JP2020164700A - ETHYLENE/α-OLEFIN/VINYLNORBORNENE COPOLYMER COMPOSITION AND CROSSLINKED PRODUCT THEREOF - Google Patents

Abstract

To obtain a thermoplastic elastomer composition which has good fluidity and is capable of providing a molding having good compression set and excellent oil resistance.SOLUTION: The present invention relates to an ethylene/α-olefin/vinylnorbornene copolymer composition containing: 100 pts.mass of an ethylene/α-olefin/vinylnorbornene copolymer (A) containing ethylene, a C3 or higher α-olefin, and vinylnorbornene as constituent units; and 10-300 pts.mass of a crystalline olefinic polymer (B).SELECTED DRAWING: None

Description

The present invention relates to an ethylene / α-olefin / vinylnorbornene copolymer composition, and more specifically, an ethylene / α-olefin capable of providing a molded product having good fluidity, good compression set, and excellent oil resistance. -Regarding vinyl norbornene copolymer compositions and crosslinked products thereof.

An olefin-based thermoplastic elastomer obtained by cross-linking a composition of an ethylene / α-olefin / non-conjugated polyene copolymer and a crystalline olefin polymer, which is a type of thermoplastic elastomer, is lightweight and easy to recycle. As an energy-saving and resource-saving type thermoplastic elastomer, as an alternative to vulcanized rubber, it is widely used for automobile parts such as hoses, pipes and boots (blow-molded products) for automobiles (for example, Patent Document 1). And 2).

However, in these automobile parts, weight reduction is always required to improve fuel efficiency, but since the thermoplastic elastomer used contains a large amount of filler, the specific gravity tends to be large, which hinders the weight reduction of parts. Was. Further, these automobile parts are used in places where they come into contact with lubricating oils, greases, etc. However, in general, olefin-based thermoplastic elastomers have low oil resistance to paraffin-based process oils, and thus olefin-based heat. These automobile parts obtained by containing the thermoplastic elastomer also have low oil resistance, and further improvement is required.

Japanese Unexamined Patent Publication No. 2001-294714 Japanese Unexamined Patent Publication No. 2011-202136

An object of the present invention is to obtain a thermoplastic elastomer composition which can provide a molded product having good fluidity, good compression set, and excellent oil resistance.

The present invention contains 100 parts by mass of an ethylene / α-olefin / vinylnorbornene copolymer (A) and a crystalline olefin polymer (B) containing ethylene, α-olefin having 3 or more carbon atoms, and vinylnorbornene as constituent units. ) The ethylene / α-olefin / vinylnorbornene copolymer composition comprising 10 to 300 parts by mass, and a crosslinked product of the copolymer composition.

The crosslinked product obtained by cross-linking the ethylene / α-olefin / vinylnorbornene copolymer composition of the present invention has higher fluidity than the crosslinked product of the ethylene / α-olefin / ENB copolymer that has been widely used in the past. It is possible to provide a molded product having good properties, good compression set, and excellent oil resistance.

It is the schematic of the continuous polymerization apparatus used in an Example.

<Ethylene / α-olefin / vinyl norbornene copolymer (A)>
Ethylene / α-olefin / vinylnorbornene copolymer (A), which is one of the components contained in the copolymer composition according to the present invention [hereinafter, may be abbreviated as "copolymer (A)". ] Is a copolymer containing ethylene, an α-olefin having 3 or more carbon atoms, and vinyl norbornene as constituent units.

The copolymer (A) according to the present invention preferably has a structural unit derived from ethylene (a1), an α-olefin (a2) having 3 to 20 carbon atoms, and vinyl norbornene (a3).

Examples of the α-olefin (a2) include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, and the like. Examples thereof include 1-tetradecene, 1-hexadecene, and 1-eikosen. Of these, α-olefins having 3 to 8 carbon atoms such as propylene, 1-butene, 1-hexene, and 1-octene are preferable, and propylene is particularly preferable. Such α-olefins are preferable because the raw material cost is relatively low, the obtained copolymer (A) exhibits excellent mechanical properties, and a molded product having rubber elasticity can be obtained.

The α-olefin (a2) may be used alone or in combination of two or more. That is, the copolymer (A) contains a structural unit derived from at least one type of α-olefin (a2) having 3 to 20 carbon atoms, and two or more types of α having 3 to 20 carbon atoms. -It may contain a structural unit derived from the olefin (a2).

The vinyl norbornene (a3) is a compound having two or more unconjugated unsaturated bonds, which is also called 5-vinyl-2-norbornene (VNB).
The copolymer (A) according to the present invention is further selected from the group consisting of the above general formulas (I) and (II) in addition to the structural units derived from the above (a1), (a2) and (a3). It may have a structural unit derived from a non-conjugated polyene (a4) containing only one partial structure in the molecule.

Examples of the non-conjugated polyene (a4) include 5-ethylidene-2-norbornene (ENB), 5-methylene-2-norbornene, 5- (2-propenyl) -2-norbornene, and 5- (3-butenyl) -2. -Norbornene, 5- (1-methyl-2-propenyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (1-methyl-3-butenyl) -2-norbornene, 5-( 5-hexenyl) -2-norbornene, 5- (1-methyl-4-pentenyl) -2-norbornene, 5- (2,3-dimethyl-3-butenyl) -2-norbornene, 5- (2-ethyl- 3-butenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene, 5- (3-methyl-5-hexenyl) -2-norbornene, 5- (3,4-dimethyl-4-pentenyl) -2-Norbornene, 5- (3-ethyl-4-pentenyl) -2-Norbornene, 5- (7-octenyl) -2-Norbornene, 5- (2-Methyl-6-Heptenyl) -2-Norbornene, 5 -(1,2-dimethyl-5-hexenyl) -2-norbornene, 5- (5-ethyl-5-hexenyl) -2-norbornene, 5- (1,2,3-trimethyl-4-pentenyl) -2 -Norbornene and the like. Of these, ENB is preferable because it is highly available, highly reactive with sulfur and vulcanization accelerators during the cross-linking reaction after polymerization, the cross-linking rate can be easily controlled, and good mechanical properties can be easily obtained. .. The non-conjugated polyene (a4) may be used alone or in combination of two or more.

When the copolymer (A) according to the present invention contains a structural unit derived from the non-conjugated polyene (a4), the proportion thereof is not particularly limited as long as the object of the present invention is not impaired, but is usually used. , 0 to 20% by weight, preferably 0 to 8% by weight, more preferably 0.01 to 8% by weight (however, (a1), (a2), (a3), (a4). The total weight fraction of is 100% by weight).

The copolymer (A) according to the present invention preferably satisfies the following requirements (i) to (iv) (hereinafter, also referred to as requirements (i) to (iv), respectively).
(I) The molar ratio [(a1) / (a2)] of the structural unit derived from ethylene (a1) to the structural unit derived from α-olefin (a2) is 40/60 to 99.9 / 0. It is 1.
(Ii) The weight fraction of the structural unit derived from vinyl norbornene (a3) is 0.07% by weight to 10% by weight in 100% by weight of the copolymer (A).
(Iii) The ratio (molecular weight distribution; Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 8 to 30.
(Iv) The number average molecular weight (Mn) is 30,000 or less.

≪Requirement (i) ≫
Requirement (i) specifies that the molar ratio of ethylene (a1) / α-olefin (a2) in the copolymer (A) satisfies 40/60 to 99.9 / 0.1. The molar ratio is preferably 50/50 to 90/10, more preferably 55/45 to 85/15, and even more preferably 55/45 to 78/22.

By using the copolymer (A) satisfying the requirement (i), it is possible to obtain a vibration-proof rubber having excellent rubber elasticity, mechanical strength and flexibility. The amount of ethylene (content of the structural unit derived from ethylene (a1)) and the amount of α-olefin (content of the structural unit derived from α-olefin (a2)) in the copolymer (A) are ¹³ C-. It can be obtained by NMR.

≪Requirements (ii) ≫
The requirement (ii) is that the weight fraction of the constituent unit derived from vinyl norbornene (a3) is in 100% by weight of the copolymer (A) (that is, in the total weight fraction of all the constituent units in 100% by weight). It specifies that it is in the range of 0.07% by weight to 10% by weight. The weight fraction of the structural unit derived from this vinyl norbornene (a3) is preferably 0.1% by weight to 8.0% by weight, and more preferably 0.5% by weight to 5.0% by weight.

The copolymer (A) satisfying the requirement (ii) has sufficient hardness and excellent mechanical properties, and when crosslinked using a peroxide, it exhibits a high crosslinking rate. The amount of vinyl norbornene (a3) in the copolymer (A) (content of the structural unit derived from vinyl norbornene (a3)) can be determined by ¹³ C-NMR.

≪Requirements (iii)≫
Requirement (iii) is the ratio (molecular weight distribution; Mw / Mn) of the above-mentioned copolymer (A) to the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC). ) Is in the range of 8 to 30. This molecular weight distribution (Mw / Mn) is preferably in the range of 9 to 28, more preferably 10 to 26.

When the copolymer (A) satisfies the requirement (v), the low molecular weight component is contained in an appropriate amount, so that the processability is improved.
The weight average molecular weight (Mw) and the number average molecular weight of the copolymer (A) can be determined as polystyrene-equivalent values measured by gel permeation chromatography (GPC).

≪Requirements (iv) ≫
Requirement (iv) specifies that the number average molecular weight (Mn) of the copolymer (A) is 30,000 or less. The number average molecular weight (Mn) is preferably in the range of 3,000 to 26,000, more preferably 6,000 to 23,000.
When the copolymer (A) satisfies the requirement (vi), the low molecular weight component is contained in an appropriate amount, so that the processability is improved.

<Method for producing ethylene / α-olefin / vinyl norbornene copolymer (A)>
The ethylene / α-olefin / vinylnorbornene copolymer (A) according to the present invention includes ethylene (a1), α-olefin (a2), vinylnorbornene (a3), and if necessary, a non-conjugated polyene (a3). It is a copolymer obtained by copolymerizing a monomer composed of a4).

The copolymer (A) according to the present invention may be prepared by any production method as long as the above requirements (i) to (iv) are satisfied, but the monomer is copolymerized in the presence of the metallocene compound. It is preferable that the product is obtained by copolymerizing a monomer in the presence of a catalyst system containing a metallocene compound, and more preferably.

As a specific method for producing the above-mentioned copolymer (A) according to the present invention, for example, a production method using a metallocene catalyst described in JP-A-2018-119096 and International Publication No. 2015/122495 is adopted. It can be manufactured by.

<Crystalline olefin polymer (B)>
A crystalline olefin polymer which is one of the components contained in the copolymer composition according to the present invention [hereinafter, may be referred to as "polymer (B)". ] Is a homopolymer or copolymer of an α-olefin having 2 to 20 carbon atoms and a crystalline polymer.
In the present invention, the crystalline polymer is a polymer having a melting point.

Specific examples of the α-olefin constituting the crystalline olefin polymer (B) include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, and 3-methyl-. Examples thereof include 1-pentene, 4-methyl-1-pentene and 5-methyl-1-hexene.

Specific examples of the crystalline olefin polymer (A) according to the present invention include the following (co) polymers.
(1) A homopolymer of ethylene and a copolymer of ethylene and other α-olefins of 10 mol% or less or vinyl monomers such as vinyl acetate and ethyl acrylate, more specifically, high-pressure low-density polyethylene, wire. It is an ethylene polymer such as low density polyethylene (LLDPE), medium density polyethylene, high density polyethylene (HDPE), ethylene / vinyl acetate copolymer (EVA), and ethylene / acrylic acid copolymer.
(2) Propylene such as a homopolymer of propylene, a random copolymer of propylene and 10 mol% or less of other α-olefins, and a block copolymer of propylene and 30 mol% or less of other α-olefins. It is a system polymer, and is also generally called homo, random, or block type polypropylene.
(3) A 1-butene-based polymer such as a homopolymer of 1-butene and a random copolymer of 1-butene and another α-olefin of 10 mol% or less.
(4) Examples thereof include a homopolymer of 4-methyl-1-pentene and a random copolymer of 4-methyl-1-pentene and another α-olefin of 20 mol% or less.

These crystalline olefin polymers (B) can be used alone or in combination of two or more.
Among these crystalline olefin polymers (B), a propylene-based polymer is preferable.

The propylene-based polymer preferably has an isotactic structure as the three-dimensional structure, but a syndiotactic structure, a mixture of these structures, or a structure containing a part of the atactic structure can also be used.

The propylene-based polymer usually has a melt flow rate (measured at a temperature of 230 ° C. and a load of 21.18 N according to JIS K6758) preferably 0.05 to 100 g / 10 minutes, more preferably 0.1. ~ 50 g / 10 minutes.

<Ethylene / α-olefin / vinylnorbornene copolymer composition>
Ethylene / α-olefin / vinylnorbornene copolymer composition of the present invention [hereinafter, may be abbreviated as "copolymer composition". ] Is 10 to 300 parts by mass, preferably 10 to 300 parts by mass of the crystalline olefin polymer (B) with respect to 100 parts by mass of the ethylene / α-olefin / vinylnorbornene copolymer (A) and the copolymer (A). The composition contains 20 to 280 parts by mass, more preferably 30 to 250 parts by mass.

In addition to the above-mentioned copolymer (A) and the above-mentioned polymer (B), the copolymer composition of the present invention has a softening agent, a heat-resistant stabilizer, an antistatic agent, a weather-resistant stabilizer, and an anti-aging agent, if necessary. , Fillers, colorants, lubricants and other additives can be blended within a range that does not impair the object of the present invention.

<Softener>
Specific examples of the softener according to the present invention include petroleum-based softeners such as process oil, lubricating oil, paraffin oil, liquid paraffin, petroleum asphalt, and vaseline; hydrocarbon softeners such as coal tar; castor oil, and flaxseed oil. , Petroleum-based softeners such as rapeseed oil, soybean oil, and coconut oil; waxes such as beeswax and carnauba wax; fatty acids such as ricinolic acid, palmitic acid, stearic acid, barium stearate, and calcium stearate or salts thereof; naphthenic acid , Pine oil, rosin or derivatives thereof; synthetic polymer substances such as terpene resin, petroleum resin, kumaron inden resin; ester-based softeners such as dioctylphthalate and dioctyl adipate; and other microcrystallin wax, liquid polybutadiene, modified liquid polybutadiene , Hydrocarbon-based synthetic lubricating oil, tall oil, sub (factis) and the like, petroleum-based softeners are preferable, and process oils are particularly preferable.
The blending amount of the softening agent in the copolymer composition is generally 2 to 100 parts by mass, preferably 10 to 100 parts by mass with respect to 100 parts by mass of the copolymer (A).

<Inorganic filler>
As a specific example of the inorganic filler according to the present invention, one or more types such as light calcium carbonate, heavy calcium carbonate, talc, clay and the like are used, and among these, "Whiten SB" (trade name). Shiraishi Calcium Co., Ltd.) and other heavy calcium carbonates are preferable.

When the copolymer composition contains an inorganic filler, the blending amount of the inorganic filler is usually 2 to 50 parts by mass, preferably 5 to 50 parts by mass with respect to 100 parts by mass of the copolymer A). It is a mass part. When the blending amount is within the above range, the kneading processability of the copolymer composition is excellent.

<Reinforcing agent>
Specific examples of the reinforcing agent according to the present invention include carbon black, carbon black surface-treated with a silane coupling agent, silica, calcium carbonate, activated calcium carbonate, fine talc, fine powder silicic acid, and the like, and when blended. Is generally 30 to 200 parts by mass, preferably 50 to 180 parts by mass with respect to 100 parts by mass of the copolymer (A).

<Anti-aging agent (stabilizer)>
By blending an antiaging agent (stabilizer) with the copolymer composition according to the present invention, the life of the molded product to be formed can be extended. Examples of such an antiaging agent include conventionally known anti-aging agents such as amine-based anti-aging agents, phenol-based anti-aging agents, and sulfur-based anti-aging agents.

Further, as an anti-aging agent, an aromatic secondary amine-based anti-aging agent such as phenylbutylamine, N, N-di-2-naphthyl-p-phenylenediamine; dibutylhydroxytoluene, tetrakis [methylene (3,5-di-) t-Butyl-4-hydroxy) hydrocinnamate] Phenolic anti-aging agents such as methane; thioethers such as bis [2-methyl-4- (3-n-alkylthiopropionyloxy) -5-t-butylphenyl] sulfide Anti-aging agent; Dithiocarbamate-based anti-aging agent such as nickel dibutyldithiocarbamate; 2-mercaptobenzoylimidazole, 2-mercaptobenzoimidazole, 2-mercaptobenzoimidazole zinc salt, dilaurylthiodipropionate, distearylthio There are sulfur-based antioxidants such as dipropionate.

These anti-aging agents can be used alone or in combination of two or more, and the blending amount thereof is usually 0.3 to 10 parts by mass with respect to 100 parts by mass of the copolymer (A). , Preferably 0.5 to 7.0 parts by mass. Within such a range, there is no bloom on the surface of the molded product obtained from the crosslinked product of the copolymer composition, and the occurrence of vulcanization inhibition can be further suppressed.

<Processing aid>
As the processing aid according to the present invention, those generally blended with rubber as a processing aid can be widely used.

Specific examples of the processing aid include ricinoleic acid, stearic acid, palmitic acid, lauric acid, barium stearate, zinc stearate, calcium stearate, esters and the like. Of these, stearic acid is preferred.
The blending amount of the processing aid is usually 10 parts by mass or less, preferably 8.0 parts by mass or less, based on 100 parts by mass of the copolymer (A) contained in the copolymer composition.

<Activator>
Specific examples of the activator include amines such as di-n-butylamine, dicyclohexylamine and monoeranolamine; zinc compounds of diethylene glycol, polyethylene glycol, lecithin, trialilute melilate, aliphatic carboxylic acid or aromatic carboxylic acid. Activators; Zinc peroxide modifiers; Cutadecyltrimethylammonium bromide, synthetic hydrotalcites, special quaternary ammonium compounds, etc.
When the activator is contained, the blending amount thereof is usually 0.2 to 10 parts by mass, preferably 0.3 to 5 parts by mass with respect to 100 parts by mass of the copolymer (A).

<Moisture absorbent>
Specific examples of the hygroscopic agent include calcium oxide, silica gel, sodium sulfate, molecular sieve, zeolite, white carbon and the like.
When the hygroscopic agent is contained, the blending amount thereof is usually 0.5 to 15 parts by mass, preferably 1.0 to 12 parts by mass with respect to 100 parts by mass of the copolymer (A).

<Crosslinked product of copolymer composition>
The crosslinked product of the copolymer composition of the present invention is obtained by cross-linking the above-mentioned copolymer composition of the present invention.
In order to cross-link the copolymer composition of the present invention, a cross-linking agent such as an organic peroxide is added to the above-mentioned copolymer composition, and then the copolymer composition is cross-linked.

<Organic peroxide>
Specific examples of the organic peroxide used as a cross-linking agent include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane, and 2,5-. Dimethyl-2,5-di- (tert-butylperoxy) hexin-3, 1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5- Trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate, Examples thereof include diacetyl peroxide, lauroyl peroxide, and tert-butylcumyl peroxide.

Of these, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane and 2,5-dimethyl-2,5-di- (tert-butyl) in terms of odor and scorch stability. Peroxy) Hexin-3, 1,3-bis (tert-butyl peroxyisopropyl) benzene, 1,1-bis (tert-butyl peroxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (Tert-Butylperoxy) valerate is preferred, with 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane and 1,3-bis (tert-butylperoxyisopropyl) benzene being the most preferred.
The blending amount of the organic peroxide is usually 0.05 to 3 parts by mass, preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the copolymer (A).

<Crossing aids, etc.>
In the cross-linking treatment with the above organic peroxide, sulfur, p-quinone dioxime, p, p'-dibenzoylquinone dioxime, N-methyl-N-4-dinitrosoaniline, nitrosobenzene, diphenylguanidine, trimethylolpropane, N. .. Crosslinking aids such as N'-m-phenylenedimaleimide, divinylbenzene, triallyl cyanurate, or many such as ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate. Functional methacrylate monomer; Polyfunctional vinyl monomers such as vinyl butyrate and vinyl stearate can be blended.

By using the above compound, a uniform and mild cross-linking reaction can be expected. In particular, in the present invention, divinylbenzene is most preferable. Divinylbenzene is easy to handle, has good compatibility with the copolymer (A) and the polymer (B), which are the main components of the crosslinked product, and has an action of solubilizing organic peroxide. However, since it acts as a dispersant for organic peroxides, it has a homogeneous cross-linking effect due to heat treatment and has a well-balanced fluidity and physical properties [hereinafter, it may be referred to as a “thermoplastic elastomer composition”. ] Is obtained.

The cross-linking aid improves the fluidity of the obtained thermoplastic elastomer composition, and prevents changes in physical properties due to thermal history during processing and molding, with respect to 100 parts by mass of the composition. Therefore, it is preferably used in a proportion of 0.1 to 2 parts by mass, particularly 0.3 to 1 part by mass.

As a method for cross-linking the copolymer composition of the present invention, after mixing the copolymer composition and the organic peroxide or the like, a conventionally known kneading device such as an open mixing roll or a non-open Banbury mixer can be used. Extruders, kneaders, continuous mixers, etc. are used. Of these, a non-open type kneading device is preferable, and the kneading is preferably performed in an atmosphere of an inert gas such as nitrogen gas or carbon dioxide gas.

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

When the copolymer composition of the present invention is crosslinked, it is preferable to knead and crosslink as described above and then statically heat-treat in hot air. Here, "statically heat-treating" means keeping the temperature below the melting point for a certain period of time in a state of standing or stirring.

At that time, the static heat treatment is performed under the following conditions: Q ≧ 0.1 and t ≧ 2- ^{(T-110) / 10} (However, Q is the amount of hot air per unit weight of the object to be processed (m ⁾ supplied during drying. ³ / (hours / kg)), t is the heat treatment time (hours), and T is the temperature of the hot air immediately before hitting the object to be treated (° C.)), so that most of the low molecular weight components are removed. An olefin-based thermoplastic elastomer composition having better fogging resistance can be obtained.
The thermoplastic elastomer composition of the present invention may be completely crosslinked, but is preferably partially crosslinked.

<< Applications of thermoplastic elastomers >>
The thermoplastic elastomer composition of the present invention is molded by a commonly used molding method, for example, an injection molding method, an extrusion molding method, a hollow molding method, a compression molding method, or the like. Applications include automobile parts (weather strips, ceiling materials, interior seats, bumper moldings, side moldings, air spoilers, air duct hoses, cup holders, side brake grips, shift knob covers, seat adjustment knobs, flapper door seals, wire harness glomets, rack and Pinion boots, suspension cover boots, glass guides, inner belt line seals, roof guides, trunk lid seals, molded quarter wind gaskets, corner moldings, glass encapsulation, hood seals, glass run channels, secondary seals, various packings, etc. ), Civil and building material parts (water blocking material, joint material, building window frame, etc.), sports equipment (golf club, tennis racket grips, etc.), industrial parts (hose tube, gasket, etc.), home appliance parts (hose) , Packing, etc.), medical equipment parts, electric wires, miscellaneous goods, etc. Used as materials in a wide range of fields.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.
The polymers used in Examples and Comparative Examples are shown below.

(1) Ethylene / α-olefin / vinylnorbornene copolymer (A)
As the ethylene / α-olefin / vinylnorbornene copolymer (A), the ethylene / propylene / VNB copolymer (A-1) obtained by the following production method was used.
The ethylene / propylene / VNB copolymer (A-1) was produced using the continuous polymerization apparatus shown in FIG.

In a polymerization reactor C having a volume of 300 liters, 58.3 L / hr of hexane solvent dehydrated and purified from tube 6 and 4.5 mmol / hr of triisobutylaluminum (TiBA) from tube 7, (C ₆ H ₅ ) ₃ CB ( C ₆ F ₅ ) ₄ was continuously supplied at 0.150 mmol / hr, and di (p-tolyl) methylene (cyclopentadienyl) (octamethyloctahydrodibenzofluorenyl) zirconium dichloride was continuously supplied at 0.030 mmol / hr. .. At the same time, ethylene was continuously supplied into the polymerization reactor C at 6.6 kg / hr, propylene at 9.3 kg / hr, hydrogen at 18 liters / hr, and VNB at 340 g / hr, respectively, from tubes 2, 3, 4, and 5, respectively. Then, copolymerization was carried out under the conditions of a polymerization temperature of 87 ° C., a total pressure of 1.6 MPaG, and a residence time of 1.0 hour.

The ethylene / propylene / VNB copolymer solution produced in the polymerization reactor C is continuously discharged through the tube 8 at a flow rate of 88.0 liters / hr and raised to a temperature of 170 ° C. (pressure is 4.1 MPaG). Was supplied to the phase separator D. At this time, ethanol, which is a polymerization inhibitor, was continuously introduced into the tube 8 in an amount of 0.1 mol times that of TiBA in the liquid component extracted from the polymerization reactor C.

In the phase separator D, a solution of the ethylene / propylene / VNB copolymer is mixed with a concentrated phase (lower phase portion) containing most of the ethylene / propylene / VNB copolymer and a dilute phase (upper phase portion) containing a small amount of polymer. ) And separated.

The separated concentrated phase is led to the heat exchanger K via the tube 11 at 85.4 liters / hr, and further led into the hopper E, where the solvent is evaporated and separated to form an ethylene / propylene / VNB copolymer. Was obtained in an amount of 7.8 kg / hr.

The physical properties of the obtained ethylene / propylene / VNB copolymer (A-1) were measured by the method described below. The results are shown in Table 1. The molecular weight distribution of the obtained copolymer (A-1) was bimodal.

(2) Crystalline olefin polymer (B)
As a crystalline olefin polymer (B), an MFR: 2.0 g / 10 min (230 ° C., 2.16 kg load) propylene homopolymer [Prime Polymer Co., Ltd. trade name Prime Polypro E-200GP] (B-1) ) Was used.

(3) Ethylene / propylene / ENB copolymer (E-1)
Ethylene content: 65% by weight, ENB content: 4.6% by weight, Mooney viscosity ML (1 + 4) 125 ° C: 61 [Mitsui Chemicals, Inc. trade name Mitsui EPT 3092M]
The composition of the ethylene / propylene / VNB copolymer (A-1) was measured by the method described below.

<Composition of ethylene / propylene / VNB copolymer>
The weight fraction (% by weight) of each constituent unit of the ethylene / propylene / VNB copolymer was determined by the value measured by ¹³ C-NMR. The measured values were measured using an ECX400P type nuclear magnetic resonance device (manufactured by JEOL Ltd.) at a measurement temperature of 120 ° C., a measurement solvent: orthodichlorobenzene / deuterated benzene = 4/1, and an integration number of 8000 times. It was obtained by measuring the ¹³ C-NMR spectrum of the polymer.

<Iodine value>
The iodine value of the ethylene / propylene / VNB copolymer was determined by the titration method. Specifically, it was measured by the following method.

0.5 g of an ethylene / propylene / VNB copolymer was dissolved in 60 ml of carbon tetrachloride, a small amount of whistle reagent and a 20% potassium iodide solution were added, and the mixture was optimized with a 0.1 mol / L sodium thiosulfate solution. A starch indicator was added near the end point, and the temperature was adjusted until the lilac disappeared while stirring well, and the number of g of iodine was calculated as the amount of halogen consumed per 100 g of the sample.

<Ultimate viscosity>
The ultimate viscosity [η] of the ethylene / propylene / VNB copolymer was measured using a fully automatic ultimate viscometer manufactured by Rigo Co., Ltd. at a temperature of 135 ° C. and a measurement solvent of decalin.

<Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution (Mw / Mn)>
The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of the ethylene / propylene / VNB copolymer are polystyrene-equivalent values measured by gel permeation chromatography (GPC). .. The measuring device and conditions are as follows. In addition, the molecular weight was calculated based on a conversion method by preparing a calibration curve using commercially available monodisperse polystyrene.
Equipment: Gel permeation chromatograph Alliance GP2000 type (manufactured by Waters),
Analyst: Emper2 (manufactured by Waters),
Column: TSKgel GMH6-HT x 2 + TSKgel GMH6-HTL x 2 (7.5 mm I.D. x 30 cm, manufactured by Tosoh Corporation),
Column temperature: 140 ° C,
Mobile phase: o-dichlorobenzene (containing 0.025% BHT),
Detector: Differential Refractometer (RI), Flow Velocity: 1.0 mL / min,
Injection volume: 400 μL,
Sampling time interval: 1s,
Column calibration: Monodisperse polystyrene (manufactured by Tosoh),
Molecular weight conversion: Old method EPR conversion / Calibration method considering viscosity.

<Low molecular weight component>
When the chart obtained by the above GPC measurement shows two or more peaks, the ratio (%) of the area of the peak appearing on the side with the smallest molecular weight to the total peak area is 2000 or less. The content of low molecular weight components was used. When the chart obtained by GPC measurement showed only one peak, the content of the low molecular weight component was set to 0%.

[Example 1]
[Preparation of copolymer composition]
Using a lab plast mill [4C150, model: R60H type mixer, capacity: about 60cc (effective kneading volume: 48cc)] manufactured by Toyo Seiki Seisakusho, the kneading temperature was set to 200 ° C., and the above copolymer (A-1) was used. ): 100 parts by mass and the above polymer (B-1): 71 parts by weight were charged at a rotation speed of 10 rpm. Then, the rotation speed was rapidly increased in the order of 10 rpm (10 seconds) → 30 rpm (10 seconds) → 50 rpm (10 seconds) → 70 rpm (10 seconds) → 90 rpm (10 seconds), and this was repeated for 3 sets. Next, at a rotation speed of 10 rpm, 114 parts by mass of (general name description) (manufactured by Idemitsu Kosan Co., Ltd., trade name Diana Process Oil, PW-100): 114 parts by mass is gradually dropped so that the rotor does not run idle. Then, after rapidly increasing the rotation speed from 10 rpm → 30 rpm → 50 rpm → 70 rpm → 90 rpm, the rotation speed was set to 10 rpm as a phenolic antioxidant (statement of compound name) (manufactured by BASF Japan Ltd., trade name Iruga). Knox 1010): 0.4 parts by mass and zinc oxide (manufactured by HakusuiTech Co., Ltd., 2 types of zinc oxide): 1.4 parts by mass are added, and then the copolymer composition is waited for the resin temperature to drop to 200 ° C. Got

[Manufacturing of crosslinked products]
Next, in the above-mentioned copolymer composition whose temperature was maintained at 200 ° C., 4 parts by mass of an organic peroxide (statement of compound name) (manufactured by Nippon Steel Co., Ltd., trade name Perhexa 25B) was used as a cross-linking aid ( Description of compound name) (Nippon Steel & Sumikin Chemical Co., Ltd., trade name DVB-810) was added in an amount of 2.4 parts by mass, and the above PW-100 as a softening agent was added in an amount of 2.6 parts by mass. It was rapidly increased in the order of 10 rpm → 30 rpm → 50 rpm → 70 rpm → 90 rpm. After the torque reached its peak, it was kneaded at 90 rpm for 3 minutes to obtain a crosslinked product of the copolymer composition.

Using a 50t electric semi-automatic press (“KMF100-1E” manufactured by Kotaki Co., Ltd.), the crosslinked product of the copolymer composition obtained by the above method was pre-pressed at 190 ° C. for 6 minutes, and then main-pressed for 4 minutes. , A press sheet having a thickness of 2 mm was prepared by cooling and pressing at room temperature for 5 minutes. Using the crosslinked product and sheet of the obtained copolymer composition, the crosslinked product of the copolymer composition was evaluated by the following method.

The results are shown in Table 2.
<MFR>
The obtained copolymer composition was measured at 230 ° C. and a load of 10 kg according to ASTM D 1238.
<Hardness>
The obtained 2 mm-thick sheets were stacked to make a thickness of 12 mm, and the hardness (type A durometer) was measured according to JIS K6253.
<Tensile test>
Using the obtained sheet, a tensile test was performed under the conditions of a measurement temperature of 23 ° C. and a tensile speed of 500 mm / min according to JIS K6251, and the tensile stress (M100), the tensile strength during cutting (TB), and the elongation during cutting (EB). ) Was measured.

<Compressed permanent distortion (sheet CS)>
The obtained 2 mm sheets were stacked to make a thickness of 12 mm, and the compression set after 22 hours of treatment was measured at a predetermined temperature according to JIS K6262: 2013.
<Oil resistance (weight change rate)>
Using the obtained sheet, according to JIS K6258, using liquid paraffin (soft) (Nacalai Tesque Co., Ltd. code number: 26132-35) as a test lubricating oil, the rate of change in weight after treatment at a predetermined temperature and time. Was measured.
<Oil resistance (volume change rate)>
Using the obtained sheet, the volume change rate after treatment was measured at a predetermined temperature and time using IRM903 as a test lubricating oil according to JIS K6258.

[Comparative Example 1]
The same procedure as in Example 1 was carried out except that the above-mentioned copolymer (E-1) was used instead of the copolymer (A-1) used in Example 1, and the copolymer composition and the copolymer composition were carried out. A crosslinked product of the product was obtained. The physical properties of the crosslinked product of the obtained copolymer composition were measured by the method described above. The results are shown in Table 2.

The ethylene / α-olefin / vinylnorbornene copolymer composition according to the present invention can obtain a molded product having good fluidity, good compression set, and excellent oil resistance. In particular, automobile parts used in places where they come into contact with lubricating oil or grease, such as hoses such as automobile hoses (water hoses, brake reservoir hoses, radiator hoses, air hoses), glass run channels, color skin materials, rack and pinions. It can be suitably used for pinion boots, skin materials and the like.

C Polymerization reactor D phase separator E hopper F pump G heat exchanger H heat exchanger I heat exchanger J heat exchanger K heat exchanger

Claims (11)

100 parts by mass of ethylene / α-olefin / vinylnorbornene copolymer (A) and 10 to 300 parts of crystalline olefin polymer (B) containing ethylene, α-olefin having 3 or more carbon atoms, and vinylnorbornene as constituent units. An ethylene / α-olefin / vinylnorbornene copolymer composition, which comprises a part by mass. The ethylene / α-olefin / vinylnorbornene copolymer according to claim 1, wherein the ethylene / α-olefin / vinylnorbornene copolymer (A) satisfies the following conditions (i) to (vii). Combined composition:
(I) The molar ratio [(a1) / (a2)] of the structural unit derived from ethylene (a1) to the structural unit derived from α-olefin (a2) is 40/60 to 99.9 / 0. 1;
(Ii) The weight fraction of the structural unit derived from vinyl norbornene (a3) is 0.07% by weight to 10% by weight in 100% by weight of the copolymer (A);
(Iii) The ratio (molecular weight distribution; Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 8 to 30;
(Iv) The number average molecular weight (Mn) is 30,000 or less; The ethylene / α-olefin / vinylnorbornene copolymer composition according to claim 1 or 2, wherein the crystalline olefin polymer (B) is a propylene (co) polymer. A crosslinked product of the ethylene / α-olefin / vinylnorbornene copolymer composition according to any one of claims 1 to 3. The crosslinked product according to claim 4, wherein the crosslinked product is crosslinked with an organic peroxide. A claim, which comprises dynamically cross-linking an α-olefin / vinylnorbornene copolymer (A) having ethylene and 3 or more carbon atoms and a crystalline olefin polymer (B) in the presence of an organic peroxide. 5. The method for producing a crosslinked product according to 5. A molded product containing the crosslinked product according to claim 4 or 5. An automobile part including the crosslinked product according to claim 4 or 5. An automobile skin material containing the crosslinked product according to claim 4 or 5. An automobile hose comprising the crosslinked product according to claim 4 or 5. Automotive boots comprising the crosslinked product of claim 4 or 5.

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