic elastomer.

  The automobile interior part of the present invention is mainly used as a skin layer for door trims, instrumental panels, ceilings, handles, console boxes, seats and the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
In the following, each physical property was measured or evaluated by the following method.

[Ethylene content, B value]
The ethylene content of the ethylene / α-olefin copolymer was determined from the “ ¹³ C-NMR spectrum” measured as follows, “Polymer Analysis Handbook” (Asakura Shoten 2008 First Edition P184-211), G.C. J. et al. Ray (Macromolecules, 10, 773 (1977)), J. MoI. C. Randall (Macro-molecules, 15, 353 (1982)), K. et al. It was determined based on the report of Kimura (Polymer, 25, 4418 (1984)).

The B value of the ethylene / α-olefin random copolymer was calculated by the following formula.
B value = POE / (2PO · PE)
(Wherein PE and PO are the mole fraction of the ethylene component and the mole fraction of the α-olefin component, respectively, contained in the ethylene / α-olefin copolymer, and POE is the total dyad) (The ratio of the number of alternating ethylene / α-olefin chains to the number of chains.)
The PE, PO, and POE values were obtained from ¹³ C-NMR spectra measured as follows based on the above-mentioned known literature.

Measurement conditions for ¹³ C-NMR spectrum Using an ECP500 type nuclear magnetic resonance apparatus manufactured by JEOL Ltd., a mixed solvent of o-dichlorobenzene / heavy benzene (80/20% by volume), a sample concentration of 55 mg / 0. 6 mL, measurement temperature 120 ° C., observation nucleus ¹³ C (125 MHz), sequence single pulse proton decoupling, pulse width 4.7 μsec (45 ° pulse), repetition time 5.5 seconds, integration count Measured 10,000 times or more using 27.50 ppm as the standard value for chemical shift.

[Intrinsic viscosity [η] measured in decalin at 135 ° C.]
Intrinsic viscosity [η] [dl / g] was measured in decalin at 135 ° C. using a fully automatic intrinsic viscometer manufactured by Kouaisha.
[Kinematic viscosity at 100 ° C]
The kinematic viscosity at 100 ° C. was measured by the method described in JIS K2283.

[Molecular weight (Mw) and molecular weight distribution (Mw / Mn)]
(Method A): Measurement in ethylene / α-olefin / non-conjugated polyene copolymer (A) The molecular weight was determined by using a liquid chromatograph: Waters ALC / GPC150-C plus type (suggested refractometer detector integrated type), Two columns of GMH6-HT manufactured by Tosoh Corporation and two of GMH6-HTL were connected in series as columns, and o-dichlorobenzene was used as a mobile phase medium, and measurement was performed at 140 ° C. at a flow rate of 1.0 ml / min.
Mw / Mn value was calculated by analyzing the obtained chromatogram by a known method using a calibration curve using a standard polystyrene sample. The measurement time per sample was 60 minutes.

(Method B): Measurement in ethylene / α-olefin copolymer (C) The molecular weight distribution was measured as follows using Tosoh Corporation HLC-8320GPC. As a separation column, TSKgel SuperMultipore HZ-M (4) was used, the column temperature was 40 ° C., tetrahydrofuran (manufactured by Wako Pure Chemical Industries) was used as the mobile phase, the development rate was 0.35 ml / min, and the sample concentration was The amount of sample injection was 20 microliters, and a differential refractometer was used as a detector. As the standard polystyrene, one manufactured by Tosoh Corporation (PStQuick MP-M) was used. According to the procedure of general-purpose calibration, the weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated as polystyrene molecular weight, and the molecular weight distribution (Mw / Mn) was calculated from these values.

[Melting point / Glass transition temperature (Tg)]
(Method A): Measurement in ethylene / α-olefin / non-conjugated polyene copolymer (A) or olefin-based resin (B) Seiko Instruments X-DSC-7000 is used for an aluminum sample pan that can be easily sealed. About 5 mg of ethylene / α-olefin / non-conjugated polyene copolymer (A) or olefin resin (B) molded into a sheet using a hydraulic hot press molding machine set at 200 ° C. Placed in the DSC cell, the DSC cell was heated from room temperature (23 ° C.) to 200 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere, then held at 200 ° C. for 5 minutes, and then cooled at 10 ° C./min. The DSC cell was cooled to −100 ° C. (temperature lowering process). Subsequently, after hold | maintaining for 5 minutes at -100 degreeC, it heated up at 10 degree-C / min (temperature rising process).

(Method B): Measurement in ethylene / α-olefin copolymer (C) Using Seiko Instruments Inc. X-DSC-7000, about 8 mg of ethylene / α-olefin copolymer is placed on an aluminum sample pan that can be easily sealed. And placed in the DSC cell. The DSC cell was heated from room temperature (23 ° C.) to 150 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere, then held at 150 ° C. for 5 minutes, and then at 10 ° C./min. The temperature was lowered, and the DSC cell was cooled to −100 ° C. (temperature lowering process). Subsequently, after hold | maintaining for 5 minutes at -100 degreeC, it heated up at 10 degree-C / min (temperature rising process).

analysis method:
The temperature at which the enthalpy curve obtained in the temperature raising process showed a maximum value was defined as the melting point (Tm), and the total amount of endotherm accompanying melting was defined as the heat of fusion (ΔH). When no peak was observed or the value of heat of fusion (ΔH) was 1 J / g or less, it was considered that the melting point (Tm) was not observed. The intersection of tangents at the inflection point of the enthalpy curve obtained in the temperature raising process was defined as the glass transition temperature (Tg). The method of obtaining the melting point (Tm), the heat of fusion (ΔH), and the glass transition temperature (Tg) was performed based on JIS K7121.

[Shore A hardness]
In accordance with JIS K6253, two press sheets with a thickness of 2 mm were stacked and measured with a Shore A hardness meter.

[Tensile properties]
Using a 50-ton press, a sheet sample of 20 cm × 20 cm × 2 mm prepared from the pellets of the thermoplastic elastomer composition is used as a test sample, a JIS No. 3 dumbbell is used in accordance with JIS K6251, measurement temperature is 25 ° C., tensile A tensile test was performed under the condition of a speed of 500 mm / min, and the following tensile properties were measured.
M100: Stress at 100% elongation TB: Tensile strength EB: Tensile elongation at break

[Compression set (CS)]
A 2 mmt sheet prepared in the following example was laminated, and a compression set test was performed in accordance with JIS K6262.
The test conditions were 12 mm thick (six pieces of 2 mm thick) laminated sheets, 25% compression, compression at −20 ° C. and 100 ° C. for 24 hours, after strain removal (compression) It was measured after 30 minutes.

<Ethylene / α-olefin / non-conjugated polyene copolymer (A)>
[Production Example 1] (Production of ethylene / propylene / diene copolymer (a-1))
Using a reactor with a stirrer made of SUS with a volume of 300 L, the temperature was kept at 80 ° C., the liquid level was 100 L, hexane was 26.8 kg / h, ethylene (C2) was 3.9 kg / h, and propylene (C3) was 5.4 kg / h, 5-ethylidene-2-norbornene (ENB) at a rate of 1.1 kg / h and hydrogen at a rate of 44 NL / h as the main catalyst [N- (1,1-dimethylethyl)- 1,1-dimethyl-1-[(1,2,3,3A, 8A-η) -1,5,6,7-tetrahydro-2-methyl-S-indacene-1-yl] silane aminate (2 -) - κN] [(1,2,3,4 -η) -1,3- pentadiene] - titanium and 0.07 mmol / h, as co-catalysts _{(C 6 H 5) 3 CB} (C 6 F 5) ₄ 0.28 mmol / h, the organic aluminized As a product, TIBA was continuously supplied to the reactor at a rate of 1.8 mmol / h to obtain a polymerization solution of a terpolymer (a-1) of ethylene, propylene and 5-ethylidene-2-norbornene. .
The polymerization pressure was 2.1 MPa (gauge pressure).

The resulting polymerization solution was desolvated by flash drying to obtain an ethylene / propylene / diene copolymer (a-1). The obtained polymer exhibited the following physical properties. Ethylene-derived structural unit content 57 mol%, intrinsic viscosity [η] = 1.64 dl / g measured in decalin at 135 ° C., iodine value = 16, Mw / Mn = 2.4, Mooney viscosity [ML _{1 + 4} (100 ° C.)] = 45.

<Ethylene / propylene copolymer (C)>
[Production Example 2] (Production of ethylene / propylene copolymer (c-1))
Ethyl aluminum sesquichloride (Al (C ₂ H ₅ ) _1.5 · Cl ₁ , adjusted to 96 mmol / L with 1 L of dehydrated hexane in a continuous polymerization reactor with a stirring blade having a volume of 2 L sufficiently purged with nitrogen. ₅ ) a hexane solution of 500 ml / h continuously for 1 hour, and further a hexane solution of VO (OC ₂ H ₅ ) Cl ₂ adjusted to 16 mmol / L as a catalyst in an amount of 500 ml / h. Hexane was continuously fed in an amount of 500 ml / h. On the other hand, from the upper part of the polymerization vessel, the polymerization solution was continuously extracted so that the polymerization solution in the polymerization vessel was always 1 L. Next, ethylene gas was supplied in an amount of 27 L / h, propylene gas in an amount of 26 L / h, and hydrogen gas in an amount of 100 L / h using a bubbling tube. The copolymerization reaction was carried out at 35 ° C. by circulating a refrigerant through a jacket attached to the outside of the polymerization vessel.

  The polymer solution containing the ethylene / propylene copolymer obtained under the above conditions was washed 3 times with 100 ml of 0.2 mol / L hydrochloric acid, then 3 times with 100 ml of distilled water, dried over magnesium sulfate, and then the solvent was reduced in pressure. Distilled off. The resulting polymer was dried overnight at 130 ° C. under reduced pressure. The analysis results of the obtained ethylene / propylene copolymer are shown in Table 1.

[Production Example 3] (Production of ethylene / propylene copolymer (c-2))
By charging 910 mL of heptane and 45 g of propylene into a 2 L stainless steel autoclave sufficiently purged with nitrogen, raising the temperature in the system to 130 ° C., and then supplying hydrogen 2.24 MPa and ethylene 0.09 MPa The total pressure was 3 MPaG. Next, 0.4 mmol of triisobutylaluminum, [methylphenylmethylene (η ⁵ -cyclopentadienyl) (η ⁵ -2,7-di-t-butylfluorenyl)] zirconium dichloride 0.0006 mmol and N, N— Polymerization was initiated by injecting 0.006 mmol of dimethylanilinium tetrakis (pentafluorophenyl) borate with nitrogen and setting the stirring rotation speed to 400 rpm. Thereafter, by continuously supplying only ethylene, the total pressure was kept at 3 MPaG, and polymerization was carried out at 130 ° C. for 5 minutes. After the polymerization was stopped by adding a small amount of ethanol to the system, unreacted ethylene, propylene and hydrogen were purged. The obtained polymer solution was washed 3 times with 1000 mL of 0.2 mol / l hydrochloric acid and then 3 times with 1000 mL of distilled water, dried over magnesium sulfate, and then the solvent was distilled off under reduced pressure. The obtained polymer was dried overnight at 80 ° C. under reduced pressure, and further, using a 2-03 type thin film distillation apparatus manufactured by Shinko Pantech, the degree of vacuum was maintained at 400 Pa, a set temperature of 180 ° C., and a flow rate of 3.1 ml. Thin film distillation was performed at / min to obtain 22.2 g of an ethylene / propylene copolymer. Further, the ethylene / propylene copolymer was subjected to a hydrogenation operation.

<Hydrogenation operation>
Add 100 mL of hexane solution of 0.5 wt% Pd / alumina catalyst and 500 mL of 30 wt% hexane solution of ethylene / α-olefin copolymer to 1 L stainless steel autoclave, seal the autoclave, and perform nitrogen replacement. It was. Next, the temperature was raised to 140 ° C. with stirring, and the inside of the system was replaced with hydrogen. Then, the pressure was increased to 1.5 MPa with hydrogen, and a hydrogenation reaction was performed for 15 minutes.

[Production Example 4] (Production of ethylene / propylene copolymer (c-3))
Ethylaluminum sesquichloride (Al (C ₂ H ₅ ) _1.5 · Cl adjusted to 96 mmol / L by adding 1 liter of dehydrated and purified hexane to a continuous polymerization reactor with a stirring blade having a capacity of 2 liters sufficiently purged with nitrogen. _1.5 ) of hexane solution was continuously supplied in an amount of 500 ml / h for 1 hour, and further hexane solution of VO (OC ₂ H ₅ ) Cl ₂ adjusted to 16 mmol / l as a catalyst was added in an amount of 500 ml / h. Then, hexane was continuously supplied in an amount of 500 ml / h. On the other hand, from the upper part of the polymerization vessel, the polymerization solution was continuously extracted so that the polymerization solution in the polymerization vessel was always 1 liter. Next, ethylene gas was supplied in an amount of 35 L / h, propylene gas was supplied in an amount of 35 L / h, and hydrogen gas was supplied in an amount of 80 L / h using a bubbling tube. The copolymerization reaction was carried out at 35 ° C. by circulating a refrigerant through a jacket attached to the outside of the polymerization vessel.

  The polymerization solution containing the ethylene / propylene copolymer obtained under the above conditions was washed 3 times with 100 mL of 0.2 mol / l hydrochloric acid, then 3 times with 100 mL of distilled water, dried over magnesium sulfate, and then the solvent was reduced in pressure. Distilled off. The resulting polymer was dried overnight at 130 ° C. under reduced pressure.

[Production Example 5] (Production of ethylene / propylene copolymer (c-4))
Ethylaluminum sesquichloride (Al (C ₂ H ₅ ) _1.5 · Cl adjusted to 96 mmol / L by adding 1 liter of dehydrated and purified hexane to a continuous polymerization reactor with a stirring blade having a capacity of 2 liters sufficiently purged with nitrogen. _1.5 ) of hexane solution was continuously supplied in an amount of 500 ml / h for 1 hour, and further hexane solution of VO (OC ₂ H ₅ ) Cl ₂ adjusted to 16 mmol / l as a catalyst was added in an amount of 500 ml / h. Then, hexane was continuously supplied in an amount of 500 ml / h. On the other hand, from the upper part of the polymerization vessel, the polymerization solution was continuously extracted so that the polymerization solution in the polymerization vessel was always 1 liter. Next, ethylene gas was supplied in an amount of 36 L / h, propylene gas was supplied in an amount of 36 L / h, and hydrogen gas was supplied in an amount of 30 L / h using a bubbling tube. The copolymerization reaction was carried out at 35 ° C. by circulating a refrigerant through a jacket attached to the outside of the polymerization vessel.

  The polymerization solution containing the ethylene / propylene copolymer obtained under the above conditions was washed 3 times with 100 mL of 0.2 mol / l hydrochloric acid, then 3 times with 100 mL of distilled water, dried over magnesium sulfate, and then the solvent was reduced in pressure. Distilled off. The resulting polymer was dried overnight at 130 ° C. under reduced pressure.

[Production Example 6] (Production of ethylene / propylene copolymer (c-5))
Ethylaluminum sesquichloride (Al (C ₂ H ₅ ) _1.5 · Cl adjusted to 96 mmol / L by adding 1 liter of hexane dehydrated and purified to a continuous polymerization reactor with a stirring blade having a capacity of 2 liters sufficiently purged with nitrogen. _1.5 ) of hexane solution was continuously supplied in an amount of 500 ml / h for 1 hour, and further hexane solution of VO (OC ₂ H ₅ ) Cl ₂ adjusted to 16 mmol / l as a catalyst was added in an amount of 500 ml / h. Then, hexane was continuously supplied in an amount of 500 ml / h. On the other hand, from the upper part of the polymerization vessel, the polymerization solution was continuously extracted so that the polymerization solution in the polymerization vessel was always 1 liter. Next, ethylene gas was supplied in an amount of 47 L / h, propylene gas in an amount of 47 L / h, and hydrogen gas in an amount of 20 L / h using a bubbling tube. The copolymerization reaction was carried out at 35 ° C. by circulating a refrigerant through a jacket attached to the outside of the polymerization vessel.

  The polymerization solution containing the ethylene / propylene copolymer obtained under the above conditions was washed 3 times with 100 mL of 0.2 mol / l hydrochloric acid, then 3 times with 100 mL of distilled water, dried over magnesium sulfate, and then the solvent was reduced in pressure. Distilled off. The resulting polymer was dried overnight at 130 ° C. under reduced pressure.

[Production Example 7] (Production of ethylene / propylene copolymer (c-6))
A glass polymerization vessel having an internal volume of 1 L, which was sufficiently purged with nitrogen, was charged with 250 mL of heptane. The polymer was continuously fed into the polymerization vessel at a flow rate of h and stirred at a stirring speed of 600 rpm. Next, 0.2 mmol of triisobutylaluminum was charged into the polymerization vessel, and then 0.688 mmol of MMAO and [ethylene (η ⁵ -cyclopentadienyl) (η ⁵ -2,7-di-t-butylfluorenyl)] Polymerization was started by charging 0.00230 mmol of zirconium dichloride premixed in toluene for 15 minutes or more into a polymerization vessel. Thereafter, continuous supply of ethylene, propylene and hydrogen was continued, and polymerization was carried out at 50 ° C. for 15 minutes. After the polymerization was stopped by adding a small amount of isobutyl alcohol into the system, unreacted monomers were purged. The obtained polymer solution was washed 3 times with 100 mL of 0.2 mol / l hydrochloric acid and then 3 times with 100 mL of distilled water, dried over magnesium sulfate, and then the solvent was distilled off under reduced pressure. The obtained polymer was dried overnight under reduced pressure at 80 ° C. to obtain 1.43 g of an ethylene / propylene copolymer. Further, this ethylene / propylene copolymer was subjected to hydrogenation in the same manner as in Production Example 3.

[Production Example 8] (Production of ethylene / propylene copolymer (c-7))
In Production Example 2, the ethylene / propylene copolymer (c-7) shown in Table 1 was obtained by appropriately adjusting the supply amount of ethylene gas, the supply amount of propylene gas, and the supply amount of hydrogen gas.
Table 1 shows the analysis results of the obtained ethylene / propylene copolymers.

[Examples 1 to 3 and Comparative Examples 1 to 4 ]
45 g of the ethylene / propylene / diene copolymer (a-1) obtained in Production Example 1 and Diana process oil (PW-380, manufactured by Idemitsu Kosan Co., Ltd.) or ethylene 27 g of propylene copolymers (c-1) to (c-7) were kneaded for 3 minutes at a set temperature of 100 ° C. and a screw speed of 60 rpm using a lab plast mill (75C100, manufactured by Toyo Seiki Co., Ltd.). 57.6 g of the resulting compound (71 parts by weight of ethylene / propylene / diene copolymer (a-1), 43 parts by weight of softening agent) was mixed with homopropylene (PP-1: trade name: Prime Polypro ™ J105G (Prime 14.4 g (29 parts by weight) of a polymer), 0.28 g (0.5 parts by weight) of an organic peroxide (Perhexine 25B, manufactured by NOF Corporation) as a crosslinking agent, and divinylbenzene 0 as a crosslinking aid. .19 g (0.34 parts by weight) was added and melt-kneaded for 3 minutes at a set temperature of 200 ° C. and a screw rotation speed of 60 rpm using a lab plast mill (75C100, manufactured by Toyo Seiki Co., Ltd.). Then, press molding was performed under the conditions of preheating 190 ° C., 6 minutes, pressurization, 4 minutes, cooling 10 ° C., and 5 minutes to obtain a 2 mm thick sheet-like thermoplastic elastomer.
The physical properties of the obtained thermoplastic elastomer were evaluated. The results are shown in Table 2.

  From the results shown in Table 2, it can be seen that the thermoplastic elastomer composition of the present invention is excellent in the balance between mechanical properties and rubber elasticity (compression set).

Claims (6)

90 to 10 parts by weight of ethylene / α-olefin / nonconjugated polyene copolymer (A), homopolypropylene, random copolymer of propylene and α-olefin other than propylene, and α-olefin other than propylene and propylene 10 to 90 parts by weight of the olefin resin (B), which is one or more propylene polymers selected from block copolymers , and 100 parts by weight of the total amount of (A) and (B), the following: Thermoplastic elastomer composition obtained by dynamically heat-treating a mixture containing 3 to 100 parts by weight of ethylene / α-olefin copolymer (C) satisfying requirements (i) to (vi) in the presence of a crosslinking agent .
(I) It has a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms.
(Ii) The content of structural units derived from ethylene is 30 to 70 mol% (provided that the total of the content of structural units derived from ethylene and the content of structural units derived from α-olefins is 100 mol%) ).
(Iii) The intrinsic viscosity [η] measured in decalin at 135 ° C. is 0.01 to 0.50 dl / g.
(Iv) The kinematic viscosity at 100 ° C. is 10 to 5,000 mm ² / s , and the kinematic viscosity at 40 ° C. is 100 to 4,999 mm ² / s .
(V) The ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) determined by gel permeation chromatography (GPC) is 1.0 to 3.0.
(Vi) The glass transition temperature (Tg) determined by differential scanning calorimetry (DSC) is -90 to -65 ° C. ^{2. The} thermoplastic elastomer composition according to claim 1, wherein the ethylene / α-olefin copolymer (C) has a kinematic viscosity at 100 ° C. of 10 to 2,500 mm ² / s. The thermoplastic elastomer composition according to claim 1 or 2 , wherein the crosslinking agent is an organic peroxide. The thermoplastic elastomer composition according to claim 1 or 2 , wherein the crosslinking agent is a phenol resin. The molded object obtained by shape | molding the thermoplastic elastomer composition of any one of Claims 1-4 . The molded article according to claim 5 , which is an automobile interior part.