JP2003026896A - Thermoplastic elastomer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new thermoplastic elastomer composition which has rich flexibility, excellent formability and excellent compression permanent set. SOLUTION: This thermoplastic elastomer composition comprises (A) an isobutylene block copolymer comprising (a) an isobutylene polymer block having a silicone group bound to a hydrolysable group or hydroxyl group at the terminal and (b) a polymer block consisting mainly of an aromatic vinyl compound, and (B) an olefin resin. The composition preferably comprises 100 compound of the component (A) and 10 to 200 pts.wt. of the component (B). The composition is preferably cross-linked, when the components (A) and (B) are melted and kneaded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel thermoplastic elastomer composition having excellent flexibility, moldability, rubber properties, mechanical strength, and compression set properties.

[0002]

2. Description of the Related Art Conventionally, as a polymeric material having elasticity, a rubber such as a natural rubber or a synthetic rubber mixed with a crosslinking agent or a reinforcing agent and crosslinked under high temperature and high pressure is generally used. However, such rubbers require a process of crosslinking and molding for a long time under high temperature and high pressure, and are inferior in processability. Further, since crosslinked rubber does not show thermoplasticity, recycling molding is generally impossible like thermoplastic resins. Therefore, in recent years, various thermoplastic elastomers have been developed that can easily produce molded products by using general-purpose melt molding techniques such as hot press molding, injection molding, and extrusion molding as with ordinary thermoplastic resins. ing. As such a thermoplastic elastomer, various types of polymers such as olefin-based, urethane-based, ester-based, styrene-based, and vinyl chloride-based polymers have been developed and are commercially available. Since they can be easily recycled, they have been used in a wide range of fields such as automobile parts, home electric appliance parts, electric wire coating materials, medical parts, sundries, and footwear in recent years.

Of these, the styrene-based thermoplastic elastomer is rich in flexibility and excellent in rubber elasticity at room temperature. As the styrene-based thermoplastic elastomer,
Styrene-butadiene-styrene block copolymer (S
BS), styrene-isoprene-styrene block copolymer (SIS), and styrene obtained by hydrogenating them.
Ethylene butylene-styrene block copolymer (SEB
S) and styrene-ethylene propylene-styrene block copolymer (SEPS) are known. But,
These block copolymers had insufficient compression set properties.

Among the styrene-based thermoplastic elastomers, isobutylene has excellent flexibility, excellent rubber elasticity at room temperature, and excellent thermal stability, weather resistance, vibration damping property, gas barrier property, and sealing property. There is known an isobutylene-based block copolymer containing a polymer block mainly composed of and a polymer block mainly composed of an aromatic vinyl compound. However, this isobutylene block copolymer also has a problem in compression set.

On the other hand, a technique for compounding a rubber and an organic polymer in order to improve the performance of a thermoplastic elastomer has been known for a long time, and in particular, polyolefin such as PP is
Many studies have been made on a technique for compounding an olefin elastomer such as EPDM or IIR, or a crosslinked body of a styrene elastomer such as SEBS. For example, in the case of an olefin thermoplastic elastomer, a crystalline olefin resin is used. Of cross-linking olefin rubber with olefinic rubber using organic peroxide (Japanese Patent Publication No. 53-2102).
1), technology for cross-linking using phenolic resin (Japanese Patent Publication 5)
8-46138), and a technique for crosslinking by using a hydrosilyl group (JP-A-11-166075, JP-A-11-1811).
72) and the use of special structure isobutylene rubber (JP-A-9-137007).
In both cases, as a rubber component, in the olefin polymer,
EPDM in which double bonds are randomly present as crosslinking points,
Since olefin rubber such as IIR is used, the cross-linking is uneven and it is difficult to reduce the hardness.

[0006]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is not only the thermal stability, weather resistance, vibration damping property and gas barrier property, which are characteristic of the polyisobutylene segment, but also the flexibility. It is intended to provide a thermoplastic elastomer composition which is excellent in moldability and is excellent in molding processability, particularly compression set characteristics.

[0007]

Means for Solving the Problems That is, the present invention is directed to an isobutylene polymer block (a) having a hydrolyzable group or a silicon group bonded to a hydroxyl group at the terminal and a polymer block mainly containing an aromatic vinyl compound. A thermoplastic elastomer composition containing an isobutylene block copolymer (A) containing (b) and an olefin resin (B), and 10 to 100 parts by weight of the isobutylene block copolymer (A). It is preferable to contain 200 parts by weight of the olefin resin (B).

The thermoplastic elastomer composition may be dynamically crosslinked during the melt-kneading of the isobutylene block copolymer (A) and the olefin resin (B). As the composition, as the component (C),
A silanol condensation catalyst can be contained, and a plasticizer can also be contained as the component (D). The plasticizer (D) is 1 per 100 parts by weight of the total amount of (A) and (B).
It is preferable to contain 0 to 300 parts by weight.

The isobutylene block copolymer (A) has a number average molecular weight of 2000 to 100,000, and is a block having at least one hydrolyzable group or a silicon group bonded to a hydroxyl group at the end per molecule. The copolymer is preferable, and as the structure of the isobutylene block copolymer (A), a polymer block (a) mainly containing isobutylene and a polymer block (b) mainly containing an aromatic vinyl compound are used. ) And (b)-(a)-(b)
A triblock copolymer having the structure of is preferable.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The thermoplastic elastomer composition of the present invention is mainly composed of an isobutylene polymer block (a) having a silicon group bonded to a hydrolyzable group or a hydroxyl group at the end and an aromatic vinyl compound. Polymer block (b)
And an olefin resin (B) containing an isobutylene block copolymer (A).

The isobutylene-based block copolymer (A) of the present invention means a polymer block (a) mainly composed of isobutylene, wherein isobutylene is 50% by weight or more, preferably 70% by weight or more, more preferably 90% by weight. A block that occupies the above. In the polymer block mainly composed of isobutylene, the monomer other than isobutylene is not particularly limited as long as it is a cationically polymerizable monomer component, but aromatic vinyls, aliphatic olefins, isoprene, butadiene, divinyl. Examples include dienes such as benzene, allyl ethers, and monomers such as β-pinene. These may be used alone or in combination of two or more.

The polymer block (b) containing an aromatic vinyl compound as a main component of the isobutylene block copolymer (A) means 50% by weight or more of the aromatic vinyl compound,
Preferably 70% by weight or more, more preferably 90% by weight
A block that occupies the above. The monomer other than the aromatic vinyl compound in the polymer block mainly composed of the aromatic vinyl compound is not particularly limited as long as it is a cationically polymerizable monomer, but aliphatic olefins, dienes, allyl Examples of the monomers include ethers and β-pinene. Examples of the aromatic vinyl compound of the polymer block (b) include styrene, α-methylstyrene, β-methylstyrene, p-methylstyrene, t-butylstyrene, monochlorostyrene, dichlorostyrene, methoxystyrene and indene. To be Among the above compounds, styrene, α-methylstyrene, p-methylstyrene and indene are preferable from the viewpoint of cost, physical properties and productivity, and two or more kinds may be selected from them. The monomer other than isobutylene in the polymer block containing an aromatic vinyl compound as a main component is not particularly limited as long as it is a cationically polymerizable monomer component, and may be used alone or in combination with two kinds. You may use it in combination of the above.

There are no particular restrictions on the proportion of the polymer block (a) mainly containing isobutylene and the polymer block (b) mainly containing an aromatic vinyl compound in the isobutylene block copolymer (A). In consideration of the balance between physical properties and processability, the polymer block (a) mainly containing isobutylene is 95 to 20 parts by weight, and the polymer block (b) mainly containing an aromatic vinyl compound is 5 to 80 parts by weight. It is particularly preferable that the polymer block (a) mainly containing isobutylene is 90 to 60 parts by weight, and the polymer block (b) mainly containing an aromatic vinyl compound is 10 to 40 parts by weight.

The preferred structure of the isobutylene block copolymer (A) of the present invention is at least one of the polymer blocks (a) containing isobutylene as a main component from the viewpoint of physical properties and processability of the resulting composition. A structure having at least two polymer blocks (b) mainly containing an aromatic vinyl compound is preferable. Although the structure is not particularly limited, for example, a triblock copolymer formed from (b)-(a)-(b), {(b)-
It is possible to use at least one kind selected from a multi-block copolymer having repeating (a)} units and a star-shaped polymer having a diblock copolymer consisting of (b)-(a) as an arm. . Further, in the isobutylene-based block copolymer (A), in addition to the above structure, a polymer mainly containing isobutylene, a polymer mainly containing an aromatic vinyl compound, and a diamine composed of (a)-(b) At least one kind of block copolymer may be contained. However, from the viewpoint of physical properties and processability, at least one of the polymer blocks (a) mainly containing isobutylene contained in the isobutylene block copolymer (A) and a polymer mainly containing an aromatic vinyl compound. It is preferable that the structure having at least two blocks (b) is 50% by weight or more.

The number average molecular weight of the isobutylene block copolymer (A) is not particularly limited, but it is 1,000 to 5
0,000 is preferable, 2,000 to 100,000
0 is especially good. When the number average molecular weight is less than 1,000, mechanical properties are not sufficiently expressed,
When it exceeds 50,000, the moldability and the like are largely deteriorated.

The term "silicon group having a hydrolyzable group or hydroxyl group bonded to the terminal" means a group having a Si-X bond, where X is a hydrolyzable group or hydroxyl group. Normally,
Si-OH and H-X by hydrolysis reaction of Si-X bond
give.

These silicon groups are well-known functional groups, and a typical example thereof is represented by the general formula (I):-(SiR ¹ _2-b X _b O) _m -SiR ² _3-a X _a (I ] In the formula, each of R ¹ and R ² is an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and 7 to 20 carbon atoms.
Or an aralkyl group of R ³ ₃ SiO— (R ³ has 1 to 1 carbon atoms
20 is a monovalent hydrocarbon group, and three R ^{3 s} may be the same or different) and is a triorganosiloxy group represented by the formula (1) wherein two or more R ¹ or R ² are present. When they do, they may be the same or different. X is a hydrolyzable group or a hydroxyl group, and when two or more are present, they may be the same or different. a is an integer selected from 0 to 3, and b is an integer selected from 0 to 2. However, a + mb ≧ 1
Meet In addition, _b in m (SiR ¹ _2-b X _b O) need not be the same. m is an integer selected from 0 to 19. ] The group represented by these can be mentioned.

The hydrolyzable group in the general formula (I) is not particularly limited and may be a conventionally known hydrolyzable group. Specific examples thereof include a hydrogen atom, an alkoxy group and an acyloxy group. , A ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group, an alkenyloxy group and the like. Among these, an alkoxy group is particularly preferable in terms of mild hydrolyzability and easy handling.

This hydrolyzable group or hydroxyl group can be bonded to one silicon atom in the range of 1 to 3 and (a + m
b) is preferably in the range of 1-5. When two or more hydrolyzable groups or hydroxyl groups are bonded to the reactive silicon group, they may be the same or different.
The number of silicon atoms forming the reactive silicon group may be one or two or more, but in the case of silicon atoms linked by a siloxane bond or the like, it is preferable that the number is 20 or less. Particularly, the reactive silicon group represented by the general formula (II): —SiR ² _3-a X _a (II) (wherein R ² , X and a are the same as described above) is easily available. Therefore, it is preferable.

More specifically, in view of availability, an alkoxysilyl group or an alkylalkoxy group is preferable,
From the viewpoint of reactivity, a trimethoxysilyl group, a methyldimethoxysilyl group, a triethoxysilyl group, and a methyldiethoxysilyl group are particularly preferable, and a methyldimethoxysilyl group is more preferable from the viewpoint of the balance between reactivity and storage stability.

The number of reactive silicon groups is preferably at least one on average per molecule of the isobutylene copolymer,
1.1-5 pieces are more preferable. When the number of reactive silicon groups contained in the molecule is less than 1, the crosslinkability becomes insufficient and it becomes difficult to exhibit good rubber elasticity behavior. The reactive silicon group may be present at the terminal of the isobutylene-based copolymer molecular chain, may be present inside, or may be present at both ends. Especially at least one of the reactive silicon groups
In the case of having one at the end of the molecular chain, the amount of effective network chains of the isobutylene-based copolymer component contained in the finally formed crosslinked product increases, so that a rubbery crosslinked product with high strength and high elongation is obtained. It is preferable from the viewpoint of easy handling. Further, these isobutylene-based copolymers having a reactive silicon group may be used alone or in combination of two or more kinds.

In the case of an isobutylene-based copolymer, it is known that many functional groups can be introduced after polymerization by the inifer method. For example, an alkenyl group (JP-A-63-105005, JP-A-1-105005) 248406, W
O90 / 15081, JP-A-4-288309),
(Meth) acrylic group (JP-A-2-88614, etc.), hydroxyl group (Ivan et al., J. Polymer Sci., P.
polymer Chem. Ed. 18,3177
(1980), JP-A-4-20501, and JP-A-11-3.
02320, JP 2000-119330 A, JP 200 A
0-103810), carbonyl group (JP 2000-
150076, JP-A 2000-169518, etc.) and glycidyl group (US Pat. No. 4,420,99 etc.).

Then, based on the introduced functional group,
Hydrolyzable silicon group (JP-A 63-006041, JP-A 63-6003, JP-A 1-197509, JP-A 4-9
-103606, JP-A-7-53882, etc.) can be easily synthesized.

The isobutylene type copolymer having a reactive silicon group in the molecule is copolymerized by adding vinylsilanes or allylsilanes having a reactive silicon group to a monomer mainly containing isobutylene. Manufactured by Furthermore, the isobutylene-based copolymer having a reactive silicon group at both the inside and the molecular end of the molecule constitutes the main chain during polymerization when producing the isobutylene-based copolymer having a reactive silicon group at the above-mentioned molecular end. It can be produced by copolymerizing vinyl silanes or allyl silanes having a reactive silicon group in addition to the above monomer, and then introducing a reactive silicon group at the terminal.

The olefin resin (B) used in the present invention is ethylene or an α-olefin homopolymer or copolymer containing 50 to 100 mol% of α-olefin having 3 to 20 carbon atoms, High density polyethylene, low density polyethylene, polypropylene, ethylene propylene copolymer, EPR, EPDM, ethylene butene copolymer, ethylene octene copolymer, polyisobutylene, butyl rubber, chlorinated butyl rubber, brominated butyl rubber, physical properties preferably An example is polypropylene.

The compounding amount of the olefin resin (B) is preferably 10 to 200 parts by weight, based on 100 parts by weight of the isobutylene block copolymer of the component (A).
It is more preferably 0 to 100 parts. When the blending amount of the olefin resin (B) exceeds 200 parts by weight, improvement in compression set characteristics tends to be poor. If it is less than 20 parts by weight, moldability tends to be a problem.

The thermoplastic elastomer composition comprising the component (A) isobutylene block copolymer and the olefin resin (B) is preferably dynamically crosslinked during melt kneading.

The crosslinked product formed here includes a product in which either (A) or (B) is independently crosslinked, or a product in which (A) and (B) are simultaneously contained in the crosslinked product and crosslinked. Be done. Of these, it is preferable that (A) alone form a crosslinked product.

In the crosslinkable composition of the present invention, a part or all of the hydrolyzable groups bonded to the silicon group of the isobutylene copolymer as the component (A) are hydrolyzed to form a siloxane bond ( Silanol condensation reaction) produces particularly excellent properties.

To crosslink the component (A) by a silanol condensation reaction, a silanol condensation catalyst [component (C)] can be added to the composition of the present invention. Specific examples of the silanol condensation catalyst include, for example, tin, aluminum, titanium compounds, or amine compounds or salts of amine compounds with carboxylic acids; low molecular weight polyamide resins obtained from excess polyamine and polybasic acid. A reaction product of an excess polyamine and an epoxy compound; a silane coupling agent amine compound having an amino group such as γ-aminopropyltrimethoxysilane and N- (β-aminoethyl) aminopropylmethyldimethoxysilane; Examples thereof include known silanol condensation catalysts such as other silanol condensation catalysts and other acidic catalysts and basic catalysts.

Specific examples of the tetravalent tin condensation catalyst include tetravalent tin carboxylates such as dibutyltin bisacetylacetonate, dibutyltin dialkoxide, dibutyltin dilaurate, dibutyltin maleate and dibutyltin diacetate. Can be given.
Specific examples of the silanol condensation catalyst other than the above-mentioned tetravalent tin condensation catalyst include divalent tin condensation catalysts such as tin octylate; titanate esters such as tetrabutyl titanate and tetrapropyl titanate; aluminum. Aluminum-based condensation catalysts such as trisacetylacetonate, aluminum trisethylacetoacetate, diisopropoxyaluminum ethylacetoacetate; zirconium tetraacetylacetonate; lead octylate; butylamine, octylamine, laurylamine, dibutylamine, monoethanolamine, Diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine, xylylenediamine Min, triethylenediamine, guanidine, diphenylguanidine, 2,4,6-tris (dimethylaminomethyl) phenol, morpholine, N
It is an amine-based condensation catalyst such as -methylmorpholine, 2-ethyl-4-methylimidazole, and 1,8-diazabicyclo (5,4,0) undecene-7 (DBU).

The silanol condensation catalyst can be freely selected according to the use conditions, but a tin compound, particularly a dibutyltin compound is preferable from the viewpoint of storage stability, curing rate and availability. The above silanol condensation catalysts may be used alone or in combination of two or more. The silanol condensation catalyst is an isobutylene-based copolymer (A) 100 having a reactive silicon group from the viewpoint of crosslinking speed and storage stability.
It is preferably used in the range of 0.01 to 50 parts per part. Particularly, it is preferably used in the range of 0.1 to 30 parts, more preferably 0.1 to 5 parts. The composition of the present invention includes
In addition to the isobutylene block copolymer of the component (A), the olefin resin (B) and the silanol condensation catalyst (C), a plasticizer (D) is further added in order to further improve moldability and flexibility. Is preferred.

The plasticizer (D) is not limited within the scope of the present invention, and examples thereof include polybutene, hydrogenated polybutene, hydrogenated α-olefin oligomers, polyvinyl oligomers such as atactic polypropylene; biphenyl, triphenyl. Aromatic oligomers such as; Polyene oligomers such as liquid polybutadiene; Hydrogenated polyene oligomers such as hydrogenated liquid polybutadiene; Paraffin oligomers such as paraffin oil and chlorinated paraffin oil; Naphthene oils such as naphthene oil (cycloparaffin) System) oligomer; dibutyl phthalate, diheptyl phthalate, di (2-ethylhexyl) phthalate, butylbenzyl phthalate, di-n-octyl phthalate, diisononyl phthalate, diisodecyl phthalate, diundecyl phthalate. What phthalates; di (2
-Ethylhexyl) adipate, di-n-octyl adipate, diisononyl adipate, diisodecyl adipate, di (2-ethylhexyl) sebacate, di-2-ethylhexyl tetrahydrophthalate, and the like, non-aromatic dibasic acid esters; trimellitic acid tri-2-ethylhexyl , Aromatic esters such as triisodecyl trimellitate; fatty acid esters such as butyl oleate, methyl acetylricinoleate, pentaerythritol ester; polyalkylene glycol esters such as diethylene glycol benzoate, triethylene glycol dibenzoate; Phosphoric acid esters such as dil phosphate and tributyl phosphate; use of epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil Come. These may be used alone or in combination of two or more. In particular, as the plasticizer (D), it is preferable to use a mineral oil used in the processing of rubber, or a liquid or low molecular weight synthetic softening agent. Examples of the mineral oil include the above-mentioned paraffin-based, naphthene-based, and aromatic high-boiling petroleum components, but paraffin-based and naphthene-based oils that do not inhibit the crosslinking reaction are preferable. The liquid or low molecular weight synthetic softening agent is not particularly limited, and examples thereof include the above-mentioned polybutene, hydrogenated polybutene, liquid polybutadiene, hydrogenated liquid polybutadiene, and poly α-olefins. One or more of these plasticizers (D) can be used. The blending amount of the plasticizer (D) is preferably 10 to 300 parts by weight with respect to 100 parts by weight of the isobutylene block copolymer as the component (A). If the blending amount exceeds 300 parts by weight, mechanical strength is lowered and moldability is problematic.

In the composition of the present invention, in addition to the above-mentioned components (A), (B), (C) and (D), a tackifying resin and a water A silane compound containing a decomposable group, an olefin resin having a silicon group bonded to a hydrolyzable group or a hydroxyl group can be appropriately added. The tackifying resin has an adhesive property, an adhesive property,
It is used to adjust resin compatibility, viscosity control, etc.
It can be freely selected from the commonly used ones according to the purpose. For example, petroleum resin type, phenol type, terpene type, rosin ester type, modified terpene type, hydrogenated terpene type, pinene type, coumarone indene type , Styrene, and hydrogenated products thereof. The amount of the tackifying resin used is determined according to other compounding compositions and target characteristics and is not particularly limited within the usable range, but is 2 to 1000 parts per 100 parts of the total of the components (A) and (B). It is preferable to use in the range of. In particular, it is preferably used in the range of 10 to 100 parts.

The hydrolyzable group-containing silane compound has effects such as improvement in adhesiveness, crosslinkability and storage stability, and can be appropriately used according to the required characteristics. The hydrolyzable group-containing silane compound species is not particularly limited as long as it can be used, for example,
Examples thereof include those having a hydrolyzable group such as a methoxy group, an ethoxy group, a propoxy group and an oxime group. The functional group other than the silyl group present in the hydrolyzable group-containing silane compound is not particularly limited as long as it can be used, vinyl group, methacryl group, acryl group, mercapto group, hydroxyl group, isocyanate group, amino group, Examples thereof include an amide group and a glycidyl group. As more specific examples, ethyl silicate, silicate condensate, vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane,
3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropyltriethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-phenyl-3 -Aminopropyltrimethoxysilane, N- (β-aminoethyl) aminopropylmethyldimethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidylpropyltrimethoxysilane and the like are exemplified. It

The above silane compound was added to 100 parts of the isobutylene-based copolymer (A) having a reactive silicon group,
It is preferably used in the range of 0.01 to 50 parts. In particular, it is preferably used in the range of 0.1 to 30 parts, more preferably 1 to 10 parts.

The above silane compounds may be used alone or in a mixture of two or more kinds. For example, in view of storage stability, silicate, vinyltrimethoxysilane, 3-methacryloxypropyltrisilane. One or more compounds selected from methoxysilane are used, and further, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3
-Aminopropylmethyldiethoxysilane, 3-aminopropyltriethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- (β-aminoethyl) aminopropyl It is also possible to use one or more compounds selected from methyldimethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, and 3-glycidylpropyltrimethoxysilane. An olefin resin having a hydrolyzable group or a silicon group bonded to a hydroxyl group may be added. A graft polymer is produced by the reaction of this component and the isobutylene-based block copolymer of component (A) in the system. As a result, it is expected that the compatibility of the isobutylene block copolymer as the component (A) and the polyolefin resin as the component (B) will be improved. The polyolefin in this component is preferably a polymer having a structure compatible with the olefin resin of component (B), and particularly preferably the same structure as that of component (B). Since polypropylene is preferable as the olefin resin as the component (B), polypropylene is also preferable as the polyolefin in this component. There are some commercially available methods for producing this component (Mitsubishi Chemical, Linklon, etc.), and there is no particular limitation.
-298249, the production method described in JP-A-10-77374 and the like. The composition of the present invention also includes
Furthermore, for example, a styrene-butadiene-styrene block copolymer (S
BS), styrene-isoprene-styrene block copolymer (SIS), and styrene obtained by hydrogenating them.
Ethylene butylene-styrene block copolymer (SEB
S), styrene-ethylene propylene-styrene block copolymer (SEPS), and unmodified SIBS and other elastomers, thermoplastic resins, and other fillers, reinforcing agents, silane coupling agents, and adhesiveness-imparting agents. , Radical crosslinking agents and crosslinking aids, antioxidants (phenolic antioxidants, aromatic amine antioxidants, sulfur hydroperoxide decomposers, phosphorus hydroperoxide decomposers,
Benzotriazole-based UV absorber, salicylate-based UV absorber, benzophenone-based UV absorber, hindered amine-based light stabilizer, nickel-based light stabilizer, etc.), photocurable resin, waxes, flow improver, lubricant, Various additives such as a surfactant, a foaming agent, a flame retardant, and a pigment can be appropriately blended as necessary. The filler used in the present invention is used for the purpose of imparting properties such as hardness, strength, and stretchability, and for cost reduction, and the like, calcium carbonate, clay, talc, silica, alumina, glass fiber, carbon fiber, mica, graphite. , Fume silica, precipitated silica, silicic acid anhydride, carbon black, titanium oxide, magnesium carbonate, quartz, aluminum fine powder, flint powder, zinc dust, wood powder, pulp, cotton chips, asbestos, walnut shell powder, chaff powder , Diatomaceous earth, clay and the like can be used, and flame retardant fillers such as aluminum hydroxide, magnesium hydroxide and ammonium phosphate can be used for imparting flame retardancy. Further, a hygroscopic filler such as zeolite, silica gel, molecular sieve or the like can be used for the purpose of imparting hygroscopicity described later. These fillers may be used alone or in combination of two or more.

Specific examples of the silane coupling agent include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane and γ- ( 2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2
-Aminoethyl) aminopropylmethyldiethoxysilane, γ-ureidopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, N-
Benzyl-γ-aminopropyltrimethoxysilane, N
-Amino group-containing silanes such as vinylbenzyl-γ-aminopropyltriethoxysilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropylmethyldiethoxy. Mercapto group-containing silanes such as silane; γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethyl Epoxy group-containing silanes such as trimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltriethoxysilane; β-carboxyethyltriethoxysilane and β-carboxyethylphenylbis (2
-Methoxyethoxy) silane, N-β- (carboxymethyl) aminoethyl-γ-aminopropyltrimethoxysilane and other carboxysilanes; vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, γ Vinyl type unsaturated group-containing silanes such as acroyloxypropylmethyltriethoxysilane; halogen-containing silanes such as γ-chloropropyltrimethoxysilane; isocyanurate silanes such as tris (trimethoxysilyl) isocyanurate; -Containing isocyanate groups such as isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatepropylmethyldimethoxysilane Silanes and the like. Further, modified derivatives of these, amino-modified silyl polymers, silylated amino polymers, unsaturated aminosilane complexes, blocked isocyanate silanes, phenylamino long-chain alkylsilanes, aminosilylated silicones, silylated polyesters, etc. are also used as silane coupling agents. Can be used.

The above silane coupling agents may be used alone or in combination of two or more. An adhesiveness-imparting agent other than the silane coupling agent can be used in the thermoplastic elastomer composition of the present invention.

Further, a radical crosslinking agent may be shared.
A radical initiator such as organic peroxide is used as the catalyst. The radical initiator is not particularly limited, and examples thereof include di-t-butyl peroxide, 2,
5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexyne, dicumyl peroxide, t
-Butylcumyl peroxide, dialkyl peroxides such as α, α'-bis (t-butylperoxy) isopropylbenzene, benzoyl peroxide, p-chlorobenzoyl peroxide, m-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide,
Diacyl peroxides such as lauroyl peroxide, peroxyesters such as t-butyl perbenzoate, diisopropyl percarbonate, peroxydicarbonates such as di-2-ethylhexyl percarbonate, 1,1-di (t
-Butylperoxy) cyclohexane, 1,1-di (t
Examples thereof include peroxyketals such as -butylperoxy) -3,3,5-trimethylcyclohexane. Of these, 2,5-dimethyl-2,5-di- (tert-) is preferable in terms of odor, coloring and scorch stability.
Butyl peroxy) hexane, 2,5-dimethyl 2,5
-Di- (tert-butylperoxy) hexyne-3 is preferred.

The blending amount of the organic peroxide is preferably in the range of 0.5 to 5 parts by weight with respect to 100 parts by weight of the isobutylene block copolymer at the time of adding the organic peroxide.

The composition of the present invention may contain a cross-linking aid having an ethylenically unsaturated group in the cross-linking treatment with an organic peroxide. The ethylenically unsaturated group, for example, a polyfunctional vinyl monomer such as divinylbenzene, triallyl cyanurate, or ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate,
Examples thereof include polyfunctional methacrylate monomers such as polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, and allyl methacrylate.
These may be used alone or in combination of at least two kinds. With such a compound, a uniform and efficient crosslinking reaction can be expected.

Among them, especially ethylene glycol dimethacrylate and triethylene glycol dimethacrylate are easy to handle and have a peroxide solubilizing effect,
Since it works as a dispersion aid of peroxide, the crosslinking effect by heat treatment is uniform and effective, and a crosslinked thermoplastic elastomer having a well-balanced hardness and rubber elasticity can be obtained, which is preferable. The amount of the above-mentioned crosslinking aid added is 0.5 with respect to 100 parts by weight of the modified isobutylene block copolymer.
The range of up to 10.0 parts by weight is preferred. If the addition amount of the crosslinking aid is less than 0.5 part, the effect as the crosslinking aid is not obtained, and if it exceeds 10 parts by weight, gelation of the crosslinking aid alone may cause deterioration of the physical properties of the dimple. High cost.

Specific examples of the phenolic antioxidant include 2,6-di-t-butylphenol, 2,4-di-t-butylphenol and 2,6-di-t-butyl-4.
-Methylphenol, 2,5-di-t-butylhydroquinone, n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, pentaerythrityl-tetrakis [3- (3,3 5-di-t-butyl-4-hydroxyphenyl) propionate],
2,2'-methylenebis (4-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 4,4'-thiobis (3-methyl-6-t) -Butylphenol) and the like.

Specific examples of the aromatic amine antioxidants include N, N'-diphenyl-p-phenylenediamine and 6-ethoxy-2,2,4-trimethyl-1,2-.
Dihydroquinoline etc. can be illustrated.

Specific examples of the sulfur hydroperoxide decomposer include dilauryl-3,3'-thiodipropionate, ditridecyl-3,3'-thiodipropionate and distearyl-3,3'-thiodipropionate. Pionate etc. can be illustrated.

Specific examples of the phosphorus hydroperoxide decomposer include diphenylisooctyl phosphite,
Examples thereof include triphenyl phosphite.

Specific examples of the benzotriazole type ultraviolet absorber include 2- (3,5-di-t-butyl-2-
Hydroxyphenyl) -5-chlorobenzotriazole, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2-
(3,5-di-t-butyl-2-hydroxyphenyl)
Examples thereof include benzotriazole and 2- (5-methyl-2-hydroxyphenyl) benzotriazole.

Specific examples of the salicylate-based ultraviolet absorber include 4-t-butylphenyl salicylate and 2,
4-di-t-butylphenyl-3,5'-di-t-butyl-4'-hydroxybenzoate etc. can be illustrated.

Specific examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone and 2
Examples include -hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone and 2-hydroxy-4-benzyloxybenzophenone.

Specific examples of the hindered amine light stabilizer include bis (2,2,6,6, -tetramethyl-4).
-Piperidyl) sebacate, bis (1,2,2,6)
6, -pentamethyl-4-piperidyl) sebacate, 1
-{2- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl} -4-
[3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2
Examples include 6,6, -tetramethylpiperidine and the like.

Specific examples of the nickel-based light stabilizer include nickel dibutyldithiocarbamate and [2,2].
'-Thiobis (4-t-octylphenolate)]-2
-Ethylhexylamine nickel (II), [2,2
'-Thiobis (4-t-octylphenolate)]-n
-Butylamine nickel (II) etc. can be illustrated.

These antioxidants may be used alone or in combination of two or more. When used in combination, it may function more effectively than when used alone.

The most preferred composition of the thermoplastic elastomer composition of the present invention mainly comprises an isobutylene polymer block (a) having a silicon group bonded to a hydrolyzable group or a hydroxyl group at the end and an aromatic vinyl compound. 20 to 100 parts by weight of the olefin resin (B) and 10 parts by weight of the plasticizer (D) based on 100 parts by weight of the crosslinked product of the isobutylene block copolymer (A) containing the polymer block (b).
~ 300 parts by weight.

The method for producing the thermoplastic elastomer composition of the present invention is not particularly limited, and the isobutylene-based polymer block (a) having a hydrolyzable group or a silicon group bonded to a hydroxyl group at the terminal and an aromatic vinyl-based polymer block. Any method as long as the isobutylene block copolymer (A) containing the polymer block (b) containing a compound as a main component, the olefin resin (B), and optionally the above-mentioned components can be uniformly mixed. Can also be adopted.

When the component (A) and the olefin resin (B) are melt-mixed, the component (A) and / or the olefin resin (B) are dynamically crosslinked to produce the thermoplastic elastomer composition of the present invention. In that case, it can be preferably carried out by the method exemplified below.

For example, a closed type kneading device or a batch type kneading device such as a Labo Plastomill, a Brabender, a Banbury mixer, a kneader, a roll, a single screw extruder,
It is produced using a continuous melt-kneading device such as a twin-screw extruder or a molding machine such as extrusion molding, injection molding, compression molding, etc., but all components are mixed in advance and melt-kneaded until uniform. Then, it is possible to employ a method in which water is added thereto and the melt-kneading is stopped after the crosslinking reaction has sufficiently proceeded. A temperature of 140 to 210 ° C. is preferable for carrying out the above-mentioned method of carrying out dynamic cross-linking simultaneously with melt-kneading.

The composition of the present invention comprises (A) as described above.
By crosslinking the components by a silanol condensation reaction, particularly excellent characteristics are exhibited. Water supply is effective for the silanol condensation reaction, and the water supply method in the present invention is not particularly limited. For example, (1) a method for supplying water during kneading of the composition, (2) kneading The method of supplying water to the composition just before molding, (3) the method of supplying water after molding the kneaded composition, and the like,
It is possible to control the silanol condensation reaction. Especially (1),
(2) is preferable.

In the case of a method of adding water etc. before kneading
In this case, various addition methods can be selected, for example, water and / or
Or hydrolyzable group-containing silane compound is mixed before kneading
Machine or static or mechanical mixer
More mixing method, containing hydrolyzable groups with high temperature dependence
Add a silane compound and control the reaction by changing the temperature
Method, adding a compound that adsorbs water, and changing the temperature
Examples include methods for controlling the reaction. Supply of necessary water
Hydration of metal salts when using metal salt hydrates as sources
It is possible to use a wide variety of commercially available products.
Such as hydrates of alkaline earth metal salts, other metals
Examples thereof include hydrates of salts. Among these, alkali
Metal salt hydrates and alkaline earth metal salt hydrates are preferred.
Specifically, MgSO _Four・ 7H₂O, Na₂CO₃・ 1
0H₂O, Na₂SO_Four・ 10H₂O, Na₂S₂O₃・ 5H₂
O, Na₃PO_Four・ 12H₂O, Na₂B_FourO₇・ 10H₂O
Etc. The hydrate of the metal salt is an isoform of the component (A).
0.01 to 50 parts per 100 parts of butylene-based copolymer
It is preferable to use in the range of. In particular, 0.1-30
Parts, further 1 to 20 parts, further 2 to 10 parts.
It is preferable to use it in the enclosure. One hydrate of the above metal salts
It may be used alone or in a mixture of two or more
good.

The thermoplastic elastomer composition of the present invention comprises
The thermoplastic resin composition can be molded by using a molding method and a molding apparatus generally adopted, and for example, melt molding can be performed by extrusion molding, injection molding, press molding, blow molding or the like.

The crosslinkable composition of the present invention is used for foods, daily sundries, toys, sports and sports equipment, stationery,
Automotive interior / exterior applications, civil engineering / construction applications, AV / home appliance applications, OA / office equipment applications, electrical / electronic equipment, etc.
Footwear, textiles, medical, hygiene,
It can be used for packaging and transportation, electric wires, etc.

Specifically, the thermoplastic elastomer composition of the present invention is excellent in flexibility, moldability and compression set characteristics, and is molded into a sheet, a molded body, a pressure sensitive adhesive body, a foamed body, etc.・ Sheets such as waterproof sheets, packing materials, seal materials, sealing materials such as gaskets and stoppers, vibration dampers and vibration dampers for automobiles, vehicles and home appliances such as building dampers and CD dampers, medical catheters, medical containers , Medical caps, disposable diapers, sanitary items, wire coating materials, cables, connectors, plugs, automotive interior materials, automotive molding materials, other containers, cushion materials, grip materials, cushioning materials, packaging materials, asphalt reforming It can be effectively used as an agent and a resin modifier.

[0063]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited thereto. In addition, prior to the examples, various measuring methods, evaluation methods,
Examples will be described.

(Hardness) According to JIS K 6352, a 12.0 mm pressure press sheet was used as a test piece.

(Compression set) According to JIS K 6262, a 12.0 mm thick press sheet was used as a test piece. It was measured under conditions of 100 ° C. × 22 hours and 25% deformation. Further, the abbreviations of the materials used in Examples and Comparative Examples below and their specific contents are as follows. Component (A): SiSIBS: polystyrene-polyisobutylene-polystyrene triblock copolymer containing a methyldimethoxy group at both ends of the molecule [number average molecular weight 150
00, molecular weight dispersity 1.5] Component (B): PP: polypropylene, manufactured by Mitsui Chemicals, Inc. (trade name "HIPOL J300") Component (C): Silanol condensation catalyst: Dibutyltin dilaurate Component (E): Plasticizer: Paraffin Type process oil, manufactured by Idemitsu Petrochemical Co., Ltd. (trade name "Diana Process Oil PW
-90 ") SIBS: polystyrene-polyisobutylene-polystyrene triblock copolymer [number average molecular weight 67,000,
Molecular Weight Dispersity 1.5] (Production Example 1) [Production of polystyrene-polyisobutylene-polystyrene triblock copolymer (SiSIBS) in which a silicon group bonded to a methoxy group is introduced at the end] Polymerization of 2 L separable flask After purging the inside of the container with nitrogen, using a syringe, n-hexane (dried with molecular sieves) 456.1 mL and butyl chloride (dried with molecular sieves) 656.5 m
After L was added and the polymerization container was put in a dry ice / methanol bath at -70 ° C. and cooled, a pressure-resistant glass liquefaction collection tube with a three-way cock containing 201 mL (2132 mmol) of isobutylene monomer was made of Teflon (registered trademark). A liquid-feeding tube was connected, and the isobutylene monomer was fed into the polymerization container by nitrogen pressure. 2.6 g (11.2 mmol) of p-dicumyl chloride and 1.22 g (14 mmol) of N, N-dimethylacetamide were added.
Next, titanium tetrachloride 9.9mL (90.0mmo
1) was added to initiate polymerization. After stirring at the same temperature for 1.5 hours from the start of the polymerization, about 1 mL of the polymerization solution was sampled from the polymerization solution for sampling. Then, the styrene monomer 52 previously cooled to -70 ° C.
A mixed solution of g (499 mmol), n-hexane 23.9 mL and butyl chloride 34.3 mL was added into the polymerization vessel.

45 minutes after the addition of the mixed solution, 12 ml (10.0 mmol) of allyltrimethylsilane was added. After stirring for 60 minutes at the same temperature, about 40m
The reaction was terminated by adding L of methanol.

After distilling off the solvent and the like from the reaction solution, it was dissolved in toluene and washed twice with water. Further, a toluene solution was added to a large amount of methanol to precipitate a polymer, and the obtained polymer was vacuum dried at 60 ° C. for 24 hours to obtain a target block copolymer. The molecular weight of the polymer obtained by the gel permeation chromatography (GPC) method was measured. Mn of the isobutylene polymer before addition of styrene was 10500, Mw / Mn was 1.40, and Mn of the block copolymer after styrene polymerization was 15000, M
A block copolymer having a w / Mn of 1.50 was obtained.

80 g of the thus obtained allyl-terminated polystyrene-polyisobutylene-polystyrene triblock copolymer was reacted with 2.8 g of dimethoxymethylsilane. As catalyst, platinum vinyl siloxane complex (0.00000831 mmol / μL xylene solution)
5.6 mg was added. The reaction was carried out at 90 ° C. for 8 hours. After drying under reduced pressure, a polystyrene-polyisobutylene-polystyrene triblock copolymer having a silicon group bonded to a methoxy group at the terminal was obtained.

(Production Example 2) [Styrene-isobutylene-
Production of Styrene Block Copolymer (SIBS)] After replacing the inside of the polymerization vessel of a 2 L separable flask with nitrogen, using a syringe, 456.1 mL of n-hexane (dried with molecular sieves) and butyl chloride (molecular) (Dried with sieves) 656.5 m
L was added, the polymerization container was placed in a dry ice / methanol bath at -70 ° C. and cooled, and then a pressure-resistant glass liquefaction sampling tube with a three-way cock containing 232 mL (2871 mmol) of isobutylene monomer was made of Teflon (registered trademark). A liquid-feeding tube was connected, and the isobutylene monomer was fed into the polymerization container by nitrogen pressure. 0.647 g (2.8 mmol) of p-dicumyl chloride and 1.22 g (14 mmol) of N, N-dimethylacetamide were added. Next, a further 8.67 mL of titanium tetrachloride (79.1 m
(mol) was added to initiate polymerization. 1.5 from the start of polymerization
After stirring at the same temperature for an hour, about 1 mL of the polymerization solution was withdrawn from the polymerization solution for sampling. continue,
77.9 g (748 mmol) of styrene monomer which had been cooled to -70 ° C in advance, and n-hexane of 23.9.
A mixed solution of mL and butyl chloride (34.3 mL) was added into the polymerization vessel. 45 minutes after adding the mixed solution, about 40 mL of methanol was added to terminate the reaction.

After distilling off the solvent and the like from the reaction solution, it was dissolved in toluene and washed twice with water. Further, a toluene solution was added to a large amount of methanol to precipitate a polymer, and the obtained polymer was vacuum dried at 60 ° C. for 24 hours to obtain a target block copolymer. The molecular weight of the polymer obtained by the gel permeation chromatography (GPC) method was measured. Mn of the isobutylene polymer before styrene addition was 50,000, Mw / Mn was 1.40, and Mn of the block copolymer after styrene polymerization was 67,000.
A block copolymer having 0 and Mw / Mn of 1.50 was obtained. (Example 1) 100 parts SiSiBS, 25 parts PP,
These were melt-kneaded using a Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.) set at 170 ° C., then 150 parts of a plasticizer,
After adding 2.5 parts of silanol condensation catalyst and melt-kneading,
While gradually adding water, the mixture was further melt-kneaded at 170 ° C. until the torque value reached the maximum value, and dynamic crosslinking was performed. The obtained thermoplastic elastomer composition could be easily formed into a sheet by a pressure press manufactured by Shindo Metal Industry Co., Ltd. at 180 ° C. The hardness and compression set of the obtained sheet were measured according to the methods described above. The hardness was 42 and the compression set was 40%. (Comparative Example 1) SIBS was melt-kneaded for 10 minutes using a Labo Plastomill set to 180 ° C, and then molded into a sheet at 180 ° C. The obtained sheet had a hardness of 47 and a compression set of 87%.

[0071]

[Table 1] As described above, the thermoplastic elastomer composition of Example 1 has almost the same hardness as SIBS alone which is the isobutylene block copolymer shown in Comparative Example 1,
The compression set value was considerably lower than that of BS alone.

[0072]

INDUSTRIAL APPLICABILITY As described above, the thermoplastic elastomer composition of the present invention is a novel thermoplastic elastomer composition having excellent flexibility and excellent moldability, particularly compression set characteristics.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4F070 AA12 AA18 AB07 AB08 AB09                       AB11 AB16 GA01 GA05 GB08                 4J002 AE05Y BB00X BP03W CP17W                 4J026 HA02 HA39 HB05 HB39 HB50                       HE02

Claims (8)

[Claims] 1. An isobutylene polymer block (a) having a hydrolyzable group or a silicon group bonded to a hydroxyl group at the terminal.
A thermoplastic elastomer composition containing an isobutylene block copolymer (A) containing a polymer block (b) mainly containing an aromatic vinyl compound and an olefin resin (B) 2. An isobutylene block copolymer (A) 1
The thermoplastic elastomer composition according to claim 1, which contains 10 to 200 parts by weight of the olefin resin (B) with respect to 00 parts by weight. 3. A thermoplastic elastomer composition comprising an isobutylene block copolymer (A) and an olefin resin (B).
3. The composition according to claim 1, which is dynamically cross-linked during melt kneading.
The thermoplastic elastomer composition according to. 4. The thermoplastic elastomer composition according to claim 1, further comprising a silanol condensation catalyst as the component (C). 5. The thermoplastic elastomer composition according to claim 1, further comprising a plasticizer as the component (D). 6. The total amount of plasticizer (D) (A) and (B) is 1
6. 10 to 300 parts by weight based on 00 parts by weight
The thermoplastic elastomer composition described. 7. The isobutylene block copolymer (A) has a number average molecular weight of 2000 to 100,000 and has at least one hydrolyzable group or a silicon group bonded to a hydroxyl group at the end per molecule. The thermoplastic elastomer composition according to any one of claims 1 to 5, which is a copolymer. 8. An isobutylene-based block copolymer (A) having a hydrolyzable group or a silicon group bonded to a hydroxyl group at the terminal comprises an isobutylene-based polymer block (a) and an aromatic vinyl compound. The thermoplastic elastomer composition according to any one of claims 1 to 3, wherein the main polymer block (b) is a triblock copolymer having a structure of (b)-(a)-(b).