JP4314154B2 - Automotive interior skin - Google Patents

Description

 The present invention relates to an automobile interior skin member made of an olefinic thermoplastic elastomer composition.

  Conventionally, vinyl chloride resin has been widely used for interior members of automobiles. Vinyl chloride resin is excellent in moldability to parts and relatively inexpensive, so it is widely used for interior skin materials such as instrument panels, doors, and ceilings, handle materials, lever knobs, and various grips. . However, in recent years, it has been pointed out that vinyl chloride resin may cause harmful gases during incineration, and studies have been made to replace the above parts with materials other than vinyl chloride resin.

  Particularly in automobile interior parts, olefinic thermoplastic elastomers are most widely used as an alternative to vinyl chloride resin. Olefin-based thermoplastic elastomer material is lightweight, has excellent moldability and parts processability, is easy to recycle, and does not generate harmful gases during combustion, but has poor scratch resistance. It has a point to be improved.

For this reason, olefinic thermoplastic elastomers are rarely used as they are for parts that require scratch resistance, and those with improved surface scratch resistance, such as surface treatment, are used. It's real.
Japanese Patent Publication No. 3-070742

  In order to solve the problems associated with the prior art, an automobile interior skin member made of an olefinic thermoplastic elastomer having superior scratch resistance compared to conventional olefinic thermoplastic elastomers is proposed.

The automobile interior skin member of the present invention is
An olefin resin (a);
Olefin-based thermoplastic elastomer composition comprising (a) :( b) = 15-60: 85-40) as an essential component when the ethylene-based copolymer rubber (b) is in a weight ratio (a + b = 100 parts by weight) . (A) and
(C-1) a repeating unit derived from propylene;
(C-2) from at least one olefin selected from olefins having 2 to 20 carbon atoms other than propylene and, if necessary, (c-3) at least one polyene selected from conjugated polyenes and non-conjugated polyenes Consisting of repeating units led and
When the total amount of the unit (c-1) and the unit (c-2) is 100 mol%, the unit (c-1) is contained in an amount of 99 to 50 mol%, and the unit (c-2) In an amount of 1 to 50 mol%, and an amount of 0 to 30 mol% of the unit (c-3) with respect to 100 mol% of the total amount of the units (c-1) and (c-2) And a syndiotactic propylene copolymer (C) having a syndiotactic structure in an amount of 5 to 200 parts by weight per 100 parts by weight of the olefinic thermoplastic elastomer composition (A) . An automobile interior skin member, characterized in that the ethylene copolymer rubber (b) is crosslinked .

  In addition to the olefinic thermoplastic elastomer composition (A) and the syndiotactic propylene copolymer (C), a polypropylene resin (D) may be used as necessary. In that case, it is desirable that the polypropylene resin (D) has a substantially syndiotactic structure.

  The interior skin is preferably manufactured by vacuum molding, stamping molding, powder slush molding, or injection molding.

  Furthermore, the intrinsic viscosity measured in decalin at 135 ° C. in the state before the syndiotactic propylene copolymer (C) is crosslinked is in the range of 0.01 to 10 dl / g, and gel permeation chromatography It is preferable that the molecular weight distribution obtained by the above is 4 or less and the glass transition temperature is 30 ° C. or less.

The syndiotactic propylene copolymer (c)
(A) a transition metal complex represented by the following general formula (I) or (II):
(B) (B-1) a compound that reacts with the transition metal in (A) to form an ionic complex,
It is preferably obtained in the presence of at least one catalyst system comprising (B-2) an organoaluminum oxy compound and (B-3) at least one compound selected from an organoaluminum compound.

(In the formulas (I) and (II), M represents Ti, Zr, Hf, Rn, Nd, Sm or Ru, and Cp ¹ and Cp ² represent cyclopentadienyl group and indenyl group which are π-bonded to M. Represents a fluorenyl group or a derivative group thereof, X ¹ and X ² represent an anionic ligand or a neutral Lewis base ligand, and Y contains a nitrogen atom, an oxygen atom, a phosphorus atom or a sulfur atom. Z is a ligand, and Z represents a C, O, B, S, Ge, Si or Sn atom or a group containing these atoms.)
Further, the automobile interior skin member according to the present invention is preferably cross-linked with the ethylene copolymer rubber (b).

    Furthermore, in the automobile interior skin member according to the present invention, the syndiotactic propylene copolymer (C) may be crosslinked.

  The automobile interior skin member as described above is excellent in scratch resistance and wear resistance, and has good moldability, heat resistance, and flexibility.

Hereinafter, the automobile interior skin member according to the present invention will be described in detail.
The automobile interior skin member according to the present invention is composed of a composition comprising an olefinic thermoplastic elastomer composition (A), a syndiotactic propylene copolymer (C), and, if necessary, a polypropylene resin (D). It is said.

<Olefin resin (a)>
The olefin resin (a) used in the present invention is preferably composed of a crystalline high molecular weight solid product obtained by polymerizing one or more monoolefins by either a high pressure method or a low pressure method. . The crystallization degree of the olefin resin (a) used in the present invention is usually desirably 10% or more. The crystallinity can be measured by a known wide angle diffraction method using X-rays. Examples of such a resin include isotactic and syndiotactic monoolefin polymer resins. These representative resins are commercially available.

  Specific examples of suitable raw material olefins for the olefin resin (a) include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene and 2-methyl-1- Examples include propene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 5-methyl-1-hexene. These olefins may be used alone or in combination of two or more.

  The polymerization mode may be random type or block type, and any polymerization mode can be adopted as long as a resinous material is obtained. These olefinic resins may be used alone or in combination of two or more.

Among these olefin resins (a), propylene polymers, specifically, propylene homopolymers, propylene / ethylene block copolymers, propylene / ethylene or propylene / ethylene / butene random copolymers are particularly preferable.
The polymerization form may be either isotactic or syndiotactic, but isotactic is particularly excellent in heat resistance.
The olefin resin (a) used in the present invention has an MFR (ASTM D 1238-65T, 230 ° C.) of usually 0.01 to 100 g / 10 minutes, particularly 0.05 to 50 g / 10 minutes. preferable.
The olefin resin (a) has a role of improving the fluidity and heat resistance of the composition.

In the present invention, the olefin resin (a) is preferably 10 parts by weight or more and less than 80 parts by weight, more preferably 15 to 60 parts by weight with respect to 100 parts by weight of the total amount of the olefin resin and the crosslinked rubber. It is used in the ratio.
When the olefin resin (a) is used in the above proportion, a composition excellent in heat resistance, flexibility and rubber elasticity and excellent in molding can be obtained.

<Ethylene copolymer rubber (b)>
The ethylene copolymer rubber (b) used in the present invention is an amorphous random rubber comprising ethylene and an α-olefin having 3 to 20 carbon atoms, or an elastic copolymer rubber having low crystallinity, or ethylene. It is an amorphous or low-crystalline random elastic copolymer rubber comprising an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene. The degree of crystallinity of such a rubber determined by a known wide-angle X-ray diffraction method is usually less than 10%.

  The ethylene / α-olefin molar ratio of such an ethylene copolymer (b) is usually 55/45 to 85/15, and among these, those in the range of 60/40 to 83/17 are preferred.

In the present invention, the olefin resin (a) is the total amount 100 parts by weight of the olefin resin and crosslinked rubber, used in a proportion of 1 5 to 60 parts by weight.

  The Mooney viscosity [ML1 + 4 (100 ° C.)] of the ethylene copolymer rubber (b) used in the present invention is usually in the range of 50 to 300, preferably 100 to 200.

  Moreover, it is preferable that the iodine value of this ethylene-type copolymer rubber (b) is 3-30, and it is especially preferable that it exists in the range of 5-25. When the iodine value of the ethylene-based copolymer rubber (b) is in such a range, the composition (A) excellent in moldability and rubber elasticity can be obtained by being well-crosslinked.

  As the ethylene copolymer rubber (b) used in the present invention, a so-called oil-extended product containing a softening agent can be used. Further, without using an oil-extended product, a softening agent may be added later, or a softening agent may be blended using both oil-extended and post-addition. By using a softener, a composition having more flexibility and moldability can be obtained. As the softening agent that can be used for the oil-extended product, a softening agent that is usually used for rubber can be used.

Specifically, petroleum-based substances such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and petroleum jelly;
Coal tars such as coal tar and coal tar pitch;
Fatty oils such as castor oil, linseed oil, rapeseed oil, soybean oil, coconut oil;
Waxes such as tall oil, beeswax, carnauba wax, lanolin;
Fatty acids such as ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate or metal salts thereof;
Synthetic polymer materials such as petroleum resins, coumarone indene resins, atactic polypropylene;
Ester plasticizers such as dioctyl phthalate, dioctyl adipate, dioctyl sebacate;
Other examples include microcrystalline wax, sub (factis), liquid polybutadiene, modified liquid polybutadiene, and liquid thiocol.
Among these softeners, paraffinic process oils are particularly preferable, and high viscosity type paraffinic process oils having a low content of low molecular weight components that are volatile are particularly preferable. Here, the high viscosity type refers to one having a kinematic viscosity at 40 ° C. in the range of 100 to 1000 centistokes.

  In the present invention, the softener is used in a proportion of 150 parts by weight or less, preferably 2 to 100 parts by weight, more preferably 5 to 60 parts by weight, based on 100 parts by weight of the ethylene copolymer rubber (b). .

  The ethylene copolymer rubber (b), which may be oil-extended as necessary, has a total amount of 100 parts by weight of the olefin resin (a) and the ethylene copolymer rubber (b). It is used in a proportion of 40 to 85 parts by weight, preferably 60 to 80 parts by weight. When the ethylene copolymer rubber (b) is used in the above proportion, a composition excellent in heat resistance, flexibility and rubber elasticity and excellent in molding can be obtained.

  In the present invention, a rubber other than the ethylene copolymer rubber (b) can be used as necessary in addition to the ethylene copolymer rubber (b) within a range not impairing the object of the present invention. Examples of the rubber other than the ethylene copolymer rubber (b) include styrene / butadiene rubber and hydrogenated products thereof, styrene / isoprene rubber and hydrogenated products thereof, polybutadiene rubber, polyisoprene rubber, nitrile rubber, and butyl rubber. , Polybutylene rubber, natural rubber, silicon rubber and the like. When a rubber other than the ethylene copolymer rubber (b) is used, it is usually 100 parts by weight or less, preferably 50 parts by weight or less with respect to 100 parts by weight of the ethylene copolymer rubber (b).

<Other ingredients>
In addition to the olefin resin (a) and the ethylene copolymer rubber (b), an inorganic filler can be blended with the olefin thermoplastic elastomer (A) according to the present invention.

As the inorganic filler used in the present invention, specifically, calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, Examples include basic magnesium carbonate, molybdenum disulfide, graphite, glass fiber, glass sphere, shirasu balloon, basic magnesium sulfate whisker, calcium titanate whisker, and aluminum borate whisker.

  In the present invention, the inorganic filler is usually 100 parts by weight or less, preferably 2 to 30 parts by weight with respect to 100 parts by weight of the total amount of the olefin resin (a) and the ethylene copolymer rubber (b). Used in proportions. When the inorganic filler is used in such an amount, the resulting composition has good rubber elasticity and moldability.

  Furthermore, in the present invention, in the olefin-based thermoplastic elastomer (A), conventionally known heat stabilizer, anti-aging agent, weathering stabilizer, antistatic agent, crystal nucleating agent, higher fatty acid amide, metal soap, A lubricant such as wax and silicone oil can be added as long as the object of the present invention is not impaired.

  The olefinic thermoplastic elastomer composition (A) according to the present invention comprises the above-described olefinic resin (a) and ethylene copolymer rubber (b), and a softener and / or inorganic filler blended as necessary. After mixing with an agent, etc., it is obtained by dynamically heat-treating. Here, “dynamically heat-treating” means kneading in a molten state.

  Moreover, the crosslinked olefinic thermoplastic elastomer composition (A) can be obtained by performing dynamic heat treatment in the presence of a crosslinking agent. By using the crosslinked olefinic thermoplastic elastomer, the heat resistance of the interior skin according to the present invention is improved.

  The crosslinking agent used here is an organic peroxide, phenol resin, sulfur, hydrosilicone compound, amino resin, quinone or its derivative, amine compound, azo compound, epoxy compound, isocyanate, etc., thermosetting type The crosslinking agent generally used with rubber | gum is mentioned. Of these crosslinking agents, organic peroxides are particularly preferred.

Specific examples of the organic peroxide used in the present invention 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-butylperbenzoate Tert-butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butylcumyl peroxide, and the like.

  Among these, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di- in terms of reactivity, odor, and scorch stability Bifunctional organic peroxides such as (tert-butylperoxy) hexyne-3,1,3-bis (tert-butylperoxyisopropyl) benzene are particularly preferred. Of these, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane is most preferred.

  Such an organic peroxide is generally used in an amount of 0.02 to 3 parts by weight, preferably 0.05 to 1 part by weight, with respect to 100 parts by weight of the entire workpiece. If the amount of the organic peroxide is 0.02 parts by weight or more, the thermoplastic elastomer composition obtained is preferable because the degree of crosslinking is high, and the heat resistance, tensile properties, and rubber elasticity are sufficient. Moreover, it is preferable from the point of the moldability of the thermoplastic elastomer composition obtained that this compounding quantity is 3 weight part or less.

In the present invention, in the crosslinking treatment with the organic peroxide, sulfur, p-quinonedioxime, p, p'-dibenzoylquinonedioxime, N-methyl-N-4-dinitrosoaniline, nitrosobenzene, diphenyl Peroxy crosslinking aids such as guanidine, trimethylolpropane-N, N'-m-phenylenedimaleimide, or divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylol Polyfunctional methacrylate monomers such as propane trimethacrylate and allyl methacrylate, and 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. In particular, divinylbenzene is most preferred in the present invention. Divinylbenzene is easy to handle, has good compatibility with the crystalline polyolefin resin (a) and the ethylene copolymer rubber (b), which are the main components of the cross-linked product, and an organic peroxide. Therefore, a thermoplastic elastomer composition having a uniform crosslinking effect by heat treatment and a balance between fluidity and physical properties can be obtained.

  The amount of the compound such as the above-mentioned crosslinking aid or polyfunctional vinyl monomer is usually 5 parts by weight or less, preferably 0.3 to 3 parts by weight with respect to 100 parts by weight of the whole object to be treated. Used in

  In order to accelerate the decomposition of organic peroxides, tertiary amines such as triethylamine, tributylamine, 2,4,6-tri (dimethylamino) phenol, aluminum, cobalt, vanadium, copper, calcium, zirconium, Decomposition accelerators such as naphthenates such as manganese, magnesium, lead, and mercury may be used.

  The dynamic heat treatment in the present invention is preferably performed in a non-open type apparatus, and is preferably performed in an inert gas atmosphere such as nitrogen or carbon dioxide. The temperature of the heat treatment ranges from the melting point of the crystalline polyolefin resin (a) to 300 ° C, and is usually 150 to 290 ° C, preferably 170 ° C to 270 ° C. The kneading time is usually 1 to 20 minutes, preferably 1 to 10 minutes. The applied shearing force is in the range of 10 to 10,000 sec-1, preferably 100 to 50,000 sec-1, in terms of shear rate.

  As the kneading apparatus, a mixing roll, an intensive mixer (for example, a Banbury mixer, a kneader), a uniaxial or biaxial extruder can be used, and a non-open type apparatus is preferable, and among these, a biaxial extruder is particularly preferable.

  The olefinic thermoplastic elastomer (A) of the present invention is desirably statically heat-treated in hot air after the dynamic heat treatment as described above. The heat treatment is preferably performed at 80 to 130 ° C. for about 1 to 10 hours. By this heat treatment, residues of the crosslinking agent and the like can be removed, the odor of the obtained product can be reduced, or a product with good fogging properties can be obtained.

Syndiotactic propylene copolymer (C)
The syndiotactic propylene copolymer used in the present invention is:
(C-1) a repeating unit derived from propylene;
(C-2) a repeating unit derived from at least one olefin selected from olefins having 2 to 20 carbon atoms other than propylene;
As needed, (c-3) consists of a repeating unit derived from at least one polyene selected from conjugated polyenes and non-conjugated polyenes.

  The unit (c-2) is ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 3-methyl-1-butene. , 1-decene, 1-dodecene, 1-tetradodecene, 1-hexadecene, 1-octadecene, 1-eicocene and other linear or branched α-olefins; cyclopentene, cycloheptene, norbornene, 5-ethyl-2-norbornene Carbon atoms excluding propylene such as cycloolefin, tetracyclododecene, 2-ethyl-1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a-octahydronaphthalene It is a repeating unit derived from at least one olefin selected from olefins of 2 to 20.

  In the present invention, the unit (c-2) is a repeating unit derived from at least one olefin selected from ethylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene and 1-decene. It is preferable that it is a repeating unit derived from ethylene or butene. (C-2) Two or more types of units may be contained.

  The (c-3) unit is a repeating unit derived from at least one polyene selected from the following conjugated polyenes and non-conjugated polyenes.

  Specific examples of the conjugated polyene include 1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1-phenyl-1,3-butadiene, 1- Phenyl-2,4-pentadiene, isoprene, 2-ethyl-1,3-butadiene, 2-propyl-1,3-butadiene, 2-butyl-1,3-butadiene, 2-pentyl-1,3-butadiene, Conjugated dienes such as 2-hexyl-1,3-butadiene, 2-heptyl-1,3-butadiene, 2-octyl-1,3-butadiene, 2-phenyl-1,3-butadiene; 1,3,5- Examples thereof include conjugated trienes such as hexatriene. Of these, butadiene, isoprene, pentadiene, hexadiene, and octadiene are preferable, and butadiene and isoprene are particularly preferable in terms of excellent copolymerizability.

Specific examples of non-conjugated polyenes include dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4- Ethyl-1,4-hexadiene, 5-methyl-1,4-heptadiene, 5-ethyl-1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 5- Ethyl-1,5-heptadiene, 4-methyl-1,4-octadiene, 5-methyl-1,4-octadiene, 4-ethyl-1,4-octadiene, 5-ethyl-1,4-octadiene, 5- Methyl-1,5-octadiene, 6-methyl-1,5-octadiene, 5-ethyl-1,5-octadiene, 6-ethyl-1,5-octadiene, 6-methyl-1,6-octadiene, 7- Methyl-1,6-octadiene, 6-ethyl-1,6-octadiene, 4-methyl-1,4-nonadiene, 5-methyl-1,4-nonadiene, 4-ethyl-1,4-nonadiene , 5-ethyl-1,4-nonadiene, 5-methyl-1,5-nonadiene, 6-methyl-1,5-nonadiene, 5-ethyl-1,5-nonadiene, 6-ethyl-1,5- Nonadiene, 6-methyl-1,6-nonadiene, 7-methyl-1,6-nonadiene, 6-ethyl-1,6-nonadiene, 7-ethyl-1,6-nonadiene, 7-methyl-1,7- Nonadiene, 8-methyl-1,7-nonadiene, 7-ethyl-1,7-nonadiene, 5-methyl-1,4-decadiene, 5-ethyl-1,4-decadiene, 5-methyl-1,5- Decadiene, 6-methyl-1,5-decadiene, 5-ethyl-1,5-decadiene, 6-ethyl-1,5-decadiene, 6-methyl-1,6-decadiene, 7-methyl-1,6- Decadiene, 6-ethyl-1,6-decadiene, 7-ethyl-1,6-decadiene, 7-methyl-1,7-decadiene, 8-methyl-1,7-decadiene, 7-ethyl-1,7- Decadiene, 8-ethyl-1,7-decadiene, 8-methyl-1,8-decadiene, 9-methyl-1,8-decadiene, 8-ethyl-1,8-decadiene, 9-me Non-conjugated dienes such as Le 1,8 undecadiene;
6,10-dimethyl-1,5,9-undecatriene, 4,8-dimethyl-1,4,8-decatriene, 5,9-dimethyl-1,4,8-decatriene, 6,9-dimethyl- 1,5,8-decatriene, 6,8,9-trimethyl-1,5,8-decatriene, 6-ethyl-10-methyl-1,5,9-undecatriene, 4-ethylidene-1,6- Octadiene, 7-methyl-4-ethylidene-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene, 7-methyl-4-ethylidene-1,6-nonadiene, 7-ethyl-4- Ethylidene-1,6-nonadiene, 6,7-dimethyl-4-ethylidene-1,6-octadiene, 6,7-dimethyl-4-ethylidene-1,6-nonadiene, 4-ethylidene-1,6-decadiene, 7-methyl-4-ethylidene-1,6-decadiene, 7-methyl-6-propyl-4-ethylidene-1,6-octadiene, 4-ethylidene-1,7-nonadiene, 8-methyl-4-ethylidene- Non-conjugated trienes such as 1,7-nonadiene and 4-ethylidene-1,7-undecadiene It is below.

  Such non-conjugated polyene is preferable in that it has excellent wear resistance when crosslinked.

  Among these, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, dicyclopentadiene (DCPD), 4,8-dimethyl-1,4,8-decatriene (DMDT), 4-ethylidene-8- Methyl-1,7-nonadiene (EMND) is preferred. (C-3) Two or more types of units may be contained.

  The syndiotactic propylene copolymer is usually in an amount of 99 to 50 mol% of the unit (c-1) when the total amount of the (c-1) unit and the (c-2) unit is 100 mol%, preferably Is contained in an amount of 98 to 60 mol%, particularly preferably 90 to 65 mol%, and the unit (c-2) is usually 1 to 50 mol%, preferably 1 to 40 mol%, more preferably Is contained in an amount of 5 to 35 mol%.

  The syndiotactic propylene copolymer containing the (c-1) unit and the (c-2) unit in such an amount has good compatibility with the thermoplastic resin, and is excellent in scratch resistance and wear resistance. .

The syndiotactic propylene copolymer is usually 0.01 to 30 mol% of the (c-3) unit with respect to 100 mol% of the total amount of the (c-1) unit and (c-2) unit. May be included, preferably in an amount of 0.1 to 30 mol%, more preferably in an amount of 0.3 to 20 mol%.
When the syndiotactic propylene copolymer is cross-linked, by including the unit (c-3), the cross-linking efficiency is increased and the heat resistance is improved.

  As the syndiotactic propylene copolymer used in the present invention, those having a crystallinity of less than 10% determined by wide-angle X-ray diffraction are usually used.

  The syndiotactic propylene copolymer used in the present invention has a substantially syndiotactic structure, the syndiotactic parameter is 0.6 or more, preferably 0.7 or more, and the syndiotacticity is Within such a range, the crystallization speed is high and the processability is excellent. In the present specification, the phrase “substantially syndiotactic structure” means that the syndiotacticity parameter is 0.6 or more.

Here, the syndiotacticity parameter will be described.
The syndiotacticity parameter (hereinafter sometimes referred to as “SP value”) of this syndiotactic propylene copolymer is determined by the ¹³ C-NMR spectrum of the syndiotactic propylene copolymer and the following formula (1). -It is calculated | required as intensity | strength (area) ratio of the side chain methyl group of the 2nd unit of the propylene unit 3 chain | linkage part which carried out tail coupling | bonding. That is, it is obtained as described in paragraphs 0025 to 0036 of JP-A-2002-097284.

SP value = signal area of the third region (19.5-20.3 ppm) / {signal area of the first region (21.0-21.9 ppm) + signal area of the second region (20.3-21.0 ppm) + third region (19.5-20.3) ppm) signal area} (1)
The first region is indicated by PPP (mm), the second region is indicated by PPP (mr), and the third region is indicated by PPP (rr), which respectively represent a head-to-tail linked propylene triunit chain having the following structure.

  In addition, in the methyl carbon region (19 to 23 ppm), in addition to the side chain methyl group of the propylene unit in the head-to-tail coupled propylene 3 chain as described above, the side chain of the propylene unit in the other chain as described below. A methyl group peak is observed. When determining the SP value, the peak area of the methyl group that is not based on such a three-chain structure of propylene units is corrected as follows. P represents a repeating unit derived from propylene, and E represents a repeating unit derived from ethylene.

  1) In the second region, a peak derived from the side chain methyl group of the second unit (propylene unit) in the PPE3 chain in which propylene is head-to-tail bonded is observed.

  The area of this methyl group peak can be determined from the peak area of the methine group (resonance at around 30.6 ppm) of the second unit (propylene unit) in the PPE chain.

  2) In the third region, a peak derived from the side chain methyl group of the second unit (propylene unit) in the EPE3 chain is observed.

  This methyl group peak area can be determined from the peak area of the methine group (resonance at around 32.9 ppm) of the second unit (propylene unit) in the EPE chain.

  3) In the second region and the third region, in the position irregular unit as shown by the following partial structures (i), (ii) and (iii) contained in a small amount in the ethylene / ethylene random copolymer: Peaks derived from the methyl groups C to E ′ are observed.

In the second region, a methyl group C peak, a methyl group D peak and a methyl group D ′ peak are observed,
In the third region, a methyl group E peak and a methyl group E ′ peak are observed.

  In the methyl groups in the position irregular units (i) to (iii), the methyl group A peak and the methyl group B peak are observed at 17.3 ppm and 17.0 ppm, respectively, and are not observed in the first to third regions. .

The peak area of the methyl group C can be determined from the peak area of the adjacent methine group (resonance near 31.3 ppm).
The peak area of the methyl group D can be obtained from ½ of the sum of the peak areas of the peaks (around 34.3 ppm and around 34.5 ppm) based on the αβ methylene carbon of the structure (ii).
The peak area of the methyl group D ′ can be determined from the area of the peak (around 33.3 ppm) based on the methine group adjacent to the methyl group E ′ of the structure (iii).
The peak area of the methyl group E can be determined from the peak area of the adjacent methine carbon (near 33.7 ppm).
The peak area of the methyl group E ′ can be determined from the peak area of the adjacent methine carbon (near 33.3 ppm).
Therefore, by subtracting these peak areas from the total peak areas of the second region and the third region, the peak area of the side chain methyl group of the second propylene unit in the three head-to-tail bonded propylene units can be determined. .
Each carbon peak in the spectrum can be assigned with reference to literature (Polymer, 30, 1350 (1989)).

In addition, this syndiotactic structure is specifically measured as follows.
That is, 0.35 g of a sample is dissolved by heating in 2.0 ml of hexachlorobutadiene. After this solution is filtered through a glass filter (G2), 0.5 ml of deuterated benzene is added and charged into an NMR tube having an inner diameter of 10 mm. And ¹³ C-NMR measurement is performed at 120 degreeC using the JEOL GX-500 type | mold NMR measuring apparatus. The number of integration is 10,000 times or more.

  In a preferred embodiment of the present invention, the unit (c-2) is an ethylene unit, and the content of the ethylene unit is 100 mol% in the total amount of the unit (c-1) and the unit (c-2). Sometimes it is in the range of 1 to 40 mol% and the SP value is 0.6 or more, preferably 0.7 or more.

  Such a syndiotactic propylene copolymer has an intrinsic viscosity [η] measured in decalin at 135 ° C. of usually 0.01 to 10 dl / g, preferably 0.05 to 10 dl / g. desirable. When the intrinsic viscosity [η] of the syndiotactic propylene copolymer is within the above range, the syndiotactic propylene copolymer is excellent in properties such as scratch resistance, abrasion resistance, and moldability.

  The syndiotactic propylene copolymer preferably has an iodine value of usually 0 to 50, preferably 1 to 40, and more preferably 3 to 30.

  Further, the syndiotactic propylene copolymer has a single glass transition temperature, and the glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) is usually 30 ° C. or lower, preferably 20 ° C. or lower. It is desirable to be in range. A syndiotactic propylene copolymer in which the glass transition temperature (Tg) of the syndiotactic propylene copolymer is within the above range is excellent in rubber elasticity and vibration damping, cold resistance, and low temperature characteristics.

  The syndiotactic propylene copolymer preferably has a temperature (Tm) at the maximum peak position in the endothermic curve of DSC of less than 110 ° C., preferably no Tm.

  Tm is measured by filling a sample in an aluminum pan, heating up to 200 ° C. at 100 ° C./min, holding at 200 ° C. for 5 minutes, then lowering to −150 ° C. at 10 ° C./min, then 10 ° C./min. Obtained from the endothermic curve when the temperature is raised at

  The syndiotactic propylene copolymer has a molecular weight distribution (Mw / Mn, converted to polystyrene, Mw: weight average molecular weight, Mn: number average molecular weight) measured by gel permeation chromatography (GPC) of 4.0 or less. Is preferred.

Method for Producing Syndiotactic Propylene Copolymer In producing such a syndiotactic propylene copolymer, a metallocene catalyst as described later is preferably used as the catalyst.

  In the production of the syndiotactic propylene copolymer, JP-A-2-41303, JP-A-41305, JP-A-2-274703, JP-A-2-274704 are used in place of the catalyst system. It is also possible to use a catalyst system described in JP-A-3-179900, JP-A-3-179006, JP-A-4-69394, JP-A-5-17589, or JP-A-8-120127. it can.

  Specifically, the catalyst system described in JEwen et al., “J. Am. Chem. Soc., 1988, 110, 6255-6256” described in the above “Technical Background of the Invention” may be used. The syndiotactic triad fraction of the resulting polymer (A. Zambelli et al. Macromolecules vol 6 687 (1973); vol 8 925 (1975)) can be used as long as it is a catalyst system that gives a polymer having a relatively high tacticity of, for example, about 0.5 or more. Examples thereof include a catalyst system comprising a bridged transition metal compound having asymmetric ligands and a promoter such as organoaluminum.

  Examples of the bridged transition metal compound having asymmetric ligands constituting such a catalyst system include diphenylmethylene (cyclopentadienyl) (fluorenyl) hafnium dichloride and diphenylmethylene (cyclopenta) described in the above-mentioned literature. Dienyl) (fluorenyl) zirconium dichloride, isopropyl (cyclopentadienyl-1-fluorenyl) hafnium dichloride, isopropyl (cyclopentadienyl-1-fluorenyl) zirconium dichloride, (t-butylamido) dimethyl (fluorenyl) silane titanium dimethyl, And diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride.

  The syndiotactic propylene copolymer used in the present invention is, for example, conjugated with propylene, at least one olefin selected from olefins having 2 to 20 carbon atoms excluding propylene, in the presence of the catalyst as described above. It can be produced by polymerizing at least one polyene selected from polyenes and non-conjugated polyenes so as to finally have the above-mentioned properties.

  The polymerization can be carried out by either a liquid phase polymerization method such as suspension polymerization or solution polymerization, or a gas phase polymerization method.

  In the liquid phase polymerization method, as a polymerization medium, aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane and kerosene; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclopentane; benzene Inert hydrocarbon solvents such as aromatic hydrocarbons such as toluene, xylene; halogenated hydrocarbons such as ethylene chloride, chlorobenzene, dichloromethane, or mixtures thereof, and propylene can also be used as the solvent .

  The polymerization is desirably performed at a temperature of usually −50 to 100 ° C., preferably 0 to 90 ° C. when the suspension polymerization method is performed, and is usually 0 to 250 when the solution polymerization method is performed. It is desirable to carry out at a temperature of ° C, preferably 20 to 200 ° C. Moreover, when implementing a gas phase polymerization method, it is desirable that superposition | polymerization is normally performed at the temperature of 0-120 degreeC, Preferably it is 20-100 degreeC. The polymerization is usually carried out under normal pressure to 10 MPa, preferably normal pressure to 5 MPa.

  The polymerization can be carried out in any of batch, semi-continuous and continuous methods. Furthermore, the polymerization can be performed in two or more stages having different reaction conditions.

  The molecular weight of the resulting syndiotactic propylene copolymer can be adjusted by allowing hydrogen to be present in the polymerization system or changing the polymerization temperature and the polymerization pressure.

More specifically, the syndiotactic propylene copolymer used in the present invention is, for example, (A) a transition metal complex represented by the following general formula (I) or (II):
(B) (B-1) A compound that reacts with the transition metal M in (A) to form an ionic complex (hereinafter sometimes referred to as “ionized ionic compound”).
In the presence of at least one catalyst system comprising (B-2) an organoaluminum oxy compound, and (B-3) at least one compound selected from organoaluminum compounds, the number of carbon atoms excluding propylene and 2 excluding propylene It is obtained by copolymerizing at least one olefin selected from -20 olefins and at least one polyene selected from conjugated polyenes and non-conjugated polyenes.

(A) Transition metal complex The transition metal complex forming the metallocene catalyst is represented by the following general formula (I) or (II).

  In the formulas (I) and (II), M represents Ti, Zr, Hf, Rn, Nd, Sm or Ru, and preferably Ti, Zr or Hf.

Cp ¹ and Cp ² may be the same or different from each other, and are a cyclopentadienyl group, an indenyl group, a fluorenyl group, or a derivative group thereof π-bonded to M. More specifically, Cp ¹ and Cp ² are ligands coordinated to the transition metal M, and cyclopentadienyl group, indenyl group, 4,5,6,7-tetrahydroindenyl group, fluorenyl group, and the like. This is a ligand having a pentadienyl skeleton, and the ligand having a cyclopentadienyl skeleton may have a substituent such as an alkyl group, a cycloalkyl group, a trialkylsilyl group, or a halogen atom. .

X ¹ and X ² may be the same as or different from each other, and are an anionic ligand or a neutral Lewis base ligand. Specifically, a hydrocarbon group having 1 to 12 carbon atoms, an alkoxy group, an aryloxy group, a sulfonic acid-containing group (—SO ₃ R ^a , where R ^a is an alkyl group, an alkyl group substituted with a halogen atom, An aryl group, an aryl group substituted with a halogen atom, or an aryl group substituted with an alkyl group.), A halogen atom, a hydrogen atom, and the like.

  Y is a ligand containing a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom, and Z and Y may form a condensed ring.

Z represents a C, O, B, S, Ge, Si or Sn atom or a group containing these atoms. These atoms may have a substituent such as an alkyl group or an alkoxy group, and the substituents of Z may be bonded to each other to form a ring. Examples of the bonding group Z include a divalent hydrocarbon group having 1 to 20 carbon atoms, a divalent halogenated hydrocarbon group having 1 to 20 carbon atoms, a divalent silicon-containing group, and a divalent germanium-containing group. Divalent tin-containing group, —CO—, —SO—, —SO ₂ —, —BR ^b — (where R ^b is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, the number of carbon atoms 1-20 halogenated hydrocarbon groups) and the like, and preferably a group containing one O, Si or C.

  Below, an example of the transition metal complex represented by the said general formula (I) or (II) is shown.

  Diphenylmethylene (cyclopentadienyl) (fluorenyl) hafnium dichloride, diphenylmethylene (cyclopentadienyl) fluorenylzirconium dichloride, isopropyl (cyclopentadienyl-1-fluorenyl) hafnium dichloride, isopropyl (cyclopentadienyl-1 -Fluorenyl) zirconium dichloride, (t-butylamido) dimethyl (fluorenyl) silane titanium dimethyl, diphenylmethylene (cyclopentadienyl) fluorenylzirconium dichloride and the like.

  In addition, a transition metal complex in which zirconium metal is replaced with titanium metal or hafnium metal in the compound as described above can be exemplified, and a transition metal complex in which hafnium metal is replaced with zirconium metal or titanium metal can also be exemplified. it can.

  The transition metal complexes as described above can be used alone or in combination of two or more.

The particulate carrier or the transition metal complex (A) as described above can be used by being supported on the particulate carrier.

Examples of such particulate carriers include inorganic carriers such as SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , MgO, ZrO ₂ , CaO, TiO ₂ , ZnO, SnO ₂ , BaO, and ThO; poly α-olefins Organic carriers such as polypropylene, poly-1-butene, poly-4-methyl-1-pentene, and styrene-divinylbenzene copolymer can be used. These particulate carriers can be used alone or in combination of two or more.

(B-1) Ionized ionic compound An ionized ionic compound is a compound that reacts with the transition metal M in the transition metal complex (A) to form an ionic complex, and as such an ionized ionic compound, And Lewis acids, ionic compounds, borane compounds and carborane compounds.

The Lewis acid, BR ₃ (wherein, R represents a fluorine atom, a methyl group, a phenyl group or a fluorine atom may have a substituent such as a trifluoromethyl group.
), For example, trifluoroboron, triphenylboron, tris (4-fluorophenyl) boron, tris (3,5-difluorophenyl) boron, tris (4-fluoromethylphenyl) boron, tris ( Pentafluorophenyl) boron, tris (p-tolyl) boron, tris (o-tolyl) boron, tris (3,5-dimethylphenyl) boron and the like.

  Examples of the ionic compound include trialkyl-substituted ammonium salts, N, N-dialkylanilinium salts, dialkylammonium salts, and triarylphosphonium salts. Specifically, examples of the trialkyl-substituted ammonium salt include triethylammonium tetra (phenyl) boron, tripropylammonium tetra (phenyl) boron, and tri (n-butyl) ammonium tetra (phenyl) boron. Examples of the dialkylammonium salt include di (1-propyl) ammonium tetra (pentafluorophenyl) boron and dicyclohexylammonium tetra (phenyl) boron. Furthermore, examples of the ionic compound include triphenylcarbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, ferrocenium tetra (pentafluorophenyl) borate and the like.

  Examples of borane compounds include decaborane (14), bis [tri (n-butyl) ammonium] nonaborate, bis [tri (n-butyl) ammonium] decaborate, bis [tri (n-butyl) ammonium] bis (dodecahydridododecaborate ) Metal borane anion salts such as nickelate (III).

  Examples of the carborane compounds include 4-carbanonaborane (14), 1,3-dicarbanonaborane (13), bis [tri (n-butyl) ammonium] bis (undecahydride-7-carbaundecaborate) nickelate And salts of metal carborane anions such as (IV).

  The ionized ionic compounds as described above can be used alone or in combination of two or more.

(B-2) Organoaluminum Oxy Compound The organoaluminum oxy compound (B-2) may be a conventionally known aluminoxane, or a benzene insoluble organoaluminum as exemplified in JP-A-2-78687. It may be an oxy compound.

  The conventionally known aluminoxane (alumoxane) is specifically represented by the following general formula.

  In the formula, R is a hydrocarbon group such as a methyl group, an ethyl group, a propyl group, or a butyl group, preferably a methyl group, an ethyl group, and particularly preferably a methyl group.

  m is an integer greater than or equal to 2, Preferably it is an integer of 5-40.

Here, the aluminoxane is an alkyloxyaluminum unit represented by the formula (OAl (R ¹ )) and an alkyloxyaluminum unit represented by the formula (OAl (R ² )) (where R ¹ and R ² are R and The same hydrocarbon group, and R ¹ and R ² represent different groups.

The organoaluminum oxy compound may contain a small amount of a metal organic compound component other than aluminum.
The organoaluminum oxy compounds as described above can be used singly or in combination of two or more.
The organoaluminum oxy compound or ionized ionic compound can also be used by being supported on the particulate carrier described above.
In forming the catalyst, the following organoaluminum compound (B-3) may be used together with the ionized ionic compound (B-1) or the organoaluminum oxy compound (B-2).

(B-3) Organoaluminum compound As the organoaluminum compound, a compound having at least one Al-carbon bond in the molecule can be used. Examples of such a compound include organoaluminum compounds represented by the following general formula.

(R ¹ ) _m Al (O (R ² )) _n H _p X _q
(In the formula, R ¹ and R ² may be the same or different from each other, and each represents a hydrocarbon group having usually 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X represents a halogen atom, and m represents 0. <M ≦ 3, n is 0 ≦ n <3, p is 0 ≦ p <3, q is a number satisfying 0 ≦ q <3, and m + n + p + q = 3)
In the present invention, as the catalyst for producing the syndiotactic propylene copolymer, a metallocene catalyst as described above is preferably used. However, in some cases, a conventionally known solid titanium other than the metallocene catalyst is used. A titanium-based catalyst composed of a catalyst component and an organoaluminum compound, and a vanadium-based catalyst composed of a soluble vanadium compound and an organoaluminum compound can also be used.

  In the present invention, propylene, an olefin other than propylene, and a polyene are usually copolymerized in the liquid phase in the presence of the metallocene catalyst as described above. At this time, an inert hydrocarbon solvent as described above is generally used, but propylene may be used as a solvent. Copolymerization can be carried out by either a batch method or a continuous method.

When a metallocene catalyst is used and the copolymerization is carried out by a batch method, the concentration of the transition metal complex (A) in the polymerization system is usually from 0.00005 to 1 mmol, preferably from 0.005 to 1 liter per polymerization volume. Used in an amount of 0001 to 0.5 mmol.
The ionized ionic compound (B-1) is an amount such that the molar ratio (B-1 / A) of the ionized ionic compound to the transition metal complex (A) is 0.5 to 20, preferably 1 to 10. Used in
The organoaluminum oxy compound (B-2) has a molar ratio (Al / M) of aluminum atoms (Al) to transition metal atoms (M) in the transition metal complex (A) of 1 to 10000, preferably 10 to 5000. Is used in such an amount that
When an organoaluminum compound is used, it is usually used in an amount of about 0 to 5 mmol, preferably about 0 to 2 mmol per liter of polymerization volume.
The copolymerization reaction is usually performed at a temperature in the range of −20 to 150 ° C., preferably 0 to 120 ° C., more preferably 0 to 100 ° C., and a pressure exceeding 0 to 8 MPa, preferably exceeding 0 to 5 MPa. Performed under conditions in the range of.
The reaction time (average residence time when copolymerization is carried out in a continuous process) varies depending on conditions such as catalyst concentration and polymerization temperature, but is usually 5 minutes to 3 hours, preferably 10 minutes to 1.5. It's time.

  When propylene, olefin and polyene are copolymerized as described above, a syndiotactic propylene copolymer is usually obtained as a polymerization liquid containing the same. This polymerization liquid is processed by a conventional method to obtain a syndiotactic propylene copolymer (C).

  In the present invention, the syndiotactic propylene copolymer (C) is 5 to 200 parts by weight, preferably 10 to 100 parts by weight, more preferably 100 parts by weight of the olefinic thermoplastic elastomer composition (A). It is used in a proportion of 20 to 70 parts by weight.

  By using it in the above ratio, an automobile skin member having excellent scratch resistance and wear resistance, and excellent heat resistance, moldability, and flexibility can be obtained.

Polypropylene (D)
As the polypropylene resin (D) used as necessary in the present invention, any of a commercially available homotype, block type, and random type can be used, and any of isotactic and syndiotactic can be used. . Among these, syndiotactic polypropylene resin is particularly preferable from the viewpoint of scratch resistance and abrasion resistance. In that case, the syndiotacticity parameter mentioned above is 0.6 or more, preferably 0.7 or more. The syndiotactic polypropylene resin can be produced by a known method using the same catalyst as the above-mentioned (C).

The melt flow rate (230 ° C., 2.16 kg load) of the polypropylene resin (d) is more preferably 0.01 to 100 g / 10 minutes.
As the polypropylene resin (D) according to the present invention, those having a crystallinity of 10% or more usually obtained by wide-angle X-ray diffraction are used.
The polypropylene resin (D) according to the present invention is used in a proportion of 0 to 200 parts by weight, preferably 20 to 100 parts by weight, based on 100 parts by weight of the syndiotactic propylene copolymer (C).

<Other ingredients>
In addition to the syndiotactic propylene copolymer (C) and the polypropylene resin (D), the automotive interior skin member according to the present invention has the same softening agent and / or inorganic filling as the olefin thermoplastic elastomer (A). Agents can be blended. Further, conventionally known heat stabilizers, anti-aging agents, weathering stabilizers, antistatic agents, metal soaps, waxes, silicone oils, lubricants such as higher fatty acid amides, etc. should be added within a range that does not impair the purpose of the present invention. Can do.

The composition for automotive interior skin members according to the present invention is blended as necessary with the above-described olefinic thermoplastic elastomer (A), syndiotactic propylene copolymer (C) and polypropylene resin (D). After mixing with a softener and / or an inorganic filler, etc., it is obtained by dynamically heat-treating. Here, “dynamically heat-treating” means kneading in a molten state.
Furthermore, a composition in which the syndiotactic propylene copolymer (C) is crosslinked can be obtained by performing dynamic heat treatment in the presence of a crosslinking agent. By cross-linking, heat resistance is improved.
For crosslinking of the olefinic thermoplastic elastomer (B), a crosslinking agent, a crosslinking aid, and a decomposition accelerator used in the olefinic thermoplastic elastomer (A) can be used.
In addition, the dynamic heat treatment at this time can be performed by the same method as that for the olefin-based thermoplastic elastomer (A).

  Moreover, when adopting a method of irradiating an electron beam as a crosslinking method, after obtaining a uniform composition by the above-mentioned dynamic heat treatment, an extrusion molding machine, an injection molding machine, a hollow molding machine, a calendar roll or a press, etc. By forming into an intended shape and irradiating with an electron beam, a crosslinked product is obtained. The electron beam irradiation is performed using an electron beam having an energy of 0.1 to 10 MeV (megaelectron volts), preferably 0.3 to 2 MeV, and an absorbed dose of 0.5 to 35 Mrad (megarad), preferably 0.5 to It is desirable to carry out so that it may become 10 Mrad.

  The composition according to the present invention is excellent in scratch resistance and abrasion resistance, and has good moldability, heat resistance and flexibility.

Interior skin Specifically as an automobile interior skin member which concerns on this invention, the following are mentioned.
i) Instrument panel (instrument panel) skin, door skin processed by vacuum molding or stamping molding of a sheet-like molded body obtained by extrusion molding or calendar molding of the composition of the present invention, Ceiling skin, console skin, etc.
ii) Instrument panel (instrument panel) skin, door skin, ceiling skin, console skin, etc., which are processed by pulverizing the composition of the present invention into a powder form of 1.0 mm or less and powder slush molding.
iii) Various skins such as a handle skin, a console skin, an armrest skin, a shift knob skin, a parking lever grip skin, an assist grip skin, and a seat adjust grip skin, which are molded and processed by injection molding of the composition of the present invention. In this case, the base material of the olefinic resin and the skin of the present invention can be integrally molded by sequential injection molding and simultaneous injection molding with an olefinic resin such as polypropylene. Further, at the time of injection molding, foaming may be performed using a foaming agent to form a foam.

(Polymerization Example 1; Synthesis of Syndiotactic Propylene / Ethylene Copolymer)
750 ml of heptane was added at room temperature to a 1.5 liter autoclave that had been dried under reduced pressure and purged with nitrogen, and then a 1.0 mmol / ml toluene solution of triisobutylaluminum converted to aluminum atoms, the amount was 0.3 0.3 ml was added so that it might become a millimol, and 50.7 liters (25 degreeC, 1 atmosphere) of propylene was charged with stirring, temperature rising was started, and it reached 30 degreeC. Thereafter, the inside of the system was pressurized to 5.5 kg / cm ² G with ethylene, and a heptane solution of diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride synthesized by a known method (0.0002 mM / ml). And 3.75 ml of triphenylcarbenium tetra (pentafluorophenyl) borate in toluene (0.002 mM / ml) were added to start copolymerization of propylene and ethylene. The catalyst concentration at this time was 0.001 mmol / liter of diphenylmethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride and 0.004 mmol / liter of triphenylcarbenium tetra (pentafluorophenyl) borate with respect to the entire system. Liters.

During the polymerization, ethylene was continuously supplied to maintain the internal pressure at 5.5 kg / cm ² G. 30 minutes after starting the polymerization, the polymerization reaction was stopped by adding methyl alcohol. After depressurization, the polymer solution is taken out, and the polymer solution is washed with a ratio of 1: 1 of “an aqueous solution in which 5 ml of concentrated hydrochloric acid is added to 1 liter of water” to remove the catalyst residue. The water phase was transferred. After this catalyst mixed solution was allowed to stand, the aqueous phase was separated and removed, and further washed twice with distilled water, and the polymerization liquid phase was separated into oil and water. Subsequently, the polymer liquid phase separated from oil and water was brought into contact with 3 times the amount of acetone under strong stirring to precipitate a polymer, and then sufficiently washed with acetone, and the solid part (copolymer) was collected by filtration. It dried for 12 hours at 130 degreeC and 350 mmHg under nitrogen circulation.

  The propylene / ethylene copolymer obtained as described above has an intrinsic viscosity [η] measured in decalin at 135 ° C. of 2.4 dl / g, an SP value of 0.94, and a glass transition temperature of − It was 28 ° C., the ethylene content was 24 mol%, and the molecular weight distribution (Mw / Mn) measured by GPC was 2.9. The degree of crystallinity measured by wide angle X-ray diffraction was less than 5%.

[Example 1]
25 parts by weight of isotactic polypropylene (homopolymer, MFR (230 ° C., 2.16 kg load, the same applies hereinafter) 12 (g / 10 min), crystallinity 55%), ethylene / propylene / 5-ethylidene-2-norbornene Copolymer rubber oil extended (oil extended 40 parts (oil: mineral oil-based paraffin oil), Mooney viscosity ML1 + 4 (100 ° C) 70, ethylene content 79 mol%, iodine number 11, crystallinity less than 5% ), 75 parts by weight of pellets, 0.2 parts by weight of 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane as a crosslinking agent, and 0.3 parts by weight of divinylbenzene as a crosslinking aid. The mixture was sufficiently mixed with stirring and supplied to a twin screw extruder set at 160 ° C. to 220 ° C. to perform dynamic crosslinking to produce pellets of thermoplastic elastomer (A-1).

For 100 parts by weight of the thermoplastic elastomer (A-1) pellets,
35 parts by weight of propylene / ethylene copolymer and syndiotactic polypropylene (homopolymer, MFR (230 ° C., 2.16 kg load, the same applies hereinafter) 8 (g / 10 min), crystallinity obtained in Polymerization Example 1 23%) 10 parts by weight and 1 part by weight of carbon black masterbatch (for coloring in black) were kneaded by a twin screw extruder set at 230 ° C. to obtain pellets of composition (I).

  The resulting composition (I) pellets were extruded with an extrusion sheet molding machine with a T-die set at a die temperature of 210 ° C., and a sheet with a texture was passed between a grain roll (roll temperature 90 ° C.) and a pinch roll installed immediately after the die. Got. The thickness of the embossed sheet is 0.5 mm, and the maximum depth of the embossed sheet is 180 μm. This embossed sheet was subjected to convex vacuum forming using an instrument panel mold under the condition of a sample temperature of 145 ° C. The molded appearance was satisfactory with no particular problems.

In addition, a sheet that has not been vacuum formed is covered with a cotton canvas # 10 at the tip of a 470 g wear indenter made of 45R, SUS using a 2 mm-thick specimen using a Gakushin abrasion tester manufactured by Toyo Seiki. The sample was worn at 23 ° C., the number of reciprocations of 100 times, the reciprocation speed of 33 times / min, and the stroke of 100 mm, and the gloss change rate ΔGloss before and after that was determined as follows.
ΔGloss = (Gloss before wear−Gloss after wear) / Gloss before wear × 100
ΔGloss under the above conditions was 13%.

[Comparative Example 1]
With respect to 100 parts by weight of the thermoplastic elastomer (A-1) obtained in Example 1, a propylene / ethylene copolymer having an existing isotactic structure (the intrinsic viscosity [η] measured in decalin at 135 ° C. is 2). 0.5 dl / g, ethylene content 24 mol%, molecular weight distribution (Mw / Mn) measured by GPC is 3.0, crystallinity is less than 5%) and 35 parts by weight of isotactic polypropylene (homopolymer, MFR (230 2 ° C., 2.16 kg load, the same applies hereinafter) 8 (g / 10 min), crystallinity 55%) 10 parts by weight, carbon black masterbatch 1 part by weight (to color black) 2 It knead | mixed with the screw extruder and the pellet of composition (II) was obtained.

A sheet with a texture was formed from the resulting composition (II) pellets in the same manner as in Example 1, and convex vacuum forming was performed in the same manner as in Example 1. As for the molded appearance, uneven gloss was observed in some places. This is probably because the elongation was not uniform.
In addition, the gloss before and after the academic vibration wear test was measured in the same manner as in Example 1. ΔGloss was 35%.

[Example 2]
A grip was formed from the composition (I) pellet obtained in Example 1 by injection molding. A cotton canvas having a width of 3 cm was applied to the obtained grip, and a reciprocating wear test was performed 300 times with a load of 300 g as shown in FIG. The change before and after the test was visually evaluated according to the following criteria.

5 points: no scratches are observed 4 points: slight scratches are observed 3 points: obvious scratches are observed 2 points: the surface is shaved and worn 1 point: the surface is worn significantly The score is 4 It was a point.
[Comparative Example 2]
A grip was molded from the composition (II) pellet obtained in Comparative Example 1 by injection molding in the same manner as in Example 2. Further, a re-wear test was performed in the same manner as in Example 2, and changes before and after the test were visually evaluated. There were 2 points.

  According to the present invention, it is possible to propose an automobile interior skin member that is excellent in scratch resistance and wear resistance, and has excellent flexibility, heat resistance, and moldability.

Fig. 3 illustrates a reciprocating wear test.

Claims (7)

The weight ratio of the olefin resin (a) and the ethylene copolymer rubber (b) (when a + b = 100 parts by weight, (a) :( b) = 15-60: 85-40) is an essential component. An olefinic thermoplastic elastomer composition (A),
(C-1) a repeating unit derived from propylene;
(C-2) from at least one olefin selected from olefins having 2 to 20 carbon atoms other than propylene and, if necessary, (c-3) at least one polyene selected from conjugated polyenes and non-conjugated polyenes Consisting of repeating units led and
When the total amount of the unit (c-1) and the unit (c-2) is 100 mol%, the unit (c-1) is contained in an amount of 99 to 50 mol%, and the unit (c-2) In an amount of 1 to 50 mol%, and an amount of 0 to 30 mol% of the unit (c-3) with respect to 100 mol% of the total amount of the units (c-1) and (c-2) And a syndiotactic propylene copolymer (C) having a syndiotactic structure having a syndiotacticity parameter (SP value) of 0.6 or more, the olefin-based thermoplastic elastomer composition (A) 100 An automobile interior skin member comprising a composition containing 5 to 200 parts by weight with respect to parts by weight , wherein the ethylene copolymer rubber (b) is crosslinked .
Here, the syndiotacticity parameter (SP value) is determined based on the ¹³ C-NMR spectrum of the syndiotactic propylene copolymer and the following formula (1): It is calculated | required as intensity | strength (area) ratio of side chain methyl group.
SP value = signal area of the third region (19.5-20.3 ppm) / {signal area of the first region (21.0-21.9 ppm) + signal area of the second region (20.3-21.0 ppm) + third region (19.5-20.3) ppm) signal area} (1) 2. The automobile interior skin member according to claim 1, comprising 20 to 200 parts by weight of a polypropylene resin (D) with respect to 100 parts by weight of the syndiotactic propylene copolymer (C) . The automobile interior skin member according to claim 2 , wherein the polypropylene resin (D) has a syndiotactic structure having a syndiotacticity parameter (SP value) of 0.6 or more .
Here, the syndiotacticity parameter (SP value) is determined based on the ¹³ C-NMR spectrum of the syndiotactic propylene copolymer and the following formula (1): It is calculated | required as intensity | strength (area) ratio of side chain methyl group.
SP value = signal area of the third region (19.5-20.3 ppm) / {signal area of the first region (21.0-21.9 ppm) + signal area of the second region (20.3-21.0 ppm) + third region (19.5-20.3) ppm) signal area} (1) The automobile interior skin member according to any one of claims 1 to 3, wherein the interior skin is manufactured by vacuum molding, stamping molding, powder slush molding, or injection molding. Serial There syndiotactic propylene copolymer is an intrinsic viscosity measured at 135 ° C. in decalin (C) in the range of 0.1~10dl / g, gel permeation molecular weight distribution obtained by chromatography is 4 or less The automotive interior skin member according to any one of claims 1 to 4 , wherein the glass transition temperature is 30 ° C or lower. The syndiotactic propylene copolymer (C) is
(A) a transition metal complex represented by the following general formula (I) or (II):
(B) (B-1) a compound that reacts with the transition metal in (A) to form an ionic complex,
It is obtained in the presence of at least one catalyst system comprising (B-2) an organoaluminum oxy compound and (B-3) at least one compound selected from organoaluminum compounds. The automobile interior skin member according to any one of claims 1 to 5 .

(In the formulas (I) and (II), M represents Ti, Zr, Hf, Rn, Nd, Sm or Ru, and Cp1 and Cp2 represent cyclopentadienyl group, indenyl group and fluorenyl which are π-bonded to M. X ¹ and X ² represent an anionic ligand or a neutral Lewis base ligand, and Y represents a coordination containing a nitrogen atom, an oxygen atom, a phosphorus atom or a sulfur atom. Z represents a C, O, B, S, Ge, Si or Sn atom or a group containing these atoms.) The automobile interior skin member according to any one of claims 1 to 6, wherein the syndiotactic propylene copolymer (C) is crosslinked.

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