JPH0733916A - Thermoplastic elastomer composition - Google Patents

Abstract

PURPOSE:To provide the title composition which can be molded with an appara tus usually used for molding a thermoplastic resin, has excellent rubbery proper ties because its olefin copolymer rubber part is crosslinked, has excellent moldability because its flow is good, and can give a high-strength product. CONSTITUTION:The composition is one prepared by partially crosslinking a mixture comprising 5-85 pts.wt. peroxide-crosslinkable olefin copolymer rubber (a), 10-50 pts.wt. peroxide-decomposable olefin plastic (b) and 5-55 pts.wt. [(a)+(b)+(c)=100 pts.wt.] peroxide-crosslinkable olefin plastic (c) by subjecting it to a dynamic heat treatment in the presence of 0.1-20 pts.wt. bismaleimide compound and 0.01-5 pts.wt. organic peroxide, wherein immediately after component (b) is subjected to a degradation treatment, components (a), (c), (d) and (e) are added to treated component (b), and the entire mixture is subjected to a dynamic heat treatment to effect the partial crosslinking, or one wherein the entire mixture is subjected to a dynamic heat treatment to effect the partial crosslinking, and a mineral oil softener is added to the formed composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer composition, and more specifically, a peroxide-crosslinkable olefin copolymer rubber, a peroxide-decomposable olefin plastic, a peroxide-crosslinkable olefin plastic, Dynamically heat-treated and partially crosslinked a composition consisting of a maleimide compound, an organic peroxide and, if necessary, a mineral oil-based softener, a crosslinking aid, automobile interior / exterior parts, civil engineering and construction related materials, industrial machine parts, medical treatment The present invention relates to a thermoplastic elastomer composition that can be extrusion-molded or injection-molded into related equipment, housings, OA parts, sundries and the like.

[0002]

2. Description of the Related Art In order to injection-mold ordinary rubber, a special molding machine is required because a vulcanization step is required after compounding and kneading additives into the rubber and molding in a mold. There is a problem that the time is long and the process is complicated, and there is a similar problem in extrusion molding, which has been an obstacle to mass production of rubber products. Therefore, there has been a strong demand for a thermoplastic elastomer composition which can be molded without requiring a vulcanization step and has a rubber-like performance. A composition comprising a curing agent such as a peroxide-crosslinking olefin-based copolymer rubber, a peroxide-decomposing olefin-based plastic, a peroxide-crosslinking-type olefin-based plastic, and an organic peroxide is thermally treated in a molten state to form an olefin. A composition comprising a resin and a partially crosslinked rubber is already known as an olefinic thermoplastic elastomer composition, as described in, for example, Japanese Patent Publication No. 5-6577.

However, the thermoplastic elastomer composition contains an organic peroxide-decomposing olefin plastic, an organic peroxide cross-linking olefin copolymer rubber, and a peroxide cross-linking olefin plastic at approximately the same time in a continuous or batch-type kneading. It is manufactured by heat treatment in the presence of an organic peroxide and has excellent performance as a thermoplastic elastomer, but its fluidity is significantly inferior to that of general-purpose plastics, and extrusion molding In the case of injection molding, there is a drawback that remarkable flow marks are generated and a product having a good appearance cannot be obtained. In order to improve the fluidity of the thermoplastic elastomer composition and the thin-film formability during sheet molding, (a) increase the melt flow ratio (MFR) of the olefinic plastic used, (b) thermoplastic elastomer composition Reduce the degree of crosslinking of the rubber part of the object,
In the method (a), the strength of the olefin-based plastic decreases due to the decrease in the molecular weight of the olefin-based plastic used, and the adhesive force between the olefin-based plastic and the rubber decreases, so that the thermoplastic elastomer is There is a problem that the strength of the composition decreases,
The method (b) has a problem that the strength of the thermoplastic elastomer composition is lowered when the degree of crosslinking of the rubber portion is lowered.

In order to improve fluidity without substantially impairing the heat resistance, tensile properties, flexibility and impact resilience of the thermoplastic elastomer composition, a mineral oil-based softening agent is added to these thermoplastic elastomer compositions. It is also known to add an agent and then dynamically heat-treat it in the presence of an organic peroxide, as described, for example, in Japanese Patent Publication No. 56-15741. Furthermore, oil-extended olefin copolymer rubber,
A thermoplastic elastomer composition obtained by dynamically heat-treating a mixture of an olefin-based plastic and a bismaleimide compound in the presence of an organic peroxide is also disclosed in, for example, Japanese Patent Application Laid-Open No. HEI-2.
No. 28232 is known.

[0005]

SUMMARY OF THE INVENTION By the way, the present inventors, when producing a thermoplastic elastomer composition,
As a result of studying peroxide-decomposable olefin-based plastics, a thermoplastic elastomer composition was subjected to degradation treatment in which it was decomposed in the presence of organic peroxide or under heat and shearing force, and immediately thereafter, peroxide-crosslinkable olefin-based plastics were used. When a polymer rubber is added and a cross-linking reaction is performed in the presence of a bismaleimide compound and an organic peroxide, an olefin-based plastic and an olefin-based copolymer rubber, which have been decomposed in advance and whose MFR has been increased to the same degree, are added simultaneously. It was found that the tensile strength was improved as compared with the thermoplastic elastomer composition crosslinked in the presence of organic peroxide, and the invention was completed and a patent application was filed separately.

Further, as a result of examining the timing of addition of the mineral oil-based softening agent when producing the thermoplastic elastomer composition, the present inventors have found that the mineral oil-based softening agent is a peroxide-crosslinking olefin-based copolymer rubber and a peroxide. In the process of dissolving in a resin composed of oxide-decomposable olefin plastics, a large viscosity unevenness occurs in the resin (the portion where the mineral oil-based softening agent is dissolved has a low viscosity, and the other is high viscosity), and the mineral oil-based softening agent dissolves in the resin. When the cross-linking reaction is performed in the process, the high-viscosity portion is not kneaded (the high-viscosity portion is difficult to be kneaded) and cross-linking is performed, which causes coarse particles of the cross-linked rubber to occur, and the coarse particles of the cross-linked rubber are generated. Was found to be a fish eye when a thermoplastic elastomer is processed into a sheet, which adversely affects the appearance, physical properties, and secondary workability of the product. Separately patent application in La.

The present inventors have developed a peroxide-decomposable olefin-based plastic in the presence of organic peroxide.
Alternatively, when degradation treatment is carried out to decompose under heat and shearing force, a large number of radicals are present in the peroxide-decomposing olefin plastic, and the peroxide cross-linking olefin copolymer rubber is added to the olefin plastic. When the cross-linking reaction is performed in the presence of organic peroxide, the adhesive property at the interface between the peroxide-decomposing olefin-based plastic and the peroxide cross-linking olefin-based copolymer rubber is improved, which improves the tensile strength. Is estimated. Further, it was found that the thermoplastic elastomer composition thus obtained has a large MFR of the entire composition and not only improves the fluidity but also the tensile strength.

Further, the present inventors have described a method for producing the above-mentioned thermoplastic elastomer composition, in particular, peroxide cross-linking olefin copolymer rubber, peroxide decomposing olefin plastic, peroxide cross-linking olefin plastic, By applying a mixture consisting of organic peroxide and bismaleimide compound to a thermoplastic elastomer composition subjected to a dynamic heat treatment, high strength due to good cross-linking, low hardness due to high filling of mineral oil-based softening agent, flame resistance, blocking resistance It was found that a thermoplastic elastomer composition having good workability and improved mechanical strength and fluidity can be obtained, and the present invention was completed.

[0009]

The first invention of the present application is
(A) 5 to 85 parts by weight of peroxide cross-linking olefin copolymer rubber, (b) 10 to 50 parts by weight of peroxide decomposing olefin plastic, (c) 5 to 55 parts by weight of peroxide cross-linking olefin plastic. [Wherein (a) + (b) + (c) = 100 parts by weight] a mixture of (d) bismaleimide compound 0.1 to 20 parts by weight and (e) organic peroxide 0.01 to 5 parts by weight. In a thermoplastic elastomer composition that has been subjected to a dynamic heat treatment in the presence of a partially crosslinked thermoplastic elastomer composition, (a), (c), (d) and (e) are added immediately after the degradation treatment of (b) in advance. A thermoplastic elastomer composition characterized by being heat-treated and partially cross-linked. The second invention also relates to (a) 5 to 85 parts by weight of a peroxide cross-linking olefin-based copolymer rubber. , (B) 10 to 50 parts by weight of peroxide-decomposing olefin-based plastic, (c) 5 to 55 parts by weight of peroxide-crosslinking olefin-based plastic [however, (a) + (b) + (c) = 100 parts by weight] (D) bismaleimide compound 0.1-2
0 part by weight and (e) 0.01-5 parts by weight of an organic peroxide, in a thermoplastic elastomer composition that has been dynamically heat-treated and partially crosslinked, immediately after (a) is pre-degraded (a) ), (C), (d) and (e) are added thereto to carry out a dynamic heat treatment to terminate the partial crosslinking reaction, and then (f) a mineral oil-based softening agent is added. ,.

The (a) peroxide-crosslinking olefin copolymer rubber used in the present invention is an amorphous random elastic copolymer containing olefin as a main component and is mixed with an organic peroxide and heated. A rubber which is crosslinked by being kneaded below to have reduced fluidity or which does not flow, for example, a rubber such as ethylene-propylene copolymer rubber, ethylene-propylene-non-conjugated diene rubber, ethylene-butadiene copolymer rubber. Of these, ethylene-propylene copolymer rubber and ethylene-propylene-non-conjugated diene rubber are preferable, and as the ethylene-propylene-non-conjugated diene copolymer rubber, as the diene monomer, those having 5 to 20 carbon atoms are preferable. Conjugated dienes such as 1,4-pentadiene, 1,4- and 1,5-hexadiene, 2, -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- and 2-isopropenyl-5-
Examples thereof include those using norbornene, and among these, ethylene-propylene-ethylidene norbornene copolymer rubber is particularly preferable in that a composition excellent in heat resistance, tensile properties and impact resilience can be obtained.

In the present invention, the addition amount of the (a) peroxide cross-linking olefin-based copolymer rubber is from 5 to 5.
It is in the range of 85 parts by weight, preferably in the range of 30 to 70 parts by weight, and if it is less than 5 parts by weight, the flexibility and impact resilience of the composition will be impaired, resulting in sink marks in the product.
If it exceeds 5 parts by weight, the heat resistance and fluidity of the composition will be impaired.

The (b) peroxide-decomposable olefin-based plastic used in the present invention is a crystalline part which is degraded in the presence of organic peroxide or under heat and shearing force to increase the fluidity of the resin. An olefin-based plastic containing, for example, a crystalline high molecular weight solid product obtained by the polymerization of one or more mono-olefins, examples of preferred olefin polymers include propylene, 1-butene, 1-pentene, 1
-Hexene, 2-methyl-1-propene, 3-methyl-
Homopolymers, copolymers of 1-pentene, 4-methyl-1-pentene, 5-methyl-1-hexene and mixtures thereof, and particularly preferably polypropylene resins. The polypropylene-based resin is isotactic polypropylene or a random or block copolymer of propylene and an α-olefin such as ethylene, butene-1, hexene-1, and a copolymer having a crystal portion of polypropylene.

In the present invention, the peroxide-decomposable olefin-based plastic needs to be adjusted to have a melt flow rate of 50 to 10000 g / 10 minutes by degradation treatment. As the method of degradation, decomposition treatment is carried out in the presence of organic peroxide or by heat and shearing force. In the case of degrading with organic peroxide, it may be carried out by melt-kneading at 170 to 250 ° C. for 0.5 to 5 minutes in the presence of organic peroxide. The amount of the organic peroxide used is 2 parts by weight or less based on 100 parts by weight of the peroxide-decomposable olefin-based plastic, and can be appropriately changed and used depending on the target melt flow rate.

Decomposition of peroxide-decomposable olefinic plastics under heat and shear in the present invention means
Peroxide decomposition type olefin plastic 29
A time sufficient to decompose in the range 0-480 ° C, preferably 320-450 ° C, typically 1-10 minutes,
Preferably, the mixture is kneaded for 2 to 6 minutes to be decomposed. In the present invention, the peroxide-decomposable olefin-based plastic contributes to the improvement of the fluidity and heat resistance of the composition, and the amount of the peroxide-decomposable olefin-based plastic is 10 to 100 parts by weight of the total composition. It is in the range of 50 parts by weight, preferably 15 to 50 parts by weight, and when it exceeds 50 parts by weight, flexibility and impact resilience of the composition are impaired and a sink mark is produced in the product. If the amount of the olefin-based plastic is less than 10 parts by weight, the heat resistance and fluidity of the composition will be impaired and the object of the present invention will not be achieved.

The (c) peroxide-crosslinking olefin-based plastic used in the present invention is a plastic containing olefin as a main component, and is mixed with an organic peroxide, and is kneaded under heating to crosslink and flow. Of a polyethylene having a density in the range of 0.910 to 0.940 g / cm ³ , a low density polyethylene (LDPE), ethylene and an α-olefin having 4 to 8 carbon atoms. Copolymers can be used. This copolymer also includes linear low density polyethylene (LLDPE).

In this copolymer, the α-olefin having 4 to 10 carbon atoms which is copolymerized with ethylene is 1-
Butene, 1-pentene, 1-hexene, 4-methyl-1
-Pentene, 1-octene, 1-decene, or a mixture of at least two of these. Further, this copolymer is a copolymer having an ethylene content of 90 to 99.5 mol%, preferably 94 to 99 mol%, and a dynamic heat treatment when the ethylene content is less than 90 mol%. Afterwards, "stickiness" occurs, impairing heat resistance, and 99.5 mol%
If it exceeds the range, the flexibility of the thermoplastic elastomer obtained is reduced, so that both are not preferable. Further, the copolymer has a crystallinity of 40 to 70% measured by an X-ray diffraction method.
The thing of what is used is suitable. In addition, the melt index (19
0 ° C., 2.16 Kg load) is 0.1 to 50 g / 10 minutes,
The one having 0.2 to 30 g / 10 minutes is preferably used.

In the present invention, the peroxide-crosslinking olefin-based plastic contributes to the improvement of the strength of the composition, the improvement of the fluidity, and the improvement of the molding processability, and the peroxide-crosslinking type olefin plastic per 100 parts by weight of the total amount of the composition. The amount of olefinic plastic is 5 to 55 parts by weight, preferably 1
The amount is in the range of 0 to 50 parts by weight, and when it exceeds 55 parts by weight, the flexibility and impact resilience of the composition are impaired and the product is sinked. On the other hand, the peroxide cross-linking olefin-based plastic is 5 parts by weight. When it is less than the part, the strength, fluidity and molding processability of the composition are impaired and the object of the present invention cannot be achieved. The (f) mineral oil-based softening agent used in the present invention usually weakens the intermolecular action force of the rubber during roll processing of the rubber, facilitates the processing, and assists the dispersion of carbon black, white carbon, etc. , A high-boiling petroleum fraction compounded to improve the fluidity and flexibility of thermoplastic elastomers, such as paraffin-based, naphthene-based,
Aromatic softeners can be used, especially paraffinic,
Teften type is preferable.

The blending amount of the mineral oil type softener in the present invention is
Total amount of peroxide-crosslinking olefin copolymer rubber and peroxide-decomposing olefin plastic 1
5 to 300 parts by weight, preferably 10 to 100 parts by weight
It is 200 parts by weight, particularly 10 to 100 parts by weight. If the amount is less than 5 parts by weight, the thermoplastic elastomer composition does not have a sufficient fluidity improving effect, and if it exceeds 300 parts by weight, the composition is The heat resistance of No. 1 is lowered, and the softening agent is exuded to impair the appearance.

The mineral oil-based softening agent may be present before the dynamic heat treatment, but it is preferably added after the dynamic heat treatment to complete the crosslinking reaction and melt-kneaded. Examples of the (d) bismaleimide compound in the present invention include N, N′-
There are m-phenylene bismaleimide, toluylene bismaleimide and the like, and by using these, blocking resistance, flame retardancy, and mechanical properties can be improved, and the compounding amount of the compound is A range of 0.1 to 20 parts by weight, particularly 0.5 to 10 parts by weight is preferable with respect to 100 parts by weight. When the compounding amount is less than 0.1, physical properties such as tensile strength are not improved and 20 parts by weight is added. If it exceeds, the tensile elongation will decrease.

The organic peroxide (e) used in the present invention for crosslinking the peroxide-crosslinking olefin-based copolymer rubber and the peroxide-crosslinking olefin-based plastic or for decomposing the peroxide-decomposing olefin-based plastic is (e) For example, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-
2,5-di- (t-butylperoxy) hexane, 2,
5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-bis (t-butylperoxy) -3,3,5 -Trimethylcyclohexane, n-
Butyl-4,4-bis (t-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide , T-butylcumyl peroxide, and the like, and of these, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane and 2,5-dimethyl-2,5-di (t -Butylperoxy) hexyne-3,1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane and n-butyl-4,4 -Bis (t-butylperoxy) vale Over door is preferable, 2,
Most preferred is 5-dimethyl-2,5-di (t-butylperoxy) hexyne-3.

When the peroxide-crosslinking olefin-based copolymer rubber and the peroxide-crosslinking olefin-based plastic are subjected to a crosslinking reaction, preferably 0.01 to 5 parts by weight, and more preferably 0.005 parts by weight, based on 100 parts by weight of the total amount of the resin.
It should be selected so as to be in the range of 05 to 2 parts by weight. When the compounding amount is less than 0.01 parts by weight, the crosslinking degree of the peroxide-crosslinking olefin copolymer rubber and the peroxide-crosslinking olefin plastic is small. As a result, the rubber properties such as heat resistance, tensile properties, elastic recovery and impact resilience of the composition are not sufficient, while when it exceeds 5 parts by weight, the crosslinking degree of the peroxide-crosslinking olefin copolymer rubber is increased. As a result, the fluidity of the entire composition decreases.

In the present invention, a bismaleimide compound and an organic peroxide crosslinking agent thereof may optionally be used together with a crosslinking aid at the time of thermal treatment. As the crosslinking aid used in the present invention, There are peroxide cross-linked, polyfunctional (meth) acrylate monomers, polyfunctional vinyls and metal salts of α, β-unsaturated carboxylic acids such as sulfur, p-quinone oxime, p, p ′.
-Dibenzoylquinone dioxime, N-methyl-N, 4
An organic peroxide crosslinking aid such as dinitrosoaniline, nitrobenzene, vinyl butyrate, vinyl stearate, zinc acrylate, zinc methacrylate, diphenylguanidine or, for example, divinylbenzene (D
VB), ethylene glycol dimethacrylate, pentaerythritol triacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane trimethacrylate (TMPT), triallyl cyanurate, triallyl isocyanurate, diallyl phthalate, diallyl terephthalate, polyethylene glycol di Methacrylate, 1,2-polybutadiene, maleic anhydride, neopentyl glycol diacrylate, and glycidyl methacrylate can be mentioned. Particularly, in the present invention, when divinylbenzene (DVB) or trimethylolpropane trimethacrylate (TMPT) is used, Peroxide cross-linking olefin copolymer rubber, which is the main component of the object to be treated, peroxide decomposition olefin plastic Fine compatibility with the peroxide-crosslinkable olefin plastics is good, and has an organic peroxide solubilizing action, to serve as a dispersing aid peroxide, a homogeneous crosslinking effect by heat treatment,
Most preferred is a composition having a well-balanced flowability and physical properties.

The amount of the crosslinking aid compounded is preferably 0.05 to 2 parts by weight, more preferably 0.1 to 1 part by weight, based on 100 parts by weight of the resin component. When the amount of peroxide is large, the cross-linking reaction proceeds, resulting in poor fluidity of the composition.On the other hand, when the amount of organic peroxide is small, it is present in the composition as an unreacted monomer. Excessive blending should be avoided because the physical history may change due to heat history during processing and molding. In the present invention, in order to accelerate the decomposition of organic peroxides, tertiary amines such as triethylamine and tributylamine, and naphthenates such as aluminum, cobalt, vanadium, copper, calcium, zirconium, manganese, magnesium, lead and mercury. It is also possible to use a decomposition accelerator such as an organic metal carboxylate such as an octanoate.

In the thermoplastic elastomer composition of the present invention, the above-mentioned peroxide-decomposable olefin-based plastic of each component is decomposed in advance in the presence of organic peroxide, or under heat and shearing force to obtain a molten state. A residual cross-linking reaction is performed by dynamically adding a residual component to the resin to carry out a partial cross-linking reaction, or a component excluding the mineral oil-based softening agent from the residual component is added to terminate the partial cross-linking reaction, and thereafter, a mineral oil is added. A system softener is added and kneaded and dissolved.
As the kneading device, a conventionally known one such as an open type mixi roll, a non-open type Banbury mixer, an extruder, a kneader, a continuous mixer or the like can be used. Among these, the non-open type device is used. Is preferred,
When carrying out the crosslinking reaction, it is preferable to carry out kneading in an inert gas atmosphere such as nitrogen or carbon dioxide.

The kneading is carried out at a temperature at which the half-life of the organic peroxide used is less than 1 minute, usually 150 to 280 ° C.
Preferably, the kneading may be carried out at 170 to 240 ° C. for 1 to 20 minutes, preferably 3 to 10 minutes. The thermoplastic elastomer composition of the present invention can be molded by an apparatus used for usual thermoplastics, is suitable for extrusion molding, calender molding, injection molding, and is also a peroxide-crosslinking olefin copolymer rubber component. Since it is partially crosslinked, it has excellent rubber-like properties such as heat resistance, weather resistance, tensile properties, flexibility and impact resilience, and has good flowability, and therefore has excellent moldability.

The thermoplastic elastomer composition of the present invention contains a filler in an amount that does not impair the fluidity and rubber properties.
For example, calcium carbonate, calcium silicate, clay, kaolin, talc, silica, diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, aluminum sulfate, calcium sulfate, basic magnesium carbonate, molybdenum disulfide, graphite, glass fiber, glass Spheres, shirasu balloons, carbon fibers and the like or colorants such as carbon black, titanium oxide, zinc white, red iron oxide, ultramarine blue,
Navy blue, azo pigments, nitroso pigments, lake pigments, phthalocyanine pigments and the like can be blended, and further, if necessary, antioxidants, ultraviolet absorbers, stabilizers such as metal deterioration inhibitors, lubricants, antistatic agents, Additives usually added to resins or rubbers such as electrical property improvers, flame retardants, processability improvers and the like can be added.

Applications of the thermoplastic elastomer composition of the present invention include automobile interior and exterior parts such as body panels, bumper parts, side shields and steering wheels,
It can be used for civil engineering and construction related materials, industrial machine parts such as gaskets, medical related equipment, housings, electric wire coatings, connectors, OA parts such as cap plugs, leisure goods, garden hoses, belts, and miscellaneous goods such as footwear.

[0028]

EXAMPLES The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples without departing from the gist thereof.
The following raw materials were used in the examples and comparative examples of the present invention. 1. Peroxide cross-linking olefin copolymer rubber EPDM: ethylene-propylene-ethylidene norbornene copolymer rubber [Moonie viscosity ML 1 + 4 (100
℃) = 88, iodine value 15.0, propylene content 28
%] 2. Peroxide decomposition type olefin-based plastic BPP: propylene-ethylene block copolymer [density 0.90 g / cm ³ , melt flow rate (MFR, 2
30 ° C., 2.16 kg load) 40 g / 10 minutes, ethylene content 7% by weight] 3. Peroxide cross-linking olefin plastic LDPE: Low density polyethylene [Density 0.92 g / cm
³ , melt index (MI, 190 ℃, 2.16k
g load) 0.24] 4. Mineral oil-based softener Oil: Paraffin-based softener [Density at 15 ° C. 0.870
0 g / cm ³ viscosity index 110] 5. Bismaleimide compound BMI: N, N'-m-phenylene bismaleimide 6. Organic peroxide POX: 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,6. Cross-linking aid DVB: Divinylbenzene

(Embodiment 1) Twin-screw kneader TEX rotating in the same direction
BPP (25 parts by weight) and POX (0.05 parts by weight) were put into a No. 54 (manufactured by Japan Steel Works) No. 1 hopper and decomposed in a decomposition zone at a cylinder temperature of 280 ° C. The MFR of the obtained BPP was 210 g / 10 minutes. From the second hopper to the BPP decomposed in the decomposition zone, EPDM: 55 parts by weight, LDPE: 20 parts by weight, BMI: 3.0 parts by weight, P
OX: 0.12 parts by weight was added, dynamic heat treatment was carried out in a heat treatment zone at a cylinder temperature of 200 ° C. in a nitrogen atmosphere to terminate the crosslinking reaction, and Oil: 40 parts by weight was supplied from a nozzle provided at the crosslinking reaction end position. Injection, cylinder temperature 200 ℃
Oil was kneaded in the zone to prepare a thermoplastic elastomer composition. The evaluation results of the obtained composition are shown in Table 1.

Example 2 A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of EPDM added was 65 parts by weight and the amount of LDPE added was 10 parts by weight. The evaluation results of the obtained composition are shown in Table 1. (Example 3) The amount of EPDM added was 35 parts by weight, and LD
A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of PE added was 40 parts by weight. The evaluation results of the obtained composition are shown in Table 1. (Example 4) The amount of EPDM added was 25 parts by weight, and LD
A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of PE added was 50 parts by weight. The evaluation results of the obtained composition are shown in Table 1. (Example 5) DVB was further added to the composition of Example 1 by 0.18.
A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the addition of parts by weight was added. The evaluation results of the obtained composition are shown in Table 1. (Example 6) A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the added amount of BMI was 1.0 part by weight.

Table 1 shows the evaluation results of the obtained composition. (Example 7) A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the added amount of BMI was changed to 10 parts by weight. The evaluation results of the obtained composition are shown in Table 1. (Example 8) A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of Oil added was 80 parts by weight. The evaluation results of the obtained composition are shown in Table 1.

Comparative Example 1 A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of EPDM added was 75 parts by weight and LDPE was not added. The evaluation results of the obtained composition are shown in Table 1. (Comparative Example 2) The amount of EPDM added was 15 parts by weight, and LD
A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the amount of PE added was 60 parts by weight. The evaluation results of the obtained composition are shown in Table 1. (Comparative Example 3) A thermoplastic elastomer composition was produced in the same manner as in Example 4 except that BMI was not added.
The evaluation results of the obtained composition are shown in Table 1.

Comparative Example 4 A thermoplastic elastomer composition was produced in the same manner as in Example 1 except that the added amount of BMI was 25 parts by weight. The evaluation results of the obtained composition are shown in Table 1.

[0034]

[Table 1] From Table 1, BPP was decomposed with organic peroxide, and the components which were still in a molten state were added with the remaining components including peroxide cross-linking olefin plastic and bismaleimide compound, and subjected to dynamic heat treatment to partially It can be seen that the compositions of Examples 1 to 8 which were subjected to the crosslinking reaction in Example 1 showed balanced physical properties as compared with Comparative Examples 1 to 4.

Next, in order to check the blocking resistance of the pellets after molding in the thermoplastic elastomer composition, the following test was conducted. The thermoplastic elastomer composition produced is usually a pelletizer and has a particle size of 3-4.
25k in a packing bag such as a paper bag after being molded into pellets of about mm
Filled in g units, length 75 cm, width 45 cm, width 15 c
It is stored and shipped as a bag of m. In this case, 5 bags of bagging are arranged in a row on a pallet, and then stacked or stored in 4 or 8 steps before shipping. Then, the load applied to the bottom of the case where the stacked four stages and eight steps, were respectively ^{22g / cm 2, 52g / cm} 2. Therefore, a paper bag was packed with each of the pellets of the thermoplastic elastomer composition obtained in Example 4 and Comparative Example 3 to form a bag filling having a length of 10 cm and a width of 15 cm (bottom area 150 cm ² ). Add 3.3kg load corresponding to the bottom and 7.8kg load corresponding to the bottom when 8 layers are stacked and leave at room temperature 40 ° C, 50 ° C, 60 ° C for 1 day, 3 days, 6 days The degree of blocking of the contents was examined and the results were as shown in Table 2.

[0036]

[Table 2] Here, the degree of blocking is ⊚: no blocking at all, ∘: solidified (disintegrated by light impact), Δ:
Partially blocked, x: Entirely blocked. As can be seen from Table 2, the thermoplastic elastomer composition of the present invention has good blocking resistance.

[0037]

As described above, in the present invention, the method for producing a thermoplastic elastomer composition found by the present inventors has been applied to a mixture containing a bismaleimide compound and containing a peroxide-crosslinking olefin plastic. By applying, it can be molded with the equipment used for ordinary thermoplastics, extrusion molding, calender molding,
Suitable for injection molding, and because the olefinic copolymer rubber component is partially cross-linked, heat resistance, weather resistance,
It has excellent rubber-like properties such as tensile properties, flexibility and impact resilience, and has good fluidity, so it has excellent moldability,
In addition, a thermoplastic elastomer composition was obtained which was a high-strength product while maintaining high strength due to a high degree of crosslinking, high filling of a mineral oil-based softening agent and high processability.

Claims (2)

[Claims] 1. (a) 5 to 85 parts by weight of a peroxide-crosslinking olefin copolymer rubber, (b) 10 to 50 parts by weight of a peroxide decomposing olefin plastic,
(C) 5 to 55 parts by weight of peroxide-crosslinked olefin-based plastic [provided that (a) + (b) + (c) = 100
Parts by weight] and (d) bismaleimide compound 0.1 to 20 parts by weight and (e) organic peroxide 0.
In a thermoplastic elastomer composition which has been subjected to a dynamic heat treatment in the presence of 01 to 5 parts by weight and partially cross-linked, (a), (c), (d) and (e) immediately after (b) is pre-degraded. ) Is added thereto and the mixture is subjected to a dynamic heat treatment to partially crosslink the thermoplastic elastomer composition. 2. (a) 5 to 85 parts by weight of a peroxide-crosslinking olefin copolymer rubber, (b) 10 to 50 parts by weight of a peroxide-decomposing olefin plastic,
(C) 5 to 55 parts by weight of peroxide-crosslinked olefin-based plastic [provided that (a) + (b) + (c) = 100
Parts by weight] and (d) bismaleimide compound 0.1 to 20 parts by weight and (e) organic peroxide 0.
In a thermoplastic elastomer composition which has been subjected to a dynamic heat treatment in the presence of 01 to 5 parts by weight and partially cross-linked, (a), (c), (d) and (e) immediately after (b) is pre-degraded. ) Is added thereto to carry out dynamic heat treatment to terminate the partial crosslinking reaction, and then (f) a mineral oil-based softening agent is added.