JPH09132700A - Thermoplastic composition and molded article thereof - Google Patents

Abstract

(57) [PROBLEMS] To provide a thermoplastic composition excellent in flexibility and rubber elasticity (compression set) and having good oil resistance, heat resistance, mechanical strength and impact resistance, and a molded article thereof. SOLUTION: A thermoplastic composition comprising the following component (A) and component (B) and a molded product obtained by molding the same. (A) Polyester elastomer 30 to 98% by weight (B) Olefin elastomer 100 parts by weight, hydroxyl group-containing α, β-unsaturated carboxylic acid ester 0.01 to 20 parts by weight, and other vinyl monomers 0 Modified olefin elastomer obtained by subjecting 50 to 50 parts by weight to a graft copolymerization step 70 to 2% by weight

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic composition which is excellent in flexibility and rubber elasticity (compression set) and has good oil resistance, heat resistance, mechanical strength and impact resistance, and a molded product thereof. is there.

[0002]

2. Description of the Related Art Polyester elastomers have been mainly used for functional parts of automobiles because they are excellent in heat resistance, oil resistance, mechanical strength and impact resistance. However, since polyester-based elastomers are inferior in flexibility and rubber elasticity (compression set), applications requiring flexibility, fields requiring rubber elasticity (compression set),
For example, it could not be used as a substitute for vulcanized rubber. Also, although olefin-based thermoplastic elastomers and styrene-based thermoplastic elastomers have excellent flexibility and rubber elasticity (compression set), they are inferior in oil resistance and heat resistance, so they are used in all applications where vulcanized rubber is used. Could not be replaced.

However, recently, due to problems of process rationalization and recycling, substitution of vulcanized rubber with a thermoplastic elastomer has been required more than ever before. As an attempt to improve the rubber elasticity of a polyester-based elastomer, a method of adding another elastomer having excellent flexibility and rubber elasticity (compression set) is disclosed in JP-B-46-5225 and JP-B-62-91.
No. 36 and JP-A-1-193352. However, all of the methods have improved flexibility and rubber elasticity (compression set), but are poor in compatibility and do not have a uniform and stable dispersion structure, which is a characteristic of polyester elastomers. There was a problem that oil resistance and mechanical strength were reduced.

[0004]

DISCLOSURE OF THE INVENTION The present invention uses a modified olefin elastomer having improved compatibility with a polyester elastomer, and thus has a stable dispersion structure which cannot be achieved by the prior art. An object of the present invention is to provide a thermoplastic composition excellent in flexibility and rubber elasticity (compression set) and having good oil resistance, heat resistance and impact resistance, and a molded article thereof.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a specific hydroxyl group-modified olefin elastomer exhibits extremely good affinity with a polyester elastomer. Find out,
The present invention has been completed. That is, the present invention is a thermoplastic composition comprising the following component (A) and component (B) and a molded product obtained by molding the same. (A) Polyester elastomer 30 to 98% by weight (B) Olefin elastomer 100 parts by weight, hydroxyl group-containing α, β-unsaturated carboxylic acid ester 0.01 to 20 parts by weight, and other vinyl monomers 0 Modified olefin elastomer obtained by subjecting 50 to 50 parts by weight to a graft copolymerization step 70 to 2% by weight

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION

[I] Composition The thermoplastic composition of the present invention comprises a component (A) and a component (B).
And has a flexural modulus of 10 according to JIS-K7203.
00 MPa or less, preferably 500 MPa or less, particularly preferably in the range of 1 to 500 MPa, and JIS
The JIS-A hardness according to -K6301 is preferably 30 or more, preferably 40 or more, and particularly preferably 50 to 100. If the flexural modulus exceeds the above range,
When the JIS-A hardness is less than the above range, the impact resistance is inferior.
It becomes inferior in moldability (release property).

(1) Compounding Material Component (A): Polyester Elastomer The polyester elastomer of the present invention is JIS-K7.
The flexural modulus according to 203 is 1000 MPa or less, preferably 0 to 600 MPa, particularly preferably 10 to 600 MP.
The range of a is preferable. Such polyester-based elastomers include aromatic polyester as a hard component,
Examples thereof include a polyester polyether block copolymer using an aliphatic polyether as a soft component, an aromatic polyester as a hard component, and a polyester polyester block copolymer using an aliphatic polyester as a soft component.

(A) Polyester polyether block copolymer The polyester polyether block copolymer comprises an aliphatic and / or alicyclic diol having 2 to 12 carbon atoms, an aromatic dicarboxylic acid or its alkyl ester, and a weight. Polyalkylene ether glycol having an average molecular weight of 400 to 6000 is used as a raw material, and an oligomer obtained by an esterification reaction or a transesterification reaction is polycondensed.

As the aliphatic and / or alicyclic diol having 2 to 12 carbon atoms used in the present invention, those known as raw materials for polyester, particularly polyester elastomer can be used. Examples thereof include ethylene glycol and propylene. Glycol, trimethylene glycol,
Examples thereof include 1,4-butanediol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol, and preferably 1,4-butanediol, ethylene glycol, and particularly preferably 1,4-butanediol. It is used as a component, and one kind or two or more kinds can be used.

As the aromatic dicarboxylic acid, those known as raw materials for polyesters, particularly polyester elastomers can be used, and terephthalic acid, isophthalic acid,
Examples thereof include phthalic acid and 2,6-naphthalenedicarboxylic acid, preferably terephthalic acid and 2,6-naphthalenedicarboxylic acid, particularly preferably those containing terephthalic acid as a main component. The above may be used in combination. Examples of the alkyl ester of an aromatic dicarboxylic acid include dimethyl esters such as dimethyl terephthalate, dimethyl isophthalate, dimethyl phthalate and 2,6-dimethyl naphthalate, and preferably dimethyl terephthalate and 2,6-dimethyl naphthalate. Yes, particularly preferred is dimethyl terephthalate, which may be used in combination of two or more. Also,
In addition to the above, trifunctional triols, other diols and other dicarboxylic acids and their esters may be copolymerized in small amounts, and further, aliphatic dicarboxylic acids such as adipic acid or alicyclic dicarboxylic acids, or alkyls thereof. Esters and the like may also be used as a copolymerization component.

As the polyalkylene ether glycol, those having a weight average molecular weight of 400 to 6000 are used, but those having a weight average molecular weight of preferably 500 to 4,000, particularly preferably 600 to 3,000 are used. When the weight average molecular weight is less than 400, the block property of the copolymer is insufficient, and when the weight average molecular weight exceeds 6000, the physical properties of the polymer deteriorate due to phase separation in the system. Here, as the polyalkylene ether glycol, polyethylene glycol, poly (1,2 and 1,3 propylene ether)
Glycol, polytetramethylene ether glycol,
Examples thereof include polyhexamethylene ether glycol, a block or random copolymer of ethylene oxide and propylene oxide, and a block or random copolymer of ethylene oxide and tetrahydrofuran. Particularly preferred is polytetramethylene ether glycol. The content of the polyalkylene ether glycol is preferably 5 to 95% by weight, more preferably 10 to 85% by weight, and particularly preferably 20 to 80% by weight, based on the resulting block copolymer. desirable. If the content is more than 95% by weight, it is difficult to obtain a polymer by condensation polymerization.

(B) Polyester Polyester Block Copolymer Further, in the polyester polyester block copolymer of the present invention, an aliphatic or alicyclic dicarboxylic acid is used instead of the polyalkylene ether glycol having a weight average molecular weight of 400 to 6000. And a polyester oligomer condensed from an aliphatic diol and an aliphatic lactone or an aliphatic monoolcarboxylic acid, and the above-mentioned aliphatic and / or alicyclic diol having 2 to 12 carbon atoms and an aromatic dicarboxylic acid, or An oligomer obtained by an esterification reaction or a transesterification reaction is polycondensed using the alkyl ester as a raw material.

As examples of 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid,
Alicyclic dicarboxylic acids such as dicyclohexyl-4,4'-dicarboxylic acid or succinic acid, oxalic acid, adipic acid,
Examples include polyester oligomers having a structure in which one or more aliphatic dicarboxylic acids such as sebacic acid and one or more diols such as ethylene glycol, propylene glycol, tetramethylene glycol, and pentamethylene glycol are condensed. Polycaprolactone-based polyester oligomers synthesized from ε-caprolactone, ω-oxycaproic acid and the like can be mentioned.

(C) Method for producing polyester elastomer The esterification, transesterification and polycondensation reaction in the present invention can be carried out according to a conventional method. As the catalyst in these reactions, one or two or more of known catalysts such as alcoholates such as tin, titanium, zinc and manganese, chlorides and oxides can be used, respectively. Catalysts, especially tetrabutyl titanate, are desirable. Phosphoric acid, phosphorous acid, hypophosphorous acid, or a metal salt thereof may be added as an auxiliary agent. In particular, it is preferable to add an alkali metal hypophosphite since the content of terminal carboxyl groups is reduced and the hydrolysis resistance is improved.

Examples of the alkali metal hypophosphite include sodium hypophosphite, potassium hypophosphite, lithium hypophosphite and the like, and sodium hypophosphite is particularly desirable. The addition amount of the alkali metal hypophosphite is 1 to 1000 ppm, preferably 3 to 200 ppm, and more preferably 5 to 80 ppm, relative to the polymer produced. If it is less than 1 ppm, the effect of the addition cannot be sufficiently obtained, and if it is more than 1000 ppm, the effect is not changed but the polycondensation reaction is inhibited, which is not preferable. As the addition method, the alkali metal hypophosphite may be added to the molten polymer in any state of solution, slurry and solid, and the addition time is preferably at least before the completion of the polycondensation reaction, that is, the ester. It may be added at any time between before the chemical reaction or before the transesterification reaction and before the end of the polycondensation reaction. In particular, it is preferable to add in the form of a slurry immediately before the start of the polycondensation under reduced pressure, since the decrease in polymerizability is small.

Further, other additives may be present in the reaction step. For example, in addition to a hindered phenol-based oxidation stabilizer, a hindered amine-based oxidation stabilizer, a phosphorus-based oxidation stabilizer, a sulfur-based oxidation stabilizer, and a triazole-based light stabilizer, other known additives are used. In particular, in the present invention, 0.01 to 1% by weight of the hindered phenol-based oxidation stabilizer is more preferably added to the polymer from the viewpoint of the effect. The esterification or transesterification reaction is usually performed at 120 to 250 ° C., preferably 150 to 230 ° C., and the melt polycondensation reaction is generally performed at 200 to 280 ° C. for 2 to 6 hours under a reduced pressure of 10 torr or less. Normal,
The polymer obtained by melt polymerization is maintained at a temperature equal to or higher than the melting point, and is sequentially discharged from the reactor and pelletized.
The pellets obtained here may be further subjected to solid-phase polymerization, if necessary.

As such a polyester-polyether copolymer, a commercially available polymer "Perprene P" is used.
(Toyobo Co., Ltd. product name), "Hytrel" (Toray DuPont product name), "Low Mod" (Japan GE Plastics product name), "Nichigo Polyester" (Nippon Gosei Chemical Co., Ltd. product name) , Teijin Polyester Elastomer (trade name, manufactured by Teijin Ltd.) and the like, and polyester polyester block copolymers include commercially available polymer "Perprene S" (trade name, manufactured by Toyobo Co., Ltd.).

Component (B): Modified Olefin-based Elastomer The modified olefin-based elastomer of the present invention comprises α and β having a hydroxyl group in 100 parts by weight of the olefin-based elastomer.
-Graft copolymerization of 0.01 to 20 parts by weight of unsaturated carboxylic acid ester, preferably 0.05 to 10 parts by weight and 0 to 50 parts by weight of other vinyl monomers, preferably 0.01 to 20 parts by weight. It is obtained by subjecting to a process. The olefin elastomer used is JIS-at room temperature.
The flexural modulus according to K7203 is 500 MPa or less, preferably 300 MPa or less, and particularly preferably 100 MPa.
Below, a glass transition temperature is -10 degreeC or less.

The olefin elastomers include homopolymers of olefins such as polybutadiene, polyisoprene and polyisobutylene; ethylene / propylene copolymer rubber (EPM); non-conjugated dienes such as 5-ethylidene norbornene and 5-methyl norbornene. Ethylene-propylene-non-conjugated diene copolymer rubber (EPD) using 5-vinyl norbornene, dicyclopentadiene, etc.
M), ethylene / butene copolymer rubber (EBM), ethylene / propylene / butene copolymer rubber, ethylene / hexene copolymer, ethylene / octene copolymer and other olefin copolymer rubber; ethylene-butadiene copolymer Copolymers of ethylene and diene such as polymers, ethylene-isoprene copolymers, ethylene-chloroprene copolymers; ethylene-vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl acrylate copolymers Examples thereof include copolymers of ethylene and organic acid esters such as polymers.

These copolymers or copolymer rubbers may be random copolymers, block copolymers, graft copolymers or alternating copolymers. These elastic polymers may be used not only as a single component but also as a combination of a plurality of components. Among these, ethylene / propylene / non-conjugated diene copolymers using ethylene / propylene copolymer rubber (EPM) and non-conjugated diene such as 5-ethylidene norbornene, 5-methyl norbornene, 5-vinyl norbornene and dicyclopentadiene Polymer rubber (EPD
M), ethylene-butene copolymer rubber (EBM), ethylene-propylene-butene copolymer rubber, ethylene-hexene copolymer, ethylene-octene copolymer and other olefin-based copolymer rubbers and ethylene-vinyl acetate Copolymer, ethylene-ethyl acrylate copolymer, ethylene-
A copolymer of ethylene and an organic acid ester such as a methyl acrylate copolymer is preferable, and an ethylene / propylene copolymer rubber (EPM), a non-conjugated diene, 5-ethylidene norbornene, 5-methyl norbornene, 5-vinyl is used. Ethylene / propylene / non-conjugated diene copolymer rubber using norbornene, dicyclopentadiene, etc. (EP
DM), ethylene / butene copolymer rubber (EBM), ethylene / propylene / butene copolymer rubber, ethylene /
Olefin-based copolymer rubbers such as hexene copolymer and ethylene / octene copolymer are particularly preferable. The Mooney viscosity (M
L _{1 + 4} (100 ° C)) is 10 to 400, preferably 15
~ 350. When the Mooney viscosity exceeds the above range, the molding appearance is poor, and when it is less than the above range, the rubber elasticity is poor.

Examples of the α, β-unsaturated carboxylic acid ester having a hydroxyl group for modifying the olefin elastomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2,3-. Dihydroxypropyl (meth) acrylate, 2-hydroxymethyl-3-hydroxypropyl (meth) acrylate, 2,2-dihydroxymethyl-
(Meth) such as 3-hydroxypropyl (meth) acrylate, (meth) acrylic acid ester of ethylene glycol or propylene glycol having 4 to 40 carbon atoms
Acrylic esters, bis (2-hydroxyethyl)
Fumarate, bis (2-hydroxypropyl) fumarate, bis (2,3-dihydroxypropyl) fumarate, bis (2-hydroxymethyl-3-hydroxypropyl) fumarate, ethylene glycol or propylene glycol fumarate having 4 to 40 carbon atoms Examples include fumaric acid esters such as acid esters, and similar maleic acid esters. As the fumaric acid and maleic acid esters, not only those in which two carboxyl groups are both esterified with a hydroxyalkyl group as described above, but also those in which only one is esterified can be exemplified as similar monomers. Also, (meth) acrylamides such as N-methylol (meth) acrylamide can be used. However, (meth) acrylate described here means acrylate and methacrylate, and
Acrylic acid means acrylic acid and methacrylic acid,
(Meth) acrylamide means acrylamide and methacrylamide. Among these, 2
-Hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and (meth) acrylic acid ester of ethylene glycol or propylene glycol having 4 to 40 carbon atoms are preferable.

These monomers are not only used alone but
Multiple combinations may be used. Α, β with this hydroxyl group
-In order to increase the grafting efficiency of the unsaturated carboxylic acid ester, it is useful to use another vinyl-based monomer in combination. Such other vinyl-based monomers include styrene and α
-Methylstyrene, α-methoxystyrene, methylstyrene, dimethylstyrene, 2,4,6-trimethylstyrene, chlorostyrene, dichlorostyrene, bromostyrene, nitrostyrene, chloromethylstyrene, cyanostyrene, t-butylstyrene, vinylnaphthalene. Aromatic vinyl monomers such as ethyl (meth) acrylate,
(Meth) acrylic acid ester monomers such as methyl (meth) acrylate, propyl (meth) acrylate, octyl (meth) acrylate; N-methyl (meth) acrylamide, N-methylol (meth) acrylamide, etc. (Meth) acrylamide-based monomers; cyanovinyl-based monomers such as acrylonitrile and methacrylonitrile; vinyl ester-based monomers such as vinyl acetate; methyl vinyl ether,
Examples thereof include vinyl ether monomers such as ethyl vinyl ether and butyl vinyl ether; and heterocycle-containing vinyl compounds such as vinyl imidazole, vinyl oxazoline, vinyl pyridine and vinyl pyrrolidone. These monomers may be used alone or in combination of two or more. Among these, styrene, α-methylstyrene,
When styrene-based monomers such as methylstyrene are used in an amount of 0 to 50 parts by weight, preferably 0.01 to 20 parts by weight, based on 100 parts by weight of the olefin elastomer, the component (A) is used.
The compatibility with is further improved.

The method for modifying the olefin-based elastomer with the above-mentioned α, β-unsaturated carboxylic acid ester having a hydroxyl group and another vinyl-based monomer is not particularly limited. β
-A method in which an unsaturated carboxylic acid ester and another vinyl-based monomer are allowed to coexist and reacted in the presence or absence of a radical generator such as an organic peroxide, a method of irradiating ultraviolet rays or radiation, oxygen or There is a method of contacting with ozone.

As the radical generator, t-butyl hydroperoxide, cumene hydroperoxide, 2,5-
Dimethylhexane-2,5-dihydroperoxide, benzoyl peroxide, dicumyl peroxide, 1,3
-Organic and inorganic peroxides such as bis (t-butylperoxy-isopropyl) benzene, t-butylperoxybenzoate, dibutyl peroxide, methyl ethyl ketone peroxide, potassium peroxide and hydrogen peroxide, 2,
2'-azobisisobutyronitrile, 2,2'-azobis (isobutyramide) dihalide, 2,2'-azo [2-methyl-N- (2-hydroxyethyl) propionamide], azodi-t-butane An azo compound such as, a carbon radical generator such as dicumyl, and the like can be used. These radical generators can be appropriately selected in relation to the modifier and the reaction form. Further, two or more kinds can be used in combination.

The amount of radical generator used is in the range of 0 to 30 parts by weight, preferably 0 to 10 parts by weight, based on 100 parts by weight of the olefin elastomer. The temperature of the graft copolymerization is usually 30 to 350 ° C., preferably 50.
To 300 ° C., and the modification reaction time is 50 hours or less, preferably 0.5 minutes to 24 hours. The graft copolymerization reaction may be carried out in any of a solution state, a molten state and a suspension state. Further, in the case of melt modification by an extruder or the like, for the purpose of improving reaction efficiency, for example, an organic solvent such as xylene, a chain transfer agent, or the like may be added, or kneading under reduced pressure to remove unreacted components or the like. it can.

The content of the α, β-unsaturated carboxylic acid ester having a hydroxyl group introduced into the olefin elastomer is 100 parts by weight of the olefin elastomer.
It is in the range of 0.01 to 20 parts by weight, preferably 0.05 to 10 parts by weight. If the content of the α, β-unsaturated carboxylic acid ester having a hydroxyl group is less than 0.01 parts by weight, the effect of improving the compatibility is small, and if it exceeds 20 parts by weight, there is a problem in moldability due to gelation or the like. The appearance of the molded product may deteriorate, which is not preferable.

The content of the other vinyl-based monomer to be introduced into the olefin-based elastomer depends on the olefin-based elastomer 1
0 to 50 parts by weight, preferably 0.
01 to 20 parts by weight. Even if the other vinyl-based monomer is not used in combination, the compatibility improving effect is observed to some extent, but the compatibility is further improved by the combined use. Also, if it exceeds 50 parts by weight, the appearance of the molded product may deteriorate,
The mechanical strength may decrease, which is not preferable.

(2) Additional compounding material (optional component) The thermoplastic composition of the present invention may contain a component other than the above component (A) and component (B). For example, a part of the modified olefin elastomer of the component (B) may be replaced with an unmodified olefin elastomer. As the unmodified olefin-based elastomer, the above-mentioned olefin-based elastomer may be heat-treated in the presence of an organic peroxide and crosslinked mainly by radicals. Furthermore, polycarbonate, polyphenylene ether, polyamide, etc. may be contained in the resin composition within the range not impairing the object of the present invention. Further, in addition to the above, arbitrary compounding ingredients can be compounded according to various purposes.

Specifically, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a neutralizing agent, a lubricant, an antifogging agent, an antiblocking agent, a slip agent, a crosslinking agent, a crosslinking aid, and a colorant. Various additives such as flame retardants, dispersants and antistatic agents can be added. Of these, it is particularly important to add an antioxidant, and at least one of various antioxidants such as phenol-based, phosphite-based, and thioether-based antioxidants can be used.

For the purpose of polymerizing the polyester elastomer, bifunctional compounds such as bisoxazoline compounds and diepoxy compounds and other polyfunctional compounds, monophosphites such as triphenylphosphite and bis (2,6) -Di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and other phosphite esters exemplified by diphosphites are effective, and alkali metal salts such as anhydrous potassium carbonate are used as catalysts. It can also be added. Further, additional compounding materials such as various thermoplastic resins, various elastomers, various plasticizers, etc. can be compounded within a range that does not significantly impair the effects of the present invention.

Examples of various thermoplastic resins include propylene-based polymers such as propylene homopolymer, propylene / ethylene block copolymer and propylene / ethylene random copolymer, low density polyethylene (branched ethylene polymer), medium density, Ethylene polymers such as high density polyethylene (linear ethylene polymer), ethylene and unsaturated compounds such as ethylene / unsaturated carboxylic acid copolymers or their anhydrides (acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid) Olefin resins such as acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, norbornene-5,6-dicarboxylic acid, and their copolymers; styrene homopolymers, acrylonitrile / styrene resins, acrylic Nitrile, butadiene, styrene resin, etc. Styrene resins. Among these, the following component (C) and component (D) are preferable.

Component (C): Hydrocarbon-based rubber softening agent The hydrocarbon-based rubber softening agent used as an additional component in the thermoplastic composition of the present invention has a weight average molecular weight of 300 to 2,000, preferably. Is 500-1,50
0 can be mentioned. Such a hydrocarbon-based rubber softening agent is a mixture of three aromatic ring, naphthene ring and paraffin ring, and the paraffin chain carbon number is 50% by weight or more of the total carbon. It is called a system oil and has a naphthene ring carbon number of 30 to 45.
Those having a weight% are called naphthenic oils, and those having an aromatic carbon number of more than 30% by weight are called aromatic oils. Among them, it is preferable to use paraffin oil from the viewpoint of weather resistance.

The paraffinic oil used in the present invention has a kinematic viscosity at 40 ° C. of 20 to 800 cSt (centistokes), preferably 50 to 600 cSt, and a pour point of 0.
−40 ° C., preferably 0 to −30 ° C., and a flash point (C
OC) is from 200 to 400C, preferably from 250 to 350.
° C oil is preferably used. The hydrocarbon-based softening agent for rubber is 0 to 200 parts by weight, preferably 0.1 to 100 parts by weight, particularly preferably 1 to 50 parts by weight, based on 100 parts by weight of the total of the components (A) and (B). It is preferable to mix them in parts. The hydrocarbon rubber softener is important for adjusting the hardness and the melt fluidity during molding.

Component (D): Elastic Polymer The elastic polymer referred to in the present invention is one having rubber elasticity other than the olefin elastomer described in the component (B), and specifically, styrene butadiene rubber. (SB
R) hydrogenated product; styrene / ethylene / butylene / styrene copolymer (SEBS), styrene / ethylene / propylene / styrene copolymer (SEPS), styrene /
A compound having a main chain of a hydrogenated product of styrene / conjugated diene block copolymer such as a hydrogenated product of isoprene / butylene / styrene block copolymer; an olefin-based thermoplastic elastomer containing the above-mentioned olefin-based copolymer rubber So, as a commercial item, "Thermo Run" manufactured by Mitsubishi Chemical Co., "Milastomer" manufactured by Mitsui Petrochemical Co., Ltd., "Sumitomo TPE" manufactured by Sumitomo Chemical Co., Ltd., "Santoplane" manufactured by AES.
Etc .; A styrene-based thermoplastic elastomer containing a compound having a hydrogenated product of the above-mentioned styrene / conjugated diene block copolymer as a main chain. Commercially available products are "Lavalon" manufactured by Mitsubishi Chemical Co., Ltd. and "Clayton manufactured by Shell Japan Co., Ltd." G ", Kuraray's" Septon "" High Blur ", Asahi Kasei Kogyo's" Tuftec ", Japan Synthetic Rubber" Dyalon ", etc .;
Copolymer (ACM) of acrylic ester and a small amount of monomer for crosslinking, acrylic rubber such as acrylic ester-acrylonitrile polymer rubber (ANM), acrylic ester-butadiene copolymer rubber, ethylene-acrylic rubber Acrylic polymer rubber such as (AEM); diene rubber such as natural rubber, polyisoprene rubber, polybutadiene rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber; butyl rubber;
Nitrile rubber; chloroprene rubber; silicone rubber; fluororubber; urethane rubber; chlorinated soft resins such as soft vinyl chloride resin and chlorinated polyethylene. The composition of the elastic polymer is to impart flexibility, adjust gloss,
It is also important because it improves rubber elasticity. Among these, the hydrogenated product of the styrene / conjugated diene block copolymer is important for controlling the melt fluidity during molding in addition to the above. In particular, by blending a hydrogenated product of a styrene / conjugated diene block copolymer impregnated with a softener for a hydrocarbon rubber, a hydrocarbon-based material can be easily obtained without a batch kneading process such as Banbury or a kneader. Since the compounding amount of the rubber softening agent can be adjusted, the melt fluidity at the time of molding can be easily adjusted. The hydrogenated product of the styrene / conjugated diene block copolymer is a polymer block in which the conjugated diene is butadiene alone, isoprene alone, or a mixture of isoprene and butadiene, and specifically, styrene / butadiene / styrene. Hydrogenated products of block copolymers (hereinafter sometimes simply referred to as "hydrogenated S-B-S"), hydrogenated products of styrene / isoprene / styrene block copolymers (hereinafter simply referred to as "hydrogenated S-BS"). Abbreviated as "IS"), or styrene-isoprene-butadiene-
Examples thereof include hydrogenated products of styrene block copolymers (hereinafter sometimes simply referred to as "hydrogenated S-BI-S").

The hydrogenated products of these styrene / conjugated diene block copolymers have a weight average molecular weight of 50,000-
500,000, preferably 60,000 to 400,0
00, particularly preferably 70,000 to 300,000,
Styrene content is 5 to 50% by weight, preferably 8 to 45
%, Particularly preferably 10 to 40% by weight, 1,2-microstructure less than 20%, preferably less than 15%, hydrogenation rate of 95% or more, preferably 97% or more. is important. Here, the “weight average molecular weight” is a polystyrene equivalent weight average molecular weight measured by gel permeation chromatography (GPC) under the following conditions.

(Conditions) Instrument: 150C ALC / GPC (manufactured by MILLIPORE) Column: AD80M / S (manufactured by Showa Denko KK) 3 solvents: o-dichlorobenzene Temperature: 140 ° C. Flow rate: 1 ml / min Injection amount: 200 μl Concentration : 2 mg / ml (0.2 wt% of antioxidant 2,6-di-t-butyl-p-phenol was added. Concentration was detected by an infrared spectrophotometer MIRAN 1A manufactured by FOXBORO at a wavelength of 3.42 μm. The styrene / conjugated diene block copolymer having a weight average molecular weight of more than 500,000 is inferior in moldability, and a hydrogenated product of less than 50,000 is inferior in rubber elasticity and mechanical strength. It is a thing.

The hydrogenated products of these styrene / conjugated diene block copolymers can be produced, for example, by the method described in JP-B-40-23798, using a lithium catalyst in an inert solvent containing styrene. A conjugated diene block copolymer was synthesized, and then, for example, Japanese Patent Publication No.
No. 2-8704, Japanese Examined Patent Publication No. 43-6636, JP-A-59.
According to the methods described in JP-A-133203 and JP-A-60-79005, hydrogenation in an inert solvent in the presence of a hydrogenation catalyst can be mentioned.
Further, hydrogenated SIS is described in, for example, JP-A-2-1022.
Hydrogenated S-BI-S by the method described in Japanese Patent No. 12
Is synthesized, for example, by the method described in JP-A-3-188114. The elastic polymer is 0 for the total of 100 parts by weight of the component (A) and the component (B).
˜200 parts by weight, preferably 0.1 to 100 parts by weight, particularly preferably 1 to 50 parts by weight.

(2) Blending ratio The blending ratio of each component constituting the thermoplastic composition of the present invention is such that the component (A) is 30 to 98 wt% of the total amount of the component (A) and the component (B), It is preferably 35 to 95% by weight, particularly preferably 40 to 90% by weight. The above component (A)
If the compounding ratio is less than the above range, the resulting thermoplastic composition is inferior in oil resistance, heat resistance and mechanical strength, and if it exceeds the above range, the flexibility and rubber elasticity (compression set) are inferior.

The blending ratio of the component (B) is 70 to 2% by weight of the total amount of the component (A) and the component (B).
Preferably 65 to 5% by weight, particularly preferably 60 to 10
% By weight. When the compounding ratio of the component (B) exceeds the above range, the thermoplastic composition is inferior in oil resistance, heat resistance and mechanical strength, and when less than the above range, the flexibility and rubber elasticity (compression set) are inferior. Will be things.

(3) Compounding method The method for obtaining the thermoplastic composition of the present invention is a melting method,
Although not particularly limited, such as a solution method and a suspension method, a melt-kneading method is practically preferable. As a specific method for melt-kneading, the powdery or granular component (A) and component (B) are added within the range of the above-mentioned mixing ratio, and if necessary, the addition described in the section of the additional compounding material. A uniform blending method using a Henschel mixer, ribbon blender, V-type blender, etc., followed by kneading and blending with a normal kneader such as a Banbury mixer, kneader, roll, multi-screw kneading extruder such as a single-screw or twin-screw extruder. Can be mentioned.

The temperature of the melt-kneading of each component is 100 ° C to 4 ° C.
In the range of 00 ° C, preferably in the range of 150 ° C to 300 ° C,
Particularly preferably, it is in the range of 180 ° C to 280 ° C. Furthermore, the kneading order and method of each component are not particularly limited, and for example, a method of kneading the modified olefin elastomer and the polyester elastomer and, if necessary, additional compounding material components at once, a part or the whole amount. After kneading the modified olefin elastomer and the polyester elastomer, the remaining components including the additional compounding material component are kneaded, the olefin elastomer and the α, β-unsaturated carboxylic acid ester having a hydroxyl group, and other vinyl Any method such as a method of kneading the system monomer, the radical initiator, the polyester-based elastomer and the additional components at once or a method of kneading under reduced pressure may be used. Furthermore, during melt-kneading, an organic solvent such as chlorobenzene, trichlorobenzene, xylene, or tetrakis (2-ethylhexoxy)
It is also possible to add a catalyst such as titanium or dibutyltin oxide.

[II] Molded Product As a method for producing a molded product of the thermoplastic composition of the present invention, a film molding method (T die laminate molding method, etc.),
Calender molding, (co) extrusion molding method, blow molding method, rotational molding, press molding, injection molding method (insert injection molding method, two-color injection molding method, core back injection molding method, sandwich injection molding method, injection press molding method) ) Etc. can be used. The injection molding method is particularly preferable.

In molding, it is important to use a dried material, and the drying temperature is 20 to 150 ° C, preferably 50 to 130 ° C, more preferably 80 to 120 ° C.
It is necessary to carry out the drying at 1 ° C for 1 to 24 hours, preferably 1 to 10 hours, more preferably 1 to 5 hours. Further, it is more effective to carry out the drying under reduced pressure. By drying under reduced pressure, it is possible to lower the drying temperature and shorten the drying time. When molding is performed using a material that does not dry, the surface of the molded product may be roughened or physical properties may be reduced.

The conditions for injection molding are generally 1
Molding temperature of 00 to 300 ° C, preferably 150 to 280 ° C, particularly preferably 200 to 260 ° C, 50 to 1,000
0 kg / cm ² , preferably 100 to 800 kg / cm
Molded at an injection pressure of ² . Further, molded parts other than products such as runners and spools, defective molded products, and the like can be recycled and used.

[III] Application A molded article made of the thermoplastic composition of the present invention can be used as various industrial parts. Specifically, instrument panels, center panels, center console boxes, door trims, pillars, assist grips, steering wheels, automobile interior parts such as airbag covers, automobile exterior parts such as bumpers and malls, rack and pinion boots, suspension boots. Automotive functional parts such as constant velocity joint boots, vacuum cleaner bumpers, remote control switches, home appliances parts such as various rolls of OA equipment and various key tops, underwater products such as underwater glasses, underwater camera covers, various cover parts, hermeticity It can be used for industrial parts with various packings for the purpose of waterproofing, soundproofing, vibrationproofing, etc., curl cord electric wire coatings, electric parts such as belts, hoses, tubes, and sound deadening gears, electronic parts, sports equipment, etc. it can.

[0046]

The present invention will be described in more detail with reference to the following examples. [I] Evaluation method Various evaluations in these examples and comparative examples were performed by the following test methods. However, the measurement samples of (1) to (6) were measured by an in-line screw type injection molding machine (small injection molding machine made by Toshiba Machine Co .; IS90B), injection pressure 500 kg / cm ² , injection temperature 240 ° C., mold temperature 40.
Obtained by lateral punching of 120 mm x 120 mm x 3 mm sheets molded at ° C. (1) JIS-A hardness [-] conforming to JIS-K-6301 (2) Flexural modulus [MPa] conforming to JIS-K-7203 (3) Compression set [%] conforming to JIS-K-6301 Deformation The compression set (70 ° C. × 22 hours) was measured as a measure of recoverability. (4) Tensile strength In accordance with JIS-K-6301 A tensile test was performed as a measure of mechanical strength, and tensile strength at break [MPa] was measured. (5) Izod impact test In accordance with JIS-K-7110 As a measure of impact resistance, Izod impact strength with notch [k
J / m ² ] was measured at -30 ° C. (6) Oil resistance About 2 g cut out from the injection-molded test piece is JI
It was immersed in a glass tube containing S3 oil at 120 ° C. for 72 hours, and the swelling ratio [%] before and after that was measured.

[II] Raw materials Component (A): Polyester elastomer A-1: 60 parts by weight of dimethyl terephthalate, 1,4-
To 31 parts by weight of butanediol and 35 parts by weight of polytetramethylene ether glycol (average weight molecular weight 1000), 200 ppm of tetrabutyl titanate as a catalyst, in terms of metallic titanium, was added to the produced polymer at 150 ° C to 230 ° C. A transesterification reaction is carried out for 3.5 hours, and then a hindered phenol-based oxidation stabilizer [Ciba Geigy Co., Ltd. product,
Brand name: Irganox 1010] 0.18 parts by weight is added and melt polycondensation is performed at 230 to 245 ° C. under reduced pressure of 3 torr or less to obtain a polyester elastomer (polyester polyether block copolymer: density 1.19 g /
cm ³ , Shore-D hardness 52, melt flow rate (M
FR: 245 ° C., 2.16 kg load) 34 g / 10 minutes,
A flexural modulus of 215 MPa) was produced.

Component (B): Modified olefin elastomer B-1: Ethylene / propylene copolymer rubber (manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: EP01, hereinafter referred to as "EPR"; propylene content 22% by weight, Mooney) Viscosity ML _{1 + 4}
(100 ° C) 19, 230 ° C MFR 3.6g / 10
Min, JIS-A hardness 73) 40 g, 2-hydroxyethyl methacrylate 2 g, styrene 2 g and bis (t-butylperoxyisopropyl) benzene 0.06 g, and then a twin-screw extruder (manufactured by Toyo Seiki Seisakusho Ltd., product (Name: Labo Plastomill), the mixture was melt-kneaded at a temperature of 180 ° C. and a screw rotation speed of 180 rpm for 0.5 minutes, and the kneaded product was pulverized to obtain pellets. From the obtained modified olefin elastomer pellets, the content of the constitutional unit based on 2-hydroxyethyl methacrylate determined by the IR method was 1.13% by weight, and the constitutional unit content of styrene was 0.87% by weight. In addition, JIS-K-721
The MFR of the pellets measured at 230 ° C according to
It was 0.44 g / 10 minutes.

In the IR method, 0.3 g of the obtained modified olefin elastomer was dissolved in 30 ml of xylene by heating and then reprecipitated and purified in 250 ml of methanol. Then, the purified modified olefin elastomer is molded into a film by using a press molding machine, and the IR spectrum is measured by infrared spectroscopy, and the absorption at 1,724 cm ⁻¹ derived from carbonyl and 700 derived from an aromatic ring are obtained.
Due to the absorption at cm ^-1 , using the calibration curve prepared in advance, 2
-Quantify hydroxyethyl methacrylate and styrene.

B-2: EPR (manufactured by Nippon Synthetic Rubber Co., Ltd.,
Product name: EP01) 25 g is completely dissolved in 500 ml of chlorobenzene at 110 ° C., and then 7.5 g of 2-hydroxyethyl methacrylate and 7.5 g of styrene are added,
25 g of chlorobenzene with 2 g of benzoyl peroxide
The radical initiator solution dissolved in was added dropwise and reacted for 3 hours. The reaction system is poured into 4 L of methanol to obtain the modified olefin elastomer as a precipitate. The modified olefin elastomer obtained was filtered, washed with methanol, and then dried under reduced pressure at room temperature for purification. In the obtained modified olefin elastomer, the content of the constituent unit based on 2-hydroxyethyl methacrylate was 2.83% by weight, the content of the constituent unit of styrene was 2.68% by weight, and the MFR was 0.
It was 02 g / 10 minutes.

B-3: In B-1, except that 2-hydroxypropyl methacrylate was used instead of 2-hydroxyethyl methacrylate and 0.04 g of bis (t-butylperoxyisopropyl) benzene was used, B-
Prepared as in 1. The content of the constitutional unit based on 2-hydroxypropyl methacrylate in the obtained modified olefin elastomer was 0.43% by weight, the constitutional unit content of styrene was 0.36% by weight, and the MFR was 1.67 g / 1.
It was 0 minutes.

B-4: B-1 was prepared in the same manner as in B-1 except that styrene was not used, and t-butylperoxybenzoate was used instead of bis (t-butylperoxyisopropyl) benzene. . The content of constituent units based on 2-hydroxyethyl methacrylate in the obtained modified olefin elastomer was 0.67% by weight, and MF
R was 0.73 g / 10 minutes.

B-5: EPR (manufactured by Nippon Synthetic Rubber Co., Ltd.,
A maleated EPR obtained by modifying a trade name: EP01) with maleic anhydride (manufactured by Mitsubishi Chemical Corporation, trade name: Modic, maleic anhydride content 1.2% by weight, MFR 1.0 at 190 ° C.)
g / 10 minutes). B-6: Unmodified EPR (manufactured by Japan Synthetic Rubber Co., Ltd., trade name: EP01). B-7: Unmodified ethylene / propylene / non-conjugated diene copolymer rubber (manufactured by Japan Synthetic Rubber Co., Ltd., trade name: EP98;
Non-conjugated diene is 5-ethylidene norbornene, propylene content 28% by weight, 5 parts by weight oil extension, Mooney viscosity ML
_{1 + 4} (100 ° C) 62, JIS-A hardness 59). Component (C): Hydrocarbon rubber softener C-1: Paraffin oil (shown in Table 1).

[0054]

[Table 1]

Component (D): Elastic polymer D-1 to 3: Hydrogenated styrene / conjugated diene block copolymer (shown in Table 2).

[0056]

[Table 2]

Other components: E-1: Propylene resin (shown in Table 3).

[0058]

[Table 3]

[III] Experimental Examples and Comparative Examples Examples 1 to 10 and Comparative Examples 1 to 4 Compounded in the compounding composition (parts by weight) shown in Tables 4 to 6, and the total amount of the compounding composition was 100 parts by weight. Furthermore, 0.2 parts by weight of a phenol-based antioxidant (trade name "Irganox 1010" manufactured by Ciba-Gaiki Co., Ltd.) and a thioether-based antioxidant (trade name "Seanox 412 manufactured by Shiraishi Calcium Co., Ltd."
S ”) 0.2 part by weight was added, and the mixture was melt-kneaded in a twin-screw extruder having a compression ratio L / D = 33 and a cylinder diameter of 45 mm at 240 ° C. to obtain pellets of the thermoplastic composition. The pellet was dried at 100 ° C. for 4 hours, injection-molded as described above to form a sheet, and subjected to the above-described evaluation. The evaluation results are shown in Tables 4-6.

[0060]

[Table 4]

[0061]

[Table 5]

[0062]

[Table 6]

Example 11 During melt kneading, B-7, component (C) and other component (E-1) of the component (B) having the composition shown in Table 5 were added to 100 parts by weight in total. , Phenolic type antioxidant (Ciba-Gaiki product name "Irganox 1010")
0.05 part by weight was added, the temperature was set to 200 ° C., and the mixture was kneaded in Banbury to obtain pellets. This pellet and the remaining components of Table-5, component (A) and component (B), B
-1, 0.2 parts by weight of phenolic antioxidant (trade name "Irganox 1010" manufactured by Ciba-Gaiki), 0.2 part by weight of thioether antioxidant (trade name "Cynox 412S" manufactured by Shiraishi Calcium Co., Ltd.) Added, L / D =
33, 240 ° C with a twin-screw extruder with a cylinder diameter of 45 mm
The temperature was set to 1 to obtain the thermoplastic composition pellets of the present invention. This was injection molded as described above to form a sheet, and the above evaluation was performed. The results are shown in Table-5.

Example 12 At the time of melt-kneading, with respect to the total amount of B-7, component (C) and other component (E-1) of the component (B) having the composition shown in Table-5, 100 parts by weight. , Phenolic type antioxidant (Ciba-Gaiki product name "Irganox 1010")
After adding 0.05 part by weight and setting the temperature to 200 ° C. and kneading in Banbury, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane-3 was further added as a peroxide. (Product name "Kaya Hexa AD")
3 parts by weight, 0.2 parts by weight of divinylbenzene as a crosslinking aid are added, and the heat treatment (crosslinking treatment) is performed by setting the temperature to 220 ° C. with a twin-screw extruder with L / D = 33 and a cylinder diameter of 45 mm. A partially crosslinked composition pellet was obtained. The pellets and the remaining components of Table-5, component (A), component (B) B-1, 0.2 parts by weight of a phenolic antioxidant (trade name "Irganox 1010" manufactured by Ciba-Gay-Key), thioether 0.2 parts by weight of a system antioxidant (trade name “Synox 412S” manufactured by Shiraishi Calcium Co., Ltd.) was added, and the temperature was set to 240 ° C. by a twin-screw extruder having L / D = 33 and a cylinder diameter of 45 mm. The thermoplastic composition pellets of the present invention were obtained. This was injection molded as described above to form a sheet, and the above evaluation was performed. The results are shown in Table-5.

Comparative Example 5 In the melt-kneading, with respect to 100 parts by weight of the total amount of B-7, the component (C) and the other component (E-1) among the components (B) having the composition shown in Table-6. , Phenolic type antioxidant (Ciba-Gaiki product name "Irganox 1010")
0.05 part by weight was added, the temperature was set to 200 ° C., and the mixture was kneaded in Banbury to obtain pellets. The pellets, B-1 which is the remaining component (B) in Table 6 and 0.2 part by weight of a phenolic antioxidant (trade name "Irganox 1010" manufactured by Ciba-Gaikiy Co.) and a thioether antioxidant ( Product name of Shiraishi Calcium Co., Ltd.
2S ") 0.2 part by weight was added, and the temperature was set to 240 ° C with a twin-screw extruder having L / D = 33 and a cylinder diameter of 45 mm to obtain thermoplastic composition pellets of the present invention. This was injection molded as described above to form a sheet, and the above evaluation was performed. The results are shown in Table-6.

Comparative Example 6 Component (B) of the compounding composition shown in Table 6 at the time of melt kneading,
To the total amount of 100 parts by weight of the component (C) and other components (E-1), 0.05 parts by weight of a phenolic antioxidant (trade name "Irganox 1010" manufactured by Ciba-Gaiki Co., Ltd.) was added, and 200 After the temperature was set to ℃ and kneading with Banbury, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane-
3 (trade name "Kaya Hexa AD") was added in an amount of 0.3 part by weight, and 0.2 part by weight of divinylbenzene as a crosslinking aid was added.
The temperature was set to 220 ° C. by a twin-screw extruder having L / D = 33 and a cylinder diameter of 45 mm, and heat treatment (crosslinking treatment) was performed to obtain partially crosslinked composition pellets. This pellet and Table-6
Component (A), which is the remaining component of the product, and a phenolic antioxidant (trade name “IRGANOX 101” manufactured by Ciba-Gaiki)
0 ") and 0.2 parts by weight of a thioether-based antioxidant (trade name" Seanox 412S "manufactured by Shiraishi Calcium Co., Ltd.)
Add 2 parts by weight, L / D = 33, cylinder diameter 45m
A thermoplastic composition pellet of the present invention was obtained by setting the temperature to 240 ° C with a twin-screw extruder of m. This was injection molded as described above to form a sheet, and the above evaluation was performed. The results are shown in Table-6.

[0067]

The thermoplastic composition of the present invention and the molded article thereof are excellent in flexibility and rubber elasticity (compression set), and are also excellent in oil resistance, heat resistance, mechanical strength and impact resistance. ,
It can be used as various industrial parts and is extremely useful industrially.

Claims (6)

[Claims] 1. A thermoplastic composition comprising the following component (A) and component (B). (A) Polyester elastomer 30 to 98% by weight (B) Olefin elastomer 100 parts by weight, hydroxyl group-containing α, β-unsaturated carboxylic acid ester 0.01 to 20 parts by weight, and other vinyl monomers 0 Modified olefin elastomer obtained by subjecting 50 to 50 parts by weight to a graft copolymerization step 70 to 2% by weight 2. The thermoplastic composition according to claim 1, wherein the component (A) is a polyester polyether block copolymer. 3. The component (B) comprises 100 parts by weight of an olefin elastomer, 0.01 to 20 parts by weight of an α, β-unsaturated carboxylic acid ester having a hydroxyl group, and 0.1.
The thermoplastic composition according to claim 1 or 2, which is a modified olefin-based elastomer obtained by subjecting 01 to 20 parts by weight to a graft copolymerization step. 4. The components (A) and (B) further containing the following components (C) and / or components (D):
The thermoplastic composition according to any one of claims 1 to 3. (C) Hydrocarbon-based rubber softening agent (D) Elastic polymer 5. The thermoplastic composition according to claim 4, wherein the component (D) is a hydrogenated product of a styrene / conjugated diene block copolymer. 6. A molded product obtained by molding the thermoplastic composition according to any one of claims 1 to 5.