JP2507241B2 - Method for producing thermoplastic elastomer-like composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention comprises two components, a rubber component of ethylene-propylene copolymer rubber and ethylene-propylene-non-conjugated diene copolymer rubber, and a resin component such as polyolefin resin and modified polyolefin resin. The present invention relates to a method for dynamically heat-treating a mixture containing a softening agent to crosslink the mixture to produce a thermoplastic elastomer composition.

[0002]

2. Description of the Related Art A thermoplastic elastomer obtained by dynamically heat-treating a compound containing a resin, a rubber and a rubber curing agent in a molten state (dynamic vulcanization) is known. Examples of producing a thermoplastic elastomer by such a method include JP-B-53-34210, 55-14099, and 55-1844.
8, 55-21050, 58-46138, 61-18
581, 63-1336, 63-34896, 63-4
6103, 64-4536, JP-A-52-73950,
54-137040, 56-45936, 56-143
233, 57-5751, 57-5753, 60-15
6738 and U.S. Pat. No. 4,288,570.

The manufacturing method described in these known documents is a manufacturing method in which a resin component and a rubber component are kneaded in a molten state mainly using a Banbury mixer,
Since it is a batch system, it is not economical.

On the other hand, as a method for producing a continuously partially crosslinked thermoplastic elastomer, a method has been proposed in which particulate rubber is directly supplied to an extruder (JP-A-58-2).
5340, 58-152023).

However, in these production methods, when a large amount of a softening agent is blended, it is difficult to mix them in an extruder and dynamically heat-treat them. After that, it is not economical because it is required to perform a heat treatment dynamically with the resin.

[0006]

SUMMARY OF THE INVENTION The present invention provides a resin component,
In a method for producing a thermoplastic elastomer obtained by dynamically heat-treating a mixture of a rubber component and a softening agent, stable production is possible even if a large amount of the softening agent is mixed, and by adopting a continuous process, It is to provide an economical manufacturing method.

[0007]

In order to solve the above-mentioned problems, the present inventors (a) have a bulk specific gravity of 0.3 or less and a maximum maximum length of 10 m.
m or less, the maximum length of the number average is powdery in 1mm or less ethylene - propylene copolymer rubber or ET styrene -
Propylene-non-conjugated diene copolymer rubber or a mixture thereof 20 to 80 parts by weight, (b) a polyolefin resin, a modified polyolefin resin or a mixture thereof 80 to 20 parts by weight, and (c) a softening agent of component (a) 5 to 100 parts by weight
Of the three components of 200 parts by weight , the component (c) is replaced with the component (a)
The component (a) is directly fed to the twin-screw extruder through a feed port different from the component (b) and is dynamically heat-treated in the twin-screw extruder using a crosslinking agent. The present invention has been accomplished by finding a method for producing a thermoplastic elastomer-like composition characterized by cross-linking a). Hereinafter, the present invention will be described in detail.

In the present invention, a powdery ethylene-propylene copolymer rubber, a powdery ethylene-propylene-non-conjugated diene copolymer rubber or a mixture thereof (hereinafter referred to as a rubber component or component (a)) and a polyolefin. It is necessary to use a resin and / or a modified polyolefin resin (hereinafter referred to as a resin component or component (b)) and a softening agent.

The ethylene-propylene copolymer rubber (hereinafter abbreviated as EPM) used in the present invention is a polymer of ethylene and propylene, and ethylene / propylene is 40/60 to 92/8, preferably 45. / 55-8
It is preferably copolymerized in a weight ratio of 0/20.
Such EPM includes those which can be produced by a known method. The preferred embodiment is that the EPM has a high molecular weight and is partially crystalline. More preferably M at 230 ° C
FI is less than 0.01 and X-ray crystallinity is 5%
That is all. It is easy to maintain the powder property of EPM because it has crystallinity.
Since it becomes possible to improve the oil absorption of the softening agent when softening PM, such an EPM is preferable because the applicability of the present production method is significantly enhanced.

The ethylene-propylene-diene copolymer rubber (hereinafter referred to as EPDM) used in the present invention is an ethylene-propylene-non-conjugated diene copolymer rubber obtained by a known method, and carbon is used as a diene monomer. Non-conjugated dienes having 5 to 20 atoms, such as 1,4-pentadiene, 1,4- and 1,5-hexadiene, 2,
5-Dimethyl-1,5-hexadiene and 1,4-octadiene, etc., Cyclic dienes such as 1,4-cyclohexadiene, cyclooctadiene, dicyclopentadiene, alkenylnorbornenes such as 5-ethylidene- and 5-butylidene-2-norbornene , 2-methallyl, 2-isopropenyl-5-norbornene, and the like. Among these, those using ethylidene norbornene or dicyclopentadiene are preferable. These EPDM are ethylene / propylene 40 /
The copolymer is preferably copolymerized in a weight ratio of 60 to 92/8, preferably 45/55 to 80/20, and when the above diene monomer is copolymerized, the iodine value is 40 or less, preferably 30. It is desirable to be present in an amount such that The preferred embodiments can be discussed in the same manner as detailed above for EPM.

The above rubber component (ie EPM, EPD)
M or a mixture thereof) can be substantially amorphous, but can also partially contain crystals. These crystal components are possible even if the peak value of the melting point determined by DSC measurement is 100 ° C. or higher.
It is also possible to use one that is from 00 ° C. or lower to around room temperature.
The optimum value of the crystallinity of the crystal component contained in rubber cannot be generally discussed. Because it is possible to improve the strength of the thermoplastic elastomer-like composition by increasing the crystal component, but there is a risk of bleeding because the softening agent to be compounded is eliminated by the crystals in the rubber component,
It needs to be determined in consideration of the crystallinity in the rubber component, the crystal form (peak temperature of melting in DSC, etc.) and the blending amount of the softening agent.

The powdery rubber in the present invention can be obtained by a known method. Such a method is for example
JP-B-63-40804, 63-40805, JP-A-5
9-215304 and Japanese Patent Application No. 2-319196 can be referred to. It is preferable that the powdery rubber has a bulk specific gravity of 0.3 or less, a maximum value of primary particles of the powder of about 10 mm or less, and a number average value of the maximum length of 1 mm or less. More preferably, 90% or more of the total number of powder particles have a maximum length of 0.5 mm or less. In other words, the weight of 100 particles is less than 0.1 g. Generally, the powdery rubber having such properties has a rapid oil absorption rate of the softening agent per unit time when it is not melted, and therefore the resin component, the rubber component and the softening agent are directly supplied to the twin-screw extruder to crosslink. It is considered suitable for dynamic heat treatment with the agent.

The advantages of using the powdery rubber as described above are as follows. Ie essentially 2
It can be directly supplied to the axial extruder, and unlike the pelletized rubber, the step of granulation can be omitted when granulating. Further, in the process of blending the softening agent, it is substantially unnecessary to oil-extend the rubber component before mixing with the extruder to form particles (pellets) in the granulator. Unlike rubber pellets, powdered rubber has a large specific surface area (surface area / volume ratio), so it is possible to significantly shorten the residence time when blending a softening agent. It is possible to perform the kneading of rubber and resin components and the process of dynamic heat treatment in the same extruder. Also, when liquid compounds are used as the cross-linking agent and cross-linking aid , these liquid substances are selected in the rubber. It becomes possible to impregnate it. Furthermore, since the primary particle size of the resin component and the rubber component is already fine, it is possible to obtain a composition that is well dispersed.

Without using powdered rubber as a rubber component at all, for example, pelletized rubber which is not oil-extended, resin component and softening agent are directly supplied to a twin-screw extruder to dynamically use a crosslinking agent. It is also possible to produce a thermoplastic elastomer composition by heat treatment. However, in this case, the step of granulating rubber as described above is required,
Not economic. Furthermore, as a reason why it is not suitable to use pelletized rubber without using powdered rubber at all, when the amount of the softening agent relative to the rubber component is large, especially when the softening amount exceeds 50 parts by weight with respect to 100 parts by weight of the rubber component. In the case of using an agent, in a manufacturing method in which a rubber component, a resin component and a softening agent are directly supplied to a twin-screw extruder, unfavorable results such as retention and backflow of the softening agent in the twin-screw extruder may be brought about. However, it is extremely difficult to stably manufacture the composition.

Besides rubber in powder form as a rubber component, rubber or a component containing rubber which can be directly supplied to a twin-screw extruder having a shape other than powder form within a range not departing from the gist of the present invention, such as rubber. It is also possible to use pelletized rubber, crumb-shaped rubber, pellet-shaped rubber mixed with a resin component and / or a softening agent, crumb-shaped rubber or a mixture thereof with powdered rubber. When these components having a shape other than powder are used in combination with rubber or a component containing rubber, the ratio cannot be strictly specified, but when the blending ratio of the softening agent is high, a shape other than powder is used. It is preferable to reduce the amount of rubber contained. This is because an increase in rubber components having poor oil absorption properties, such as rubber pellets, may cause unfavorable results such as backflow of the softening agent in the twin-screw extruder. This is because, since the granulation process has been performed, the economic effect thereof is reduced as compared with the case where powder rubber is used.

Among the components (b), examples of polyolefin resins include the following. That is, it includes a crystalline, high molecular weight solid product obtained from the polymerization of one or more monoolefins by either high pressure, medium pressure or low pressure processes. Examples of satisfactory olefins are ethylene, propylene, 1-
Butene, 1-pentene, 1-hexene, 2-methyl-1
-Propene, 3-methyl-1-pentene, 4-methyl-
Homopolymers and copolymers of 1-pentene and 5-methyl-1-hexene and mixtures thereof, preferably polypropylene resins. The polypropylene-based resin is isotactic homopolypropylene or a random or block copolymer of α-olefin such as ethylene, butene-1, hexene-1 and propylene, and the crystal component of which is polypropylene.

The polyolefin resin component contributes to the improvement of heat resistance, mechanical strength and fluidity of the thermoplastic elastomer, and for this purpose, the melting point (maximum melting peak temperature) measured by DSC is The presence of at least one at 155 ° C. or higher is preferable. The melt flow index (MFI) at 230 ° C is 0.01 to 100 g /
It is 10 minutes, preferably 0.1 to 20 g / 10 minutes.

Among the components (b), the modified polyolefin resin is a product obtained by modifying the above-mentioned polyolefin resin with a polar monomer, and is used for improving the adhesiveness and paintability of the polyolefin. It is what is done. As the polar monomer, α, β unsaturated carboxylic acid or its derivative is preferably used.

Examples of these polar monomers include α, β unsaturated carboxylic acids such as acrylic acid and methacrylic acid,
Maleic acid, fumaric acid, itaconic acid, citraconic acid,
Tetrahydrophthalic acid, bicyclo [2,2,1] hept-2-
Unsaturated dicarboxylic acids such as ene-5,6-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrohydrophthalic anhydride, bicyclo [2,2,1] hept-2
Unsaturated dicarboxylic acid anhydrides such as -ene 5,6-dicarboxylic acid anhydride, vinyl acetate, methyl (meth) acrylate,
Ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth)
Octyl acrylate, lauryl (meth) acrylate,
Benzyl (meth) acrylate, glycidyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, polypropylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, (meth) acrylic Acid polyethylene glycol polypropylene glycol, (meth) acrylic acid polyethylene glycol polytetramethylene glycol, (meth) acrylic acid methoxy polyethylene glycol, methacrylic acid glycerol, methyl fumarate, ethyl fumarate, propyl fumarate, butyl fumarate, Dimethyl fumarate, diethyl fumarate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, dibutyl fumarate, methyl maleate, ethyl maleate, isop maleate Unsaturated carboxylic acid esters such as pill, s-butyl maleate, tert-butyl maleate, lauryl maleate, stearyl maleate, cyclohexyl maleate, dimethyl maleate, diethyl maleate, dipropyl maleate, dibutyl maleate. Examples include unsaturated carboxylic acid amides such as maleic acid monoanilide, maleic acid monobenzylamide, N-hydroxymethyl (meth) acrylamide, N, N'-di (hydroxymethyl) (meth) acrylamide, and N-hydroxyethylmaleimide. can do.

The size of the component (b) does not have to be the same as that of the powdery rubber, but it must be such that it can be directly supplied to at least a twin-screw extruder. , Beads or pellets are preferred. Generally these preferred sizes are such that the maximum maximum length of the particles is 20 mm or less, preferably 10 mm or less and the average weight per particle is about 0.1 g or less.

The powdery polyolefin resin is prepared by the vapor phase method,
It can be directly obtained by a known polymerization technique such as a slurry method or a solution method. As the bead-shaped polyolefin resin, for example, a commercially available product under the trade name of Valtec by Himont Co. is available. The pellet-shaped resin can be produced by a known method which is already generally used industrially.

The powdered modified polyolefin-based resin can be obtained by modifying the powdery polyolefin-based resin while maintaining the powder shape, and it is possible to use a known method. is there. For example, as such a method, Japanese Examined Patent Publication (Kokoku) No. 55-32722 and Japanese Patent Laid-Open No. Sho 50-77
493, 62-4050, 64-87611, JP-A-1
-108207 can be illustrated. Further, the modified polyolefin resin in the form of pellets can be obtained by modifying the polyolefin resin by a known method, for example, suspension, melting, or modifying the modified polyolefin resin obtained by modifying the solution with a granulator. Alternatively, it can be manufactured by performing modification and granulation in a batch process in a molten state.

Component (c) is added to improve the fluidity and flexibility of the thermoplastic elastomer of the present invention, and includes paraffin-based, naphthene-based, aromatic-based and polybutene-based softening agents. Can be used. In the present invention, paraffin type, naphthene type and polybutene type are particularly preferable.

The addition amount varies depending on the properties of the desired thermoplastic elastomer, the physical properties of the component (a) and the component (b), the mixing ratio thereof, etc., but is 5 to 200 per 100 parts by weight of the component (a). Parts by weight, preferably 30 to 100 parts by weight. If the amount is less than 5 parts by weight, the thermoplastic elastomer has almost no improvement effect.
This is because the amount of 00 parts by weight or more cannot be smoothly supplied by a method in which a twin-screw extruder is used and the components (a) and (b) are directly supplied from a supply port different from the supply port.

As the crosslinking agent, a known crosslinking agent capable of crosslinking can be used. For example, sulfur, (alkyl) phenol resin, halogenated (alkyl) phenol resin,
Quinone dioxime, bismaleimide type, JP-A-61-1
The halogenated melamine or organic peroxide disclosed in 20841 can be used. If necessary, they can be used together.

With these cross-linking agents, a cross-linking accelerator can be used depending on the cross-linking system. For details of these, known literatures such as the literature cited in the present invention, "Cross-linking Agent Handbook" (1981, Published by Taiseisha, edited by Zenzo Yamashita and Tosuke Kaneko).

As the organic peroxide used here,
For example, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (ter
t-butylperoxy) hexane, 1,3-bis- (t
ert-butylperoxy-isopropyl) -benzene, tert-butylcumyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy)
-Hexyne, 3,1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane, ter
Examples thereof include t-butyl peroxybenzoate and tert-butyl peroxyisopropyl carbonate.

Further, it is possible to use a crosslinking aid together with these crosslinking agents, if necessary. Examples of the crosslinking aid used here include sulfur, p-quinonedioxime,
p, p'-dibenzoylquinone dioxime, ethylene glycol dimethacrylate, pentaerythritol triacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane trimethacrylate,
Triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, diallyl terephthalate, polyethylene glycol dimethacrylate, 1,2-polybutadiene, N, N'-m-phenylene bismaleimide, maleic anhydride, neopentyl glycol diacrylate, glycidyl methacrylate. Can be mentioned.

Compositions suitable for practicing the present invention may include components other than component (a), component (b), softener, crosslinker. The shape and state of the components other than these essential components are not particularly limited, but when they are directly supplied to the twin-screw extruder, they need to be liquid, powdery, or in the form of small particles.
If it is in the form of a body or a blob, the maximum length is 20 mm.
Or less, preferably 10 mm or less, more preferably 5 mm or less, still more preferably 1 mm or less.

As additives that can be added, for example, inorganic fillers such as talc, carbon black, mica, silica, calcium carbonate, barium sulfate, calcium silicate, and aluminum silicate can be added. Further, if necessary, antioxidants, ultraviolet absorbers, stabilizers such as metal deterioration inhibitors, lubricants, antistatic agents, electrical property improvers, flame retardants, processability improvers, pigments and other resins, rubbers. Ingredients that are commonly ordinarily added can be added.

These components (a) and (b) are used in a process before being directly supplied to the twin-screw extruder, using a cross-linking agent and, if necessary, additives and fillers and a mixer such as a Henschel mixer. Can be mixed together, or the rubber component, resin component and other components can be directly fed to the feed port of the twin-screw extruder using two or more feeding devices.

In the former case, when the sizes of the component (a) and the component (b) are greatly different, a small amount of a viscous liquid such as a softening agent is added in advance in order to avoid segregation in the feeding device to improve the miscibility. It is also possible to improve it. However, if such a viscous liquid is also used in a large amount, blocking or bridging will occur in the feeder, resulting in poor supply or inability to supply, so extreme use must be avoided. Also in the latter case, it is desirable that the supply port is set at a position that prolongs the residence time in the extruder in order to improve the mixing of the rubber component and the resin component.

Although a part of the softening agent can be supplied from the same supply port as the resin and the rubber as described above, it is difficult to cause blocking or bridging when it is desired to add a large amount of the softening agent.

According to the present invention, when it is desired to add a large amount of the softening agent, for example, a large amount of the softening agent of 20 parts by weight or more to 100 parts by weight of the component (a), particularly 100 parts of the component (a). When 100 parts by weight or more of the softening agent is blended in one step with respect to parts by weight, the softening agent can be stably supplied by supplying the softening agent from a supply port different from the resin and rubber supply ports. Shown to be valid. The other supply port here is, for example, at least a liquid supply port provided on the die side of the twin-screw extruder with respect to the supply ports to which the components (a) and (b) are supplied.

The position of the preferable softener supply port cannot be strictly defined because it varies depending on the composition of the components (a) and (b), but it should be close to the supply ports of the components (a) and (b). Is. This is because the rubber and the softening agent can be sufficiently kneaded in this way.

However, it should be noted that if the resin and rubber supply ports are extremely close to each other, blocking easily occurs near the resin and rubber supply ports. Further, more preferably, at least one supply port is provided between the supply port for the rubber component and at least the region where the rubber component is plasticized. When the rubber component and the resin component are completely melted, another effort is required to obtain a composition to which a large amount of softening agent is stably supplied. Therefore, the softener supply port can be formed by directly forming a hole in the barrel of the twin-screw extruder, using a liquid-only supply plate (so-called liquid addition plate), or using a vent port. In kneading using a twin-screw extruder, the component (a)
It is necessary that the crosslinking reaction of the rubber be substantially completed within the residence time of the component (b).

The temperature of the dynamic heat treatment is a temperature sufficient to soften the resin component comprising at least one of the polyolefin resin and the modified polyolefin resin as the component (b), or, if the resin is crystalline, above its melting point. Temperature, which is generally in the temperature range of 160 ° C to 300 ° C.

The kneading conditions of the twin-screw extruder can be changed according to the composition of the component (a), the component (b), the softening agent, etc., and the required properties of the final product. Although it cannot be said, for example, in the dynamic crosslinking using an organic peroxide, it is possible to refer to the conditions described in JP-A-58-25340. Further, in the dynamic cross-linking in a system using a cross-linking agent other than organic peroxide, for example, JP-A-59-5804.
It is also possible to refer to the condition of 3. Further, the cross-linking agent, catalyst, accelerator and the like necessary for cross-linking can be supplied together with the rubber component and the resin component, or so-called side-feeding can be performed from a supply port different from these. In the latter case, it is effective to carry out after the resin component and the rubber component are melt-kneaded.

The twin-screw extruder used in the present invention is an extruder with the same or different directions. Specific examples of such an extruder include a commercially available Warner extruder (manufactured by Warner, West Germany), a TEX90 extruder (manufactured by Japan Steel Works), BT.
80 extruder (manufactured by Hitachi, Ltd.), TEM70 extruder (manufactured by Toshiba Machine), KTX70 extruder (manufactured by Kobe Steel), PTE9
0 extruder (made by Mitsubishi Heavy Industries) can be mentioned. Hereinafter, the present invention will be described with reference to examples.

[0040]

[Example] (Measurement method) (MFI) JIS K7210 (load 2.16 kg 230 ° C) (HLMFI) JIS K7210 (load 21.6 kg 230 ° C) (tensile breaking strength, elongation) JIS K6301 (Shore A hardness) ASTM D-676 -49 (Functional group content in modified product) By infrared absorption spectroscopy. (Melting Point) After molding, the condition was adjusted to 21 ° C. for 1 week, and then the temperature was measured at a temperature rising rate of 20 ° C./min using DSC7 type manufactured by Perkin Elmer.

(Raw Material) << pdEPM-1 >> Ethylene-propylene copolymer rubber (ethylene 73.
5 % by weight, 26.5% by weight of propylene, peak of maximum melting point of DSC 110 ° C., maximum value of maximum length of particles 5.2
mm, same number average value 0.5 mm, number of particles 0.5 mm or less 99%, bulk specific gravity 0.252, MFI 0.0
3 g / 10 min) << pdEPM-2 >> Ethylene-propylene copolymer rubber (51% by weight of ethylene, 49% by weight of propylene, peak of melting point of DSC 112 ° C, maximum value of maximum length of particles 1.07 m)
m, same number average value 0.30 mm, number of particles 0.5 mm or less 91%, bulk specific gravity 0.110, HLMFI
0.05 g / 10 min) << pdEPDM >> ethylene-propylene copolymer rubber (ethylene 71.
4 wt%, propylene 26.4 wt%, ethylidene norbornene 2.2 wt%, DSC maximum melting point peak
111.5 ° C, maximum particle length maximum value 4.8 mm, same number average value 0.8 mm, bulk specific gravity 0.121, HLMF
I 0.006 g / 10 min) << plEPDM >> Ethylene-propylene-ethylidene norbornene terpolymer rubber (ethylene 70.5% by weight, propylene 2
5.0% by weight, ethylidene norbornene 4.5% by weight, maximum melting point peak of DSC 43.0 ° C., maximum value of maximum particle size 5.8 mm, number average maximum length 4.4 mm,
Bulk specific gravity 0.403, average weight of particles 0.0503 g /
Mooney viscosity ML (1 + 4) 121 ° C: 65)

<< PP-1 >> Isotactic polypropylene resin (powder form with MFI 0.5 g / 10 min, melting point 160 ° C., number average particle size 0.25 mm, bulk specific gravity 0.425) << PP-2 >> containing rubber Isotactic polypropylene resin (MFI 1.5 g / 10 min, melting point 160 ° C., powder content of rubber content 20% by weight) << PP-3 >> ethylene-propylene random copolymer resin (MFI 0.1 g / 10 min, melting point 136 ℃, powder form with ethylene content of 7% by weight) << PP-4 >> isotactic polypropylene resin (MFI 0.5g / 10min, melting point 160 ° C pellet form) << modified PP >> maleic anhydride modified isotactic polypropylene resin (MFI 20 g / 10 min, melting point 160 ° C., maleic anhydride 0.1 wt% pellets

<< Softening agent >> PW380 (paraffinic softening agent, manufactured by Idemitsu Kosan Co., Ltd.) << Crosslinking agent >> Kayahexa AD (Kayakakuzo, 2,5-)
Dimethyl-2,5-di (tert-butylperoxy)
Hexane) << Crosslinking aid >> Percalink 301 (manufactured by Kayaku Nouri Co.,
Triallyl isocyanurate)

(Example 1) This was carried out using the same-direction twin-screw extruder KTX-37 manufactured by Kobe Steel, L / D = 30 and a barrel diameter of 37 mm. 32 parts by weight of the raw material PP-1 excluding the softening agent, 48 parts by weight of pdEPM-1, 0.5 parts by weight of the cross-linking agent, 0.5 parts by weight of the cross-linking aid, and the antioxidant were mixed with a Henschel mixer and then supplied. Was supplied from the hopper, and 20 parts by weight of the softening agent was supplied by a fixed amount feed using a gear pump using a liquid addition plate provided on the die side of the hopper and on the hopper side of the first kneading zone.
The rotation speed of the screw was 200 rpm, and the temperature of the barrel at this time was 200 ° C. Residence time is about 1.5
It was ~ 2.5 min. At this time, the composition could be stably obtained. The results are shown in Table 1.

(Examples 2 to 8 and 12) The rotation number of the screw, the resin, the rubber type, the composition, and the temperature setting of the barrel were appropriately changed. The other supply methods are the same as those in the first embodiment. The results are shown in Table 1.

Example 9 A composition was obtained in the same manner as in Example 1 except that powdered rubber (pdEPDM) was used in combination with the powdered rubber. The results are shown in Table 1.

Example 10 Veiled EPDM (ethylene-propylene-ethylidene norbornene terpolymer rubber: ethylene 59% by weight, propylene 33% by weight, ethylidene norbornene 8% by weight, Mooney viscosity ML (1 + 4) 100 ° C. 65 ) Is 21 parts by weight, PP-
21 parts by weight of 1, a softening agent of 15 parts by weight, and a crosslinking aid of 0.8 parts by weight were kneaded with a Banbury mixer to obtain pellets (MP-1). After mixing 37 parts by weight of MP-1, 23 parts by weight of pdEPM-1, 0.7 parts by weight of a cross-linking agent and an antioxidant with a Henschel mixer, the supply is performed from a hopper, and the softening agent is supplied from the hopper to the die side. Then, it was supplied by a constant amount feed using a liquid addition plate provided on the hopper side from the first kneading zone (20 parts by weight). The screw speed is 25
It is 0 rpm, and the temperature setting of the barrel at this time is 160
° C. The residence time was about 1.5 to 2.5 min. At this time, the composition could be stably obtained.

Example 11 Modified PP was used as a part of the resin component. A composition was obtained in the same manner as in Example 1 except that the composition was partially changed. The results are shown in Table 1.

[0049]

[Table 1]

(Comparative Example 1) This was carried out using the same-direction twin-screw extruder KTX-37 manufactured by Kobe Steel, L / D = 30 and a barrel diameter of 37 mm. Raw materials excluding softener, plEPDM (pellet form) 44 parts by weight, PP-4 22.5 parts by weight (E
Avoid classification as PDM is pellet. ), A crosslinking agent 0.
After mixing 5 parts by weight, 0.5 parts by weight of a crosslinking aid, and an antioxidant with a Henschel mixer, the supply is carried out from a hopper, and the softening agent is supplied from the hopper to the die side of the first kneading zone. Using a liquid addition plate
It was supplied by quantitative feed using a gear pump (3
3.5 parts by weight). The rotation speed of the screw was 240 rpm, and the temperature setting of the barrel at this time was 160 ° C. The residence time was about 1.5 to 2.5 min. In this case, the softening agent stayed in the barrel and the desired composition could not be obtained.

(Comparative Example 2) The softener supply port was made of a resin component,
Example 1 is the same as Example 1 except that the process was performed from the same place as the rubber component supply port. In this case, the softening agent, the resin component, and the rubber component adhered to each other near the supply port and stagnated, after which the raw material could not be supplied.

(Comparative Example 3) pdEPM-1 11 parts by weight, plEPDM 33 parts by weight, PP-1 10 parts by weight, PP-3 11 parts by weight, crosslinking agent 0.7 parts by weight, crosslinking aid 0.8 parts by weight. Was mixed with a Henschel mixer, and then supplied from a hopper, and 35 parts by weight of the softening agent was supplied by a gear pump using a liquid addition plate provided on the hopper side from the first kneading zone on the die side. The composition could not be obtained stably. When the kneading conditions of the screw were changed to mild conditions, backflow of the softening agent was avoided, but the resulting composition was visually non-uniform.

[0053]

INDUSTRIAL APPLICABILITY According to the present invention, a rubber-crosslinked thermoplastic elastomer composition containing a softening agent can be economically and stably manufactured with a small number of manufacturing steps. The thermoplastic elastomeric composition thus obtained has excellent balance of flexibility, rubberiness, and strength, and has good fluidity, so that automobile parts such as bumpers, corner bumpers, side moldings, spoilers, etc. Light electrical parts such as hoses, various packings,
Suitable for materials such as insulating sheets, electric wires and cables, for example flexible cords, booster cables, civil engineering / construction materials, for example, waterproof sheets, waterproof materials, etc., and these parts are usually blow molded, extruded, injection molded, etc. It can be easily molded by the molding method.

Claims (4)

(57) [Claims] 1. (a) A bulk specific gravity of 0.3 or less and a maximum length of
Maximum value is 10 mm or less, number average value of maximum length is 1 mm or less
Powdery ethylene is - propylene copolymer rubber if
Kuwae styrene - propylene - non-conjugated diene copolymer rubber or mixtures thereof 20-80 parts by weight, (b) polyolefin-based resin, modified polyolefin resin, or a mixture 80 to 20 parts by weight (c) softener thereof 5 to 100 parts by weight of component (a)
Of 200 parts by weight of the three components, the component (c) was directly supplied to the twin-screw extruder from a supply port different from the component (a) and the component (b) were directly supplied, and the crosslinking agent was used. A process for producing a thermoplastic elastomer-like composition, characterized in that the component (a) is crosslinked by dynamically heat-treating in the twin-screw extruder. 2. A supply port of the component (c) is, component (a) Oyo
Preparation of a thermoplastic elastomeric composition 請 Motomeko 1 wherein that provided at least one between the supply port and the area where they are plasticizing fine component (b). 3. Component (a) is 90% of the total number of powder particles.
The above is powder particles having a maximum length of 0.5 mm or less.
A method for producing the thermoplastic elastomeric composition described . 4. The blending amount of the component (c) is 100 for the component (a).
Preparation of 30 to 200 parts by weight of Der Ru請 Motomeko 1 wherein <br/> thermoplastic elastomeric composition by weight parts.