JP2008174733A - Method for producing olefinic thermoplastic elastomer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing effectively an olefinic thermoplastic elastomer usable as a material for producing a molded article having good appearance. <P>SOLUTION: A method for producing an olefinic thermoplastic elastomer comprises kneading an olefin copolymer rubber (A) obtained by polymerizing ethylene, a 3-20C &alpha;-olefin, and a non-conjugated polyene, a volatile organic solvent (B), an olefinic resin (C), and a mineral oil softening agent (D) in an extruder, removing the volatile organic solvent (B) while continuing the kneading, then adding a crosslinking agent (E) and further removing the volatile organic solvent (B) while kneading in the extruder. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a method for producing an olefinic thermoplastic elastomer.

  Thermoplastic elastomers do not require a vulcanization process and can be processed with a molding machine for processing ordinary thermoplastic resins. Used in Among thermoplastic elastomers, olefinic thermoplastic elastomer obtained by kneading olefinic copolymer rubber obtained by polymerizing ethylene, α-olefin having 3 to 20 carbon atoms and non-conjugated polyene and olefinic resin Is widely used as an environmentally friendly material that is lightweight and recyclable and does not contain chlorine.

  As a method for producing an olefinic thermoplastic elastomer, a method is known in which an olefinic copolymer rubber and an olefinic resin are kneaded by a closed kneader exemplified by a Banbury mixer. However, since this method uses a batch kneader such as a Banbury mixer, there is a problem in that productivity is poor and the method is not efficient.

  As a method for solving such a problem, a method of kneading an olefin copolymer rubber and an olefin resin with a twin screw extruder is known. For example, in Patent Document 1, a mixture mainly composed of an olefin copolymer rubber and a polyolefin resin is directly supplied to a twin screw extruder having an L / D of 20 or more, and the temperature at which the half-life is 1 minute is set. When performing dynamic heat treatment in the presence of an organic peroxide of 160 ° C. or higher, the temperature of the cylinder on the raw material supply port side of the twin screw extruder is 130 ° C. over 10 times the diameter of the twin screw extruder. The temperature of the die is controlled at a temperature of ˜155 ° C., and the cylinder temperature on the die side other than the cylinder portion controlled at the temperature is controlled at 180 ° C. to 280 ° C. over a length 10 times longer than the diameter of the twin screw extruder. A method for producing an olefinic thermoplastic elastomer composition is described.

Japanese Patent Laid-Open No. 5-220825

  However, when only the olefin copolymer rubber, the olefin resin and the cross-linking agent are supplied to the extruder and kneaded at the same time, the molded product formed using the olefinic thermoplastic elastomer is not suitable. As a result, a molded product having a good appearance may not be obtained.

  An object of this invention is to provide the method of manufacturing efficiently the olefin type thermoplastic elastomer used as the material for manufacturing a molded article with a favorable external appearance.

  That is, the present invention relates to an olefin copolymer rubber (A), a volatile organic solvent (B), an olefin resin (C) obtained by polymerizing ethylene, an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene. ) And mineral oil softener (D) while removing the volatile organic solvent (B) while kneading in an extruder, then adding a cross-linking agent (E), and further volatilizing while kneading in an extruder. This is a method for producing an olefinic thermoplastic elastomer by removing the porous organic solvent (B).

  According to the production method of the present invention, it is possible to efficiently produce an olefinic thermoplastic elastomer that is a material for producing a molded article having a good appearance.

  In the present invention, an olefin copolymer rubber (A) obtained by polymerizing ethylene, an α-olefin having 3 to 20 carbon atoms and a non-conjugated polyene is used. The olefin copolymer rubber (A) in the present invention is an ethylene / α-olefin / non-conjugated polyene copolymer rubber having an A hardness of JIS K-6253 of 98 or less. Hereinafter, the term “ethylene unit” in the present invention means a structural unit derived from a monomer present in a rubber or resin obtained by polymerization.

  Examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 2-methylpropylene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene and the like; and combinations of two or more thereof can be exemplified. Among these, from the viewpoint of availability, propylene or 1-butene is preferable, and propylene is more preferable.

  Examples of the non-conjugated polyene include 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene. Chain non-conjugated dienes such as: cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinylnorbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2- Cyclic non-conjugated dienes such as norbornene and 6-chloromethyl-5-isopropenyl-2-norbornene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2 -Propenyl-2,2-norbornadiene, 4-ethylidene-8-me It can be exemplified triene such as Le 1,7 Nanojien. Of these, 5-ethylidene-2-norbornene or dicyclopentadiene is preferable.

  When the total of ethylene units, α-olefin units having 3 to 20 carbon atoms, and non-conjugated polyene units contained in the olefin copolymer rubber (A) is 100% by weight, the olefin copolymer rubber ( The amount of ethylene units contained in A) is usually 30 to 90% by weight, preferably 40 to 80% by weight, and the amount of α-olefin units having 3 to 20 carbon atoms is usually 5 to 70% by weight, Preferably it is 15 to 60% by weight. The amount of the non-conjugated polyene unit contained in the olefin copolymer rubber (A) is usually 0.1 to 30% by weight, preferably 0.1 to 20% by weight (the total of these three types of monomer units is 100% by weight). Specific examples of the olefin copolymer rubber (A) include ethylene / propylene / 5-ethylidene-2-norbornene copolymer, ethylene / propylene / dicyclopentadiene copolymer, ethylene / propylene / 1,4- Examples include hexadiene copolymer, and ethylene / propylene / 5-vinyl-2-norbornene copolymer; and combinations of two or more thereof. Among them, ethylene / propylene / 5-ethylene content of 40 to 80% by weight, propylene unit content of 15 to 55% by weight, and 5-ethylidene-2-norbornene unit content of 2 to 10% by weight Ethylidene-2-norbornene copolymer is preferred.

  The olefin copolymer rubber (A) can be obtained by polymerization by a known method. Examples of the polymerization method include a polymerization method in an inert solvent such as hexane, heptane, toluene, and xylene using a polymerization catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst.

The Mooney viscosity (ML _{1 + 4} 100 ° C.) of the olefin copolymer rubber (A) is preferably 10 to 350, more preferably 30 to 300. The olefinic thermoplastic elastomer obtained using the olefinic copolymer rubber (A) having a Mooney viscosity in the above range gives a molded product having excellent mechanical strength and a very good appearance when molded. be able to.

  The volatile organic solvent (B) in the present invention specifically includes aliphatic hydrocarbons such as pentane, hexane, heptane, octane, decane, dodecane, kerosene and their halogen derivatives, cyclohexane, methylcyclopentane, methylcyclohexane. And organic solvents such as alicyclic hydrocarbons such as alicyclic hydrocarbons and their halogen derivatives, aromatic hydrocarbons such as benzene, toluene and xylene, and halogen derivatives such as chlorobenzene. These organic solvents may be used alone or in combination. The volatile organic solvent (B) may be a solvent used when the olefin copolymer rubber (A) is polymerized in the solution polymerization method. From the viewpoint of affinity with the olefin copolymer rubber (A), the volatile organic solvent (B) may contain a monomer used when the olefin copolymer rubber (A) is polymerized. .

  The olefin-based resin (C) in the present invention is a resin obtained by polymerizing ethylene and / or α-olefin, for example, an ethylene-based resin containing 70% by weight or more of an ethylene unit or a propylene unit of 50% by weight. The propylene-type resin containing the above is mentioned.

  The propylene resin used as the olefin resin (C) in the present invention is a propylene homopolymer containing 50 to 100% by weight, preferably 80 to 100% by weight of propylene units, or propylene and ethylene and / or Or a random copolymer or a block copolymer with an α-olefin having 4 to 10 carbon atoms (for example, 1-butene, 1-hexene, 1-pentene, 1-octene and 4-methyl-1-pentene). Can be mentioned. Examples of the copolymer include an ethylene / propylene copolymer, a propylene / 1-butene copolymer, a propylene / 1-hexene copolymer, a propylene / 1-octene copolymer, and a propylene / ethylene / 1-butene copolymer. An ethylene / propylene / 1-hexene copolymer can be exemplified. As the olefin resin (C), it is preferable to use a propylene homopolymer, an ethylene / propylene copolymer or a propylene / 1-butene copolymer.

The case where the block copolymer is used in the case of using propylene and ethylene means a polymer produced by a production method comprising the following steps.
(1) A step of homopolymerizing propylene to produce polypropylene;
(2) A step of copolymerizing propylene and ethylene in the presence of the polypropylene.
Or (1) a step of homopolymerizing propylene to produce polypropylene;
(2) A step of removing unreacted propylene monomer and polymerizing by adding ethylene in the presence of the polypropylene.
In the former case, the resulting polymer is substantially a mixture of the polypropylene produced in step (1) and the propylene-ethylene copolymer produced in step (2).

  When the olefin resin (C) used in the present invention is a propylene resin, the propylene resin has a melt flow rate measured at a temperature of 230 ° C. under a load of 21.18 N according to JIS K6758 of 0.1 to 0.1. It is preferably 300 g / 10 minutes, and more preferably 0.5 to 200 g / 10 minutes.

  The ethylene resin used as the olefin resin (C) in the present invention includes (1) a homopolymer of ethylene or (2) ethylene and 3 to 3 carbon atoms, containing 70 to 100% by weight of ethylene units. 10 α-olefins (eg propylene, 1-butene, 1-pentene, 4-methyl-1-pentene and 1-hexene) and / or monomers having polar groups and carbon-carbon double bonds (eg , Vinyl acetate, acrylic acid ester and methacrylic acid ester). Preferred ethylene resins include high density polyethylene, low density polyethylene, ethylene / propylene copolymer, ethylene / 1-butene copolymer, ethylene / 1-pentene copolymer, ethylene / 4-methyl-1-pentene copolymer. Examples thereof include a polymer and an ethylene / 1-hexene copolymer.

  When the olefin-based resin (C) used in the present invention is an ethylene-based resin, the ethylene-based resin has a melt flow rate measured at a temperature of 190 ° C. under a load of 21.18 N according to JIS K6760. 300 g / 10 min is preferable, and 0.1 to 200 g / 10 min is more preferable.

The olefin resin (C) used in the present invention can be obtained by polymerization by a known method.
As the polymerization method, (1) polymerization in an inert solvent such as hexane, heptane, toluene, xylene using a polymerization catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst; (2) a liquid monomer (3) a method of polymerizing gaseous monomers (gas phase polymerization method); and (4) a combination thereof. The three-dimensional structure of the olefin resin (C) is not particularly limited, and examples of the three-dimensional structure include an isotactic structure, a syndiotactic structure, and a structure in which both of these structures are mixed. Among these, a propylene-based resin having an isotactic structure as a main structure is preferable.

As the mineral oil softening agent (D) in the present invention, the high molecular weight of petroleum having an average molecular weight of 300 to 1500 and a pour point of 0 ° C. or less, such as aroma mineral oil, naphthenic mineral oil, and paraffin mineral oil. A boiling fraction can be illustrated. Among these, paraffinic mineral oil is preferable.
The mineral oil softener (D) may be previously contained in the olefin copolymer rubber. In the rubber field, the olefin copolymer rubber containing a mineral oil softener is generally called an oil-extended rubber, and the mineral oil softener is called an extender oil.

  As a method for obtaining an olefin copolymer rubber containing a mineral oil softener, (1) a method of kneading them mechanically using a roll or a Banbury mixer, (2) an olefin copolymer A method of adding a mineral oil softening agent to the solution of the olefin copolymer rubber obtained in the production process of the combined rubber (A) and then removing the solvent by a method such as steam stripping can be exemplified.

  As the cross-linking agent (E) in the present invention, a cross-linking agent usually used for rubber cross-linking can be used, and organic peroxides, phenol resins, sulfur, sulfur-containing compounds, p-quinone, p-quinone di Examples include oxime derivatives, bismaleimide compounds, epoxy compounds, silane compounds, and amino resins. Of these, organic peroxides or phenol resins are preferred.

Dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (tertiary butyl peroxy) hexane, 2,5-dimethyl-di (tertiary butyl peroxy) hexyne as organic peroxides -3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tertiary Illustrates (butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tertiary butyl peroxybenzoate, tertiary butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tertiary butyl peroxide be able to. Among them, 2,5-dimethyl-2,5-di (tert-butylperoxy) -hexyne-3, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, 1,3-bis (tert 3-butylperoxyisopropyl) benzene is preferred, and 2,5-dimethyl-2,5-di (tertiarybutylperoxy) -hexyne-3 having a high decomposition temperature is particularly preferred.
The organic peroxide used in the present invention may be in any form such as liquid, powder, or pellet. In order to improve the dispersibility, it is more preferable to dilute with a diluent such as an inorganic filler, a mineral oil, or a solvent that is inert to the crosslinking reaction. Further, the addition method is more preferably added in a liquid state. Among these, paraffinic oil is a preferable diluent in consideration of its handleability and influence on products.

  In order to allow the crosslinking reaction to proceed uniformly and moderately, an organic peroxide and a crosslinking aid may be used in combination. As the crosslinking aid, polyfunctional compounds such as sulfur, methacrylate and maleimide can be blended. As crosslinking aids, sulfur, p-quinone dioxime, p, p'-dibenzoylquinone dioxime, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, Examples include trimethylolpropane trimethacrylate, diallyl phthalate, tetraallyloxyethane, triallyl isocyanurate, N, N'-m-phenylenebismaleimide, maleic anhydride, divinylbenzene, zinc diacrylate, and zinc dimethacrylate it can. Among these, N, N′-m-phenylenebismaleimide, p, p′-dibenzoylquinone dioxime, divinylbenzene, trimethylolpropane trimethacrylate, or triallyl isocyanurate is preferable. N, N'-m-phenylenebismaleimide can be used alone as a crosslinking agent.

式中、ｎは０〜１０の整数；ＸおよびＹはそれぞれ独立に水酸基、ハロゲン化アルキル基またはハロゲン原子であり；Ｒは炭素原子数１〜１５の飽和炭化水素基である。該化合物は、置換フェノールとアルデヒドとをアルカリ触媒で縮重合させることによって製造することができる。 Examples of the phenol resin used as the crosslinking agent (E) include compounds represented by the following formulas generally used as a crosslinking agent for rubber (see US Pat. Nos. 3,287,440 and 3,709,840). ):

In the formula, n is an integer of 0 to 10; X and Y are each independently a hydroxyl group, a halogenated alkyl group or a halogen atom; R is a saturated hydrocarbon group having 1 to 15 carbon atoms. The compound can be produced by polycondensation of a substituted phenol and an aldehyde with an alkali catalyst.

  Examples of the phenol resin include alkylphenol formaldehyde and brominated alkylphenol formaldehyde.

  When a phenol resin is used, it may be combined with a crosslinking accelerator in order to adjust the speed of the crosslinking reaction. Examples of crosslinking accelerators include metal halides such as stannous chloride and ferric chloride; and organic halides such as chlorinated polypropylene, butyl bromide rubber and chloroprene rubber.

  The phenolic resin is preferably used in combination with a metal oxide (for example, zinc oxide) and a dispersing agent such as stearic acid.

  In the present invention, components other than the olefin copolymer rubber (A), the volatile organic solvent (B), the olefin resin (C), the mineral oil softener (D) and the crosslinking agent (E), such as talc and An inorganic filler such as calcium carbonate; an additive such as a flame retardant, a plasticizer, an antistatic agent, a heat and light resistance stabilizer, an antiaging agent, and a release agent; or a pigment may be used in combination. These may be blended in olefin copolymer rubber (A) or olefin resin (C), olefin copolymer rubber (A), volatile organic solvent (B) olefin resin ( C) and mineral oil softener (D), or olefin copolymer rubber (A), volatile organic solvent (B), olefin resin (C) mineral oil softener (D) and crosslinking agent (E). You may add separately when kneading in an extruder.

In the present invention, the olefin copolymer rubber (A), the volatile organic solvent (B), the olefin resin (C), and the mineral oil softener (D) are kneaded in the extruder while kneading. This is a method for producing an olefinic thermoplastic elastomer by removing the organic solvent (B), then adding the crosslinking agent (E), and further removing the volatile organic solvent (B) while kneading in an extruder. .
If only three components of olefin copolymer rubber, olefin resin, and cross-linking agent are supplied to the extruder and kneaded together as in the past, the temperature rises rapidly due to shearing heat generation, and the cross-linking reaction is abrupt. As a result, when the olefinic thermoplastic elastomer obtained was molded, the molded product had a poor appearance.
As in the present invention, the volatile organic rubber (A), the volatile organic solvent (B), the olefinic resin (C) and the mineral oil softener (D) are kneaded in an extruder while the volatile organic is used. The solvent (B) is removed, then the cross-linking agent (E) is added, and the volatile organic solvent (B) is removed while kneading in an extruder to suppress shearing heat generation. Since the rapid increase in temperature can be suppressed even by the latent heat of vaporization, an olefinic thermoplastic elastomer suitable for the production of a molded article having a good appearance can be obtained.

  The proportions of the olefin copolymer rubber (A), volatile organic solvent (B), olefin resin (C), mineral oil softener (D) and cross-linking agent (E) supplied to the extruder are The volatile organic solvent (B) is usually 1 part by weight or more, preferably 5 parts by weight or more, more preferably 11 parts by weight or more, relative to 100 parts by weight of the polymer rubber (A). The amount is more preferably at least part by weight, and most preferably at least 20 parts by weight. The upper limit of the addition amount of the volatile organic solvent (B) is usually 50 parts by weight or less with respect to 100 parts by weight of the olefin copolymer rubber (A).

  The ratio of the olefin resin (C) to 100 parts by weight of the olefin copolymer rubber (A) is usually 5 to 150 parts by weight, preferably 10 to 140 parts by weight, and 15 to 120 parts by weight. More preferably.

  The ratio of the mineral oil softening agent (D) to 100 parts by weight of the olefin copolymer rubber (A) is usually 1 to 300 parts by weight, from the viewpoint of the balance between flexibility and tackiness of the resulting olefinic thermoplastic elastomer. 5 to 200 parts by weight is preferable.

  The addition amount of the crosslinking agent (E) is preferably 0.01 to 20 parts by weight and more preferably 0.05 to 10 parts by weight with respect to 100 parts by weight of the olefin copolymer rubber (A). Preferably, it is 0.05-5 weight part. By making the addition amount of a crosslinking agent (E) into the said range, it becomes an olefin type thermoplastic elastomer excellent in the balance of elastic recovery property and a softness | flexibility.

  When the crosslinking aid is added, the addition amount is preferably 0.01 to 10 parts by weight, and 0.05 to 5 parts by weight with respect to 100 parts by weight of the olefin copolymer rubber (A). It is more preferable.

  In the production method of the present invention, the olefinic thermoplastic elastomer may be produced by a single extruder, or a plurality of extruders may be connected and used. The extruder to be used is preferably a twin screw extruder. Examples of the twin screw extruder include those in which the rotational directions of the two screws are the same direction, those in different directions, those in which the two screws are completely or partially engaged, and those in which they are not engaged. However, among these, those in which the screw rotation direction is the same direction and the two screws are completely or partially engaged are preferable.

  In the present invention, it is not necessary to supply the olefin copolymer rubber (A), the volatile solvent (B), the olefin resin (C) and the mineral oil softener (D) to the extruder at the same time. And a step of kneading these four components simultaneously is necessary. The extruder used when kneading these four components and the four components with the addition of the crosslinking agent (E) has one or more, preferably two or more vents for releasing the volatile organic solvent (B). It must be a vented extruder. Moreover, when adding a liquid crosslinking agent (E), although a plunger pump etc. are normally used, there is no problem even if it uses any pump. When the solid crosslinking agent (E) such as powder or pellets is added, it can be added by a feeder or the like.

  As a method for producing an olefinic thermoplastic elastomer using one extruder, an olefinic copolymer rubber (A), a volatile organic solvent (B), an olefinic resin (C) and a mineral oil softener ( D) is supplied to the extruder from one supply port on the upstream side, and the volatile organic solvent (B) is removed from the vent while kneading in the extruder, and the crosslinking agent is supplied from the downstream supply port. A method of adding (E) and further removing the volatile organic solvent (B) while kneading in an extruder may be mentioned.

  As another method for producing an olefinic thermoplastic elastomer using one extruder, an olefinic copolymer rubber (A), a volatile organic solvent, using a vented extruder having a plurality of supply ports (B) and the mineral oil softening agent (D) are supplied to the extruder from the upstream supply port, the olefin resin (C) is supplied from the downstream supply port, and the volatile property is obtained while kneading in the extruder. When the organic solvent (B) is removed from the vent, the cross-linking agent (E) is added from the supply port on the downstream side, and the volatile organic solvent (B) is removed while kneading in an extruder. A method is mentioned. The olefin resin (C) may be divided and supplied from two or more supply ports. In this method, as illustrated in FIG. 2, a dispersion liquid in which an olefin copolymer rubber (A) polymerized in a polymerization tank (12) is dispersed in a polymerization solvent is directly supplied to an extruder (19). May be. In such a case, the polymerization solvent becomes the volatile organic solvent (B). When supplying the dispersion liquid in which the olefin copolymer rubber (A) is dispersed in the polymerization solvent directly to the extruder, the concentration of the dispersion liquid to be supplied may be adjusted by removing the solvent to some extent in advance. Mineral oil softener (D) supply pump (13) supplies mineral oil softener (D), olefin resin (C) supply port (15) supplies olefin resin (C), and vent (16) volatilizes. Kneading with an extruder (19) while removing the organic solvent. Further, the cross-linking agent (E) is added from the cross-linking agent (E) supply port (14), and the volatile organic solvent is removed from the vents (17) and (18) while kneading to obtain an elastomer.

As a method for producing an olefinic thermoplastic elastomer using two extruders, a mixture obtained by supplying an olefinic copolymer rubber (A) and a volatile organic solvent (B) to the first extruder and mixing them is used. Is supplied to the second extruder to which the first extruder is connected, and further, the mineral oil softener (D) and the olefin resin (C) are supplied to the second extruder and kneaded. The volatile organic solvent (B) is removed from the vent, then the cross-linking agent (E) is added from the supply port provided on the downstream side of the second extruder, and the volatile organic solvent is further removed from the vent while kneading. The method of removing (B) is mentioned. The mineral oil softener (D) may be supplied to the first extruder. When two connected extruders are used, an extruder without a vent is used as the first extruder.
The second extruder has at least two supply ports, and has one or more vents between the upstream supply port and the downstream supply port, and more downstream than the downstream supply port. Use a vented extruder. Thus, also when using two extruders, the dispersion concentration of the dispersion liquid in which the olefin copolymer rubber (A) polymerized in the polymerization tank was dispersed in the polymerization solvent was adjusted as necessary. Thereafter, it may be supplied directly to the first extruder.

  In the case of producing an olefinic thermoplastic elastomer using three extruders, an extruder in which the first extruder and the second extruder are connected to the third extruder is used. The first extruder is supplied with the olefin copolymer rubber (A), the volatile organic solvent (B), and the mineral oil softener (D). The olefin resin (C) is supplied to the second extruder. The volatile organic solvent (B) is removed from the vent while these are joined and kneaded in the third extruder, then the cross-linking agent (E) is added, and the volatile organic solvent is further kneaded in the extruder. By removing (B), an olefinic thermoplastic elastomer can be obtained. In this case, an extruder without a vent is used as the first extruder, and a vented extruder is used as the third extruder. The second extruder may or may not have a vent. Thus, even when using three extruders, the dispersion concentration of the dispersion liquid in which the olefin copolymer rubber (A) polymerized in the polymerization tank was dispersed in the polymerization solvent was adjusted as necessary. Later, it can be fed directly to the first extruder.

  In the present invention, it is preferable to produce an olefinic thermoplastic elastomer using two connected extruders. The case of using two extruders will be described in more detail with reference to FIG. FIG. 3 shows an apparatus in which a first extruder and a second extruder are connected. Further, the olefin copolymer rubber (A) and the volatile organic solvent (B) are directly fed from the polymerization tank (21) of the olefin copolymer rubber through a concentration adjusting step (not shown) directly to the first extruder. (28) can be supplied. In the first extruder (28), the olefin copolymer rubber (A) and the volatile organic solvent (B) are kneaded and then supplied to the second extruder (20). A mineral oil softener (D) is supplied from a mineral oil softener (D) supply pump (26), and an olefin resin (C) is supplied from an olefin resin (C) supply port (22). ) To remove volatile organic solvents. Further, an elastomer can be obtained by adding the crosslinking agent (E) from the crosslinking agent (E) supply port (27) and removing the volatile organic solvent from the vents (24) and (25) while kneading.

  The olefinic thermoplastic elastomer produced by the production method of the present invention includes bumper parts, roof moldings, side moldings, body panels, side shields, glass run channels, instrument panel skins, door skins, ceiling skins, weather strip materials, hoses. And automotive parts such as steering wheels; electrical parts such as wire coverings, connectors, and cap plugs; footwear such as soles and sandals; such as swimming fins, underwater glasses, golf club grips, and baseball bat grips Leisure goods; used for gaskets, various gaskets and sheets for civil engineering and construction, waterproof cloth, garden hoses, belts, and industrial miscellaneous goods such as industrial packing.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these.

Examples 1-3
(1) Raw material As the olefin copolymer rubber (A), a veiled esprene 553 (manufactured by Sumitomo Chemical Co., Ltd.) crushed by a rubber crusher was used (hereinafter referred to as EPDM). The rubber contains ethylene-propylene having an ethylene unit content of 58.0% by weight, a propylene unit content of 37.5% by weight, and a 5-ethylidene-2-norbornene unit content of 4.5% by weight. -5-ethylidene-2-norbornene copolymer rubber.
As the volatile organic solvent (B), a mixed solvent in which hexane and 5-ethylidene-2-norbornene were mixed at a weight ratio of hexane: 5-ethylidene-2-norbornene = 15: 1 (hereinafter referred to as mixed solvent and Called).
As the olefin resin (C), Nobrene U501E1 (manufactured by Sumitomo Chemical Co., Ltd.) was used (hereinafter referred to as PP). The resin is a homopolymer of propylene having a melt flow rate of 130 g / 10 min and a melting point of 160 ° C. measured at 230 ° C. under a load of 21.18 N.
As mineral oil softener (D), PW-100 (made by Idemitsu Kosan Co., Ltd.) was used (hereinafter referred to as softener). The softener is a paraffinic mineral oil having an average molecular weight of 545 and a pour point of −12.5 ° C.
As a crosslinking agent (E), 2,5-dimethyl-2,5-di (t-butylperoxy) hexane was diluted to 10% with PW-100 (produced by Idemitsu Kosan Co., Ltd.), which is a paraffinic oil. A brand name APO-10DL manufactured by Yakuzo Co., Ltd. was used.

(2) Apparatus The olefin type thermoplastic elastomer was manufactured using the apparatus with which the 1st extruder and the 2nd extruder as shown in FIG. 1 were connected. The first extruder was a twin-screw extruder having a trade name of TEX65XCT manufactured by Nippon Steel, Ltd., and had a cylinder inner diameter of 69 mm and a ratio of the cylinder length to the cylinder inner diameter (L / D) of 31.5. Further, a cooling water pipe was provided inside the cylinder, and a heater for controlling the temperature was provided outside the cylinder. The second extruder was a twin screw extruder having a trade name of TEX30α manufactured by Nippon Steel Works, and had a cylinder inner diameter of 32 mm and a ratio of the cylinder length to the cylinder inner diameter (L / D) of 42. Further, a cooling water pipe was provided inside the cylinder, and a heater for controlling the temperature was provided outside the cylinder.

(3) Evaluation of molded product A single-screw extruder having a cylinder inner diameter of 25 mm and made of union plastic and having a full flight type screw and a T die, using the pellets of the olefinic thermoplastic elastomer obtained in the examples as raw materials. An extruded sheet having a thickness of 0.2 mm was prepared using (USV type).
The appearance of the obtained sheet was visually observed for the number and size of bumps, ○ when there was almost no bumps and good appearance, △ when there were some bumps but there was no practical problem, and The case where there were many poor appearances was marked with x.

[Example 1]
EPDM and PP were continuously fed from the feed port (3) of the first extruder (1) at a feed rate of 20 kg / hr of EPDM and 8.6 kg / hr of PP using a gravimetric feeder. Further, the mixed solvent was continuously supplied from the supply pump (4) of the first extruder at a supply rate of 4 kg / hr, and the softener was supplied from the supply pump (5) at a supply rate of 6.8 kg /. The screw speed of the first extruder (1) was set to 50 rpm, and the cylinder temperature was set to 130 ° C. In the first extruder, EPDM, PP, a mixed solvent, and a softening agent were continuously fed to the second extruder (2) through the feed port (6). The second extruder (2) was set to a screw rotation speed of 400 rpm and a cylinder temperature of 180 ° C. In the second extruder (2), the mixed solvent was removed from the vent (7) and the vent (11) while kneading EPDM, PP, mixed solvent, and softener. Further, the crosslinking agent is supplied from the supply pump (10) of the second extruder at a supply rate of 0.06 kg / hr (0.6 kg / hr for APO-10DL) and volatilized from the vent (9) while kneading. The organic solvent was removed, and the kneaded product was cut with a pelletizer provided in the second extruder to obtain a pellet-shaped olefinic thermoplastic elastomer.

[Example 2]
Except that the master batch of the following composition which mix | blended various additives, such as crosslinking adjuvant, was added at 0.274 kg / hr from the supply port (3) of the 1st extruder (1) using the weight type feeder. The same operation as in Example 1 was performed. The results are shown in Table 1.
<Master batch composition>
Crosslinking aid: Trimethylolpropane trimethacrylate (trade name High Cloth MS50 manufactured by Seiko Chemical Co., Ltd.) (concentration in masterbatch 40%)
Antioxidant: Pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name Irganox 1010 manufactured by Ciba Specialty Chemicals) (concentration in master batch: 10%)
Light-resistant stabilizer: 2- (2-hydroxy-3-t-butyl-5-methylphenyl) -5-chlorobenzotriazole (trade name Sumisorb 300 manufactured by Sumitomo Chemical Co., Ltd.) (concentration in master batch 20%)
Light-resistant stabilizer: 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and dimethyl succinate condensate (trade name Tinuvin 622 manufactured by Ciba Specialty Chemicals) (concentration in masterbatch) 20%)
Lubricant: Oleic acid amide (trade name Denon SL-12, manufactured by Maruhishi Oil Chemical Co., Ltd.) (concentration in masterbatch 10%)

[Example 3]
The same procedure as in Example 1 was performed except that the supply rate of the mixed solvent was changed to 2 kg / hr. The results are shown in Table 1.

Examples 4 and 5, Comparative Example 1
(1) Raw material A bale-shaped esprene 671F (manufactured by Sumitomo Chemical Co., Ltd.) pulverized with a rubber pulverizer as a mixture of an olefin copolymer rubber (A) and a mineral oil softener (D). (Hereinafter referred to as EPDM-2). The mixture contains ethylene-propylene having an ethylene unit content of 58.8% by weight, a propylene unit content of 37.7% by weight, and a 5-ethylidene-2-norbornene unit content of 3.5% by weight. 100 parts by weight of 5-ethylidene-2-norbornene copolymer rubber and 70 parts by weight of paraffinic mineral oil (PW-380 manufactured by Idemitsu Kosan Co., Ltd., average molecular weight is 746, pour point is −15 ° C.) It is a mixture of
As the volatile organic solvent (B), a mixed solvent in which hexane and 5-ethylidene-2-norbornene were mixed at a weight ratio of hexane: 5-ethylidene-2-norbornene = 15: 1 was used (as described above, the mixed solvent Called).
As the olefin resin (C), Nobrene FS2011DG3 (manufactured by Sumitomo Chemical Co., Ltd.) (hereinafter referred to as PP-2) and Sumikasen G201 (manufactured by Sumitomo Chemical Co., Ltd.) (hereinafter referred to as LDPE) were used. . The PP-2 is a propylene homopolymer having a melt flow rate of 2.5 g / 10 minutes and a melting point of 160 ° C. measured at 230 ° C. under a load of 21.18 N. The LDPE is a low density polyethylene polymer having a melt flow rate of 2 g / 10 minutes measured at 190 ° C. and a load of 21.18 N.
As a crosslinking agent (E), 2,5-dimethyl-2,5-di (t-butylperoxy) hexane was diluted to 10% with PW-100 (produced by Idemitsu Kosan Co., Ltd.), which is a paraffinic oil. A brand name APO-10DL manufactured by Yakuzo Co., Ltd. was used.

(2) Apparatus The olefin type thermoplastic elastomer was manufactured using the apparatus with which the 1st extruder and the 2nd extruder as shown in FIG. 4 were connected. The first extruder was a twin-screw extruder having a trade name of TEX65XCT manufactured by Nippon Steel, Ltd., and had a cylinder inner diameter of 69 mm and a ratio of the cylinder length to the cylinder inner diameter (L / D) of 31.5. Further, a cooling water pipe was provided inside the cylinder, and a heater for controlling the temperature was provided outside the cylinder. The second extruder was a twin screw extruder having a trade name of TEX30α manufactured by Nippon Steel Works, and had a cylinder inner diameter of 32 mm and a ratio of the cylinder length to the cylinder inner diameter (L / D) of 52.5. Further, a cooling water pipe was provided inside the cylinder, and a heater for controlling the temperature was provided outside the cylinder.

[Example 4]
EPDM-2 was blended with various additives such as 25 kg / hr, PP-2 and LDPE, and a crosslinking aid from the feed port (31) of the first extruder (29) using a gravimetric feeder. The master batch was continuously fed from the feed port (39) of the second extruder (30) at a feed rate of 5.6 kg / hr, 3.4 kg / hr, and 0.374 kg / hr using a gravimetric feeder. . Further, the mixed solvent was continuously supplied from the supply pump (32) of the first extruder at a supply rate of 5 kg / hr. The screw speed of the first extruder (29) was set to 50 rpm, and the cylinder temperature was set to 130 ° C. In the first extruder, EPDM, PP, LDPE, and mixed solvent were continuously fed to the second extruder (30) through the feed port (38). The second extruder (30) was set to a screw rotation speed of 400 rpm and a cylinder temperature of 180 ° C. In the second extruder (30), the mixed solvent was removed from the vent (34) and the vent (37) while kneading EPDM, PP, LDPE, and the mixed solvent. Further, the crosslinking agent is supplied from the supply pump (40) of the second extruder at a supply rate of 0.055 kg / hr (0.55 kg / hr in APO-10DL) and volatilized from the vent (36) while kneading. The organic solvent was removed, and the kneaded product was cut with a pelletizer provided in the second extruder to obtain a pellet-shaped olefinic thermoplastic elastomer. The results are shown in Table 2.

<Master batch composition>
Crosslinking aid: Trimethylolpropane trimethacrylate (trade name High Cloth MS50 manufactured by Seiko Chemical Co., Ltd.) (concentration in masterbatch 40%)
Antioxidant: Pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name Irganox 1010 manufactured by Ciba Specialty Chemicals) (concentration in master batch: 10%)
Light-resistant stabilizer: 2- (2-hydroxy-3-t-butyl-5-methylphenyl) -5-chlorobenzotriazole (trade name Sumisorb 300 manufactured by Sumitomo Chemical Co., Ltd.) (concentration in master batch 20%)
Light-resistant stabilizer: 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-piperidinol and dimethyl succinate condensate (trade name Tinuvin 622 manufactured by Ciba Specialty Chemicals) (concentration in masterbatch) 20%)
Lubricant: Oleic acid amide (trade name Denon SL-12, manufactured by Maruhishi Oil Chemical Co., Ltd.) (concentration in masterbatch 10%)

[Example 5]
The same procedure as in Example 4 was performed except that the supply rate of the mixed solvent was changed to 2.5 kg / hr. The results are shown in Table 2.

[Comparative Example 1]
The same operation as in Example 4 was performed except that the mixed solvent was not supplied. The results are shown in Table 2.

It is the schematic of the twin-screw extruder with a vent used in Examples 1-3 of this invention. It is the schematic of the other extruder used by this invention. It is the schematic of the other extruder used by this invention. It is the schematic of the twin-screw extruder with a vent used in Example 4, 5 and Comparative Example 1 of this invention.

Explanation of symbols

1: First extruder 2: Second extruder 3: Feed port 4: Mixed solvent (B) feed pump 5: Mineral oil softener (D) feed pump 6: Feed port 7: Vent 8: Vent 9: Vent 10 : Crosslinker (E) supply pump 11: Vent 12: Olefin copolymer rubber polymerization tank 13: Mineral oil softener (D) supply pump 14: Crosslinker supply (E) pump 15: Olefin resin (C) supply Port 16: Vent 17: Vent 18: Vent 19: Extruder 20: Second extruder 21: Olefin copolymer rubber polymerization tank 22: Olefin resin (C) supply port 23: Vent 24: Vent 25: Vent 26 : Mineral oil softener (D) supply pump 27: crosslinker (E) supply pump 28: first extruder 29: first extruder 30: second extruder 31: supply port 32: mixed solvent (B) supply pump 33: Mineral oil softener (D) supply pump 4: Vent 35: Vent 36: Vent 37: Vent 38: supply port 39: supply port 40: crosslinking agent (E) supply pump

Claims (3)

  Olefin copolymer rubber (A), volatile organic solvent (B), olefin resin (C) and mineral oil softening obtained by polymerizing ethylene, α-olefin having 3 to 20 carbon atoms and non-conjugated polyene The volatile organic solvent (B) is removed while kneading the agent (D) in an extruder, then the crosslinking agent (E) is added, and the volatile organic solvent (B) is further kneaded in the extruder. ) To produce an olefinic thermoplastic elastomer.   The method for producing an olefinic thermoplastic elastomer according to claim 1, wherein 100 parts by weight of the olefinic copolymer rubber (A) and 100 parts by weight of the olefinic copolymer rubber (A) are volatile organic solvents ( 11) to 50 parts by weight of B), 5 to 150 parts by weight of olefin resin (C), and 1 to 300 parts by weight of mineral oil softener (D) are mixed in the extruder while kneading the above volatile organic. The solvent (B) is removed, and then the crosslinking agent (E) is added in an amount of 0.01 to 20 parts by weight with respect to 100 parts by weight of the olefin copolymer rubber (A). A method for producing an olefinic thermoplastic elastomer by removing the porous organic solvent (B).   The method for producing an olefinic thermoplastic elastomer according to claim 1 or 2, wherein the olefinic resin (C) is a propylene resin.

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