JP5331346B2 - Method for producing thermoplastic elastomer composition - Google Patents

Description

  The present invention relates to a method for producing a novel thermoplastic elastomer composition which is rich in flexibility, excellent in molding processability and compression set characteristics, and particularly excellent in surface properties of a molded article.

  Conventionally, as a polymer material having elasticity, a material obtained by blending a rubber such as natural rubber or synthetic rubber with a crosslinking agent or a reinforcing agent and crosslinking under high temperature and high pressure has been widely used. However, such rubbers require a process of crosslinking and molding for a long time under high temperature and pressure, and are inferior in processability. In addition, since the crosslinked rubber does not exhibit thermoplasticity, it cannot be recycled as with a thermoplastic resin. Therefore, in recent years, it has been possible to easily produce molded products using general-purpose melt molding techniques such as hot press molding, injection molding, and extrusion molding as well as general thermoplastic resins, and recycling molding. Various possible thermoplastic elastomers have been developed. As such thermoplastic elastomers, there are various types of polymers such as olefins, urethanes, esters, styrenes, vinyl chlorides, etc., which are also commercially available.

  Of these, olefin-based thermoplastic elastomers are excellent in heat resistance, cold resistance, weather resistance, and the like. Olefin-based thermoplastic elastomers include a crosslinked type and a non-crosslinked type. Non-crosslinked thermoplastic elastomers do not involve a crosslinking reaction, so there is little variation in quality and production costs are low, but tensile strength, elongation at break, rubber properties (permanent elongation, compression set, etc.), heat resistance And low temperature characteristics are not necessarily sufficient. On the other hand, the cross-linked thermoplastic elastomer is excellent in terms of tensile strength, elongation at break, rubber-like properties (for example, permanent elongation, compression set) and heat resistance (see Non-Patent Document 1, Patent Documents 1-13, etc.). . However, cross-linked thermoplastic elastomers using conventional cross-linking agents such as sulfur, peroxides, and phenolic resins increase the degree of cross-linking and improve compression set, while cross-linking agents on the composition surface and by-products of the cross-linking reaction Bleeding of things occurs. For this reason, the development to applications requiring hygiene such as food and medical packaging materials has been limited.

  Further, the cross-linked thermoplastic elastomer has a phase structure in which cross-linked rubber is dispersed in a thermoplastic resin. However, if the particle diameter of the cross-linked rubber is large, the uniformity of the surface of the molded product is significantly impaired. It was.

Thus, it is difficult to obtain a thermoplastic composition having an excellent balance of physical properties, and as with conventional thermoplastic resins, it can be easily molded by hot pressing, injection molding, etc. Development of a thermoplastic elastomer composition excellent in physical property balance and molded article surface property is desired.
Japanese Patent Publication No.53-21021 Japanese Patent Publication No.55-18448 Japanese Patent Publication No.56-15741 Japanese Patent Publication No. 56-15742 Japanese Examined Patent Publication No. 58-46138 Japanese Patent Publication No.58-56575 Japanese Patent Publication No.59-30376 Japanese Patent Publication No.62-938 Japanese Examined Patent Publication No. 62-59139 JP-A-6-63850 JP-A-10-195241 JP 2000-351877 A JP 2006-265319 A Rubber Chemistry and Technology, A.R. Y. Coran et al., 53 (1980), 141 pages

An object of the present invention is to provide a thermoplastic elastomer composition which is rich in flexibility, excellent in compression set properties, gas barrier properties and vibration damping properties, and hygiene, and particularly excellent in surface properties of molded articles, in view of the above-described problems of the prior art. It is to provide a manufacturing method.

  As a result of intensive studies, the present inventors have completed the present invention. That is, the present invention relates to an isobutylene polymer (A) having an alkenyl group at the terminal, a polypropylene resin (B1) and / or a polyethylene resin (B2) and / or a styrene-isobutylene-styrene block copolymer (B3). This is a process for producing a thermoplastic elastomer composition obtained by dynamically crosslinking an isobutylene polymer (A) with a hydrosilyl group-containing polysiloxane (C) while melt kneading the resin component (B), Addition of the polymer (A) into the melt-kneading system is added at least twice, and the addition amount of each time is in the range of 20 to 80% of the final charged amount of the isobutylene polymer (A). The manufacturing method of the thermoplastic elastomer composition characterized by these.

  As a preferable embodiment, from 100 parts by weight of the isobutylene polymer (A), from the polypropylene resin (B1) and / or the polyethylene resin (B2) and / or the styrene-isobutylene-styrene block copolymer (B3). It is related with the manufacturing method of the thermoplastic elastomer composition which contains 5-100 weight part of resin components (B) which become.

As a preferred embodiment, the present invention further relates to a method for producing a thermoplastic elastomer composition containing 1 to 300 parts by weight of a softener (D) with respect to 100 parts by weight of an isobutylene polymer (A).
A preferred embodiment relates to a method for producing a thermoplastic elastomer composition in which the softening agent (D) is paraffinic oil or polybutene.
As a preferred embodiment, the present invention relates to a method for producing a thermoplastic elastomer composition in which the polypropylene resin (B1) is random polypropylene.
As a preferred embodiment, the present invention relates to a method for producing a thermoplastic elastomer composition in which the polyethylene resin (B2) is high-density polyethylene.

  The composition according to the present invention can be easily molded by a general technique such as hot pressing and injection molding, as in the case of conventional thermoplastic resins. In addition, the composition according to the present invention is not only rich in flexibility and rubber elasticity, but also exhibits good gas barrier properties, hygiene, compression set properties, vibration damping properties and particularly good surface properties. For this reason, it can be used suitably for various uses such as sealing materials for sealing such as medical medicine stoppers and cap liners for beverages, ink tubes for printers, hoses and cushioning materials.

The composition of the thermoplastic elastomer composition of the present invention comprises an isobutylene polymer (A) having an alkenyl group at the terminal, a polypropylene resin (B1) and / or a polyethylene resin (B2) and / or styrene-isobutylene-styrene. The isobutylene polymer (A) is dynamically cross-linked with the hydrosilyl group-containing polysiloxane (C) while melt-kneading the resin component (B) comprising the block copolymer (B3), and the isobutylene polymer (A). Is added in portions at least twice, and the addition amount of each time is in the range of 20 to 80% of the final charged amount of the isobutylene polymer (A).
The isobutylene polymer (A) of the present invention is a polymer having isobutylene as a main component and having an alkenyl group at the terminal. From the viewpoint of gas barrier properties, the isobutylene polymer (A) preferably contains 50% by weight or more of isobutylene, more preferably 70% by weight or more, and still more preferably 90% by weight or more. The monomer other than isobutylene of the isobutylene polymer (A) is not particularly limited as long as it is a monomer component that can be cationically polymerized, but aromatic vinyls, aliphatic olefins, isoprene, butadiene, divinylbenzene, and the like. Examples thereof include monomers such as dienes, vinyl ethers, and β-pinene. These may be used alone or in combination of two or more.

The number average molecular weight of the isobutylene polymer (A) is not particularly limited, but is preferably 1,000 to 500,000, particularly preferably 5,000 to 200,000. When the number average molecular weight is less than 1,000, mechanical properties and the like are not sufficiently exhibited, and when it exceeds 500,000, the moldability and the like are greatly deteriorated.
The alkenyl group of the isobutylene polymer (A) is not particularly limited as long as it is a group containing a carbon-carbon double bond that is active for the crosslinking reaction of the component (A). Specific examples include aliphatic unsaturated hydrocarbon groups such as vinyl group, allyl group, methyl vinyl group, propenyl group, butenyl group, pentenyl group, hexenyl group, cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclohexenyl group. And cyclic unsaturated hydrocarbon groups such as

As a method for introducing an alkenyl group into the terminal of the isobutylene polymer of the present invention (a method for producing the polymer (A)), it is disclosed in JP-A-3-152164 and JP-A-7-304909. Examples thereof include a method of introducing a unsaturated group into a polymer by reacting a polymer having a functional group such as a hydroxyl group with a compound having an unsaturated group. In order to introduce an unsaturated group into a polymer having a halogen atom, a method of performing a Friedel-Crafts reaction with an alkenylphenyl ether, a method of performing a substitution reaction with allyltrimethylsilane in the presence of a Lewis acid, and the like. Examples include a method in which a Friedel-Crafts reaction with phenols is performed to introduce a hydroxyl group, and then the alkenyl group introduction reaction is further performed. Further, as disclosed in U.S. Pat. No. 4,316,973, JP-A 63-105005, and JP-A 4-288309, it is also possible to introduce an unsaturated group during polymerization of the monomer. Among these, those in which an allyl group is introduced at the terminal by a substitution reaction of allyltrimethylsilane and chlorine are preferable from the viewpoint of certainty.
The amount of the alkenyl group at the end of the isobutylene polymer (A) can be arbitrarily selected depending on the required properties. From the viewpoint of the properties after crosslinking, at least 0.2 alkenyl groups per molecule are terminated. It is preferable that the polymer has If the number is less than 0.2, the effect of improving by crosslinking may not be sufficiently obtained.

  The polypropylene resin (B1) means a homopolymer or copolymer having propylene as a main component. Examples of the monomer to be copolymerized include monomers selected from ethylene and α-olefins having 3 to 20 carbon atoms. From the viewpoint of compatibility with the component (A), a random type polypropylene is preferable. The melt flow rate of the polypropylene resin (B1) is not particularly limited, but the melt flow rate at a load of 2.16 kg at 230 ° C. is preferably 50 g / 10 min or less, and more preferably 3 g to 20 g / 10 min. preferable. When the melt flow rate of the polypropylene resin (B1) is larger than 50 g / 10 minutes, heat resistance and mechanical strength tend to be inferior.

  The polyethylene resin (B2) is a homopolymer or copolymer having ethylene as a main component. The monomer to be copolymerized is a monomer selected from ethylene and an α-olefin having 3 to 20 carbon atoms. High-density polyethylene is preferred from the viewpoint of heat resistance. The melt flow rate of the polyethylene resin (B2) is not particularly limited, but the melt flow rate at 230 ° C. and 2.16 kg load is preferably 50 g / 10 min or less, and more preferably 3 g to 20 g / 10 min. preferable. When the melt flow rate of the polyethylene resin (B2) is larger than 50 g / 10 minutes, heat resistance and mechanical strength tend to be inferior.

The styrene-isobutylene-styrene block copolymer (B3) comprises a polymer block mainly composed of styrene and an isobutylene polymer block.
The polymer block mainly composed of styrene preferably has a unit derived from styrene of 60% by weight or more, more preferably 80% by weight or more from the balance of processing temperature, hardness and physical strength. It is a block.

  Preferred compounds other than styrene include o-, m- or p-methylstyrene, α-methylstyrene, β-methylstyrene, 2,6-dimethylstyrene, 2,4-dimethylstyrene, α-methyl-o-methyl. Styrene, α-methyl-m-methylstyrene, α-methyl-p-methylstyrene, β-methyl-o-methylstyrene, β-methyl-m-methylstyrene, β-methyl-p-methylstyrene, 2,4 , 6-trimethylstyrene, α-methyl-2,6-dimethylstyrene, α-methyl-2,4-dimethylstyrene, β-methyl-2,6-dimethylstyrene, β-methyl-2,4-dimethylstyrene, o-, m- or p-chlorostyrene, 2,6-dichlorostyrene, 2,4-dichlorostyrene, α-chloro-o-chlorostyrene, α-chloro-m-alkyl Rollostyrene, α-chloro-p-chlorostyrene, β-chloro-o-chlorostyrene, β-chloro-m-chlorostyrene, β-chloro-p-chlorostyrene, 2,4,6-trichlorostyrene, α-chloro -2,6-dichlorostyrene, α-chloro-2,4-dichlorostyrene, β-chloro-2,6-dichlorostyrene, β-chloro-2,4-dichlorostyrene, o-, m- or pt -Butyl styrene, o-, m- or p-methoxy styrene, o-, m- or p-chloromethyl styrene, o-, m- or p-bromomethyl styrene, styrene derivatives substituted with silyl groups, indene, Examples include vinyl naphthalene. Among these, from the viewpoint of industrial availability and glass transition temperature, α-methylstyrene, β-pinene, and mixtures thereof are preferable.

  The polymer block mainly composed of isobutylene is preferably composed of 60% by weight or more, more preferably 80% by weight or more of units derived from isobutylene from the viewpoint of the balance between gas barrier properties, hardness and physical strength. It is a polymer block.

  Any of the polymer blocks can use mutual monomers as copolymerization components, and other monomer components capable of cationic polymerization. Examples of such a monomer component include monomers such as aliphatic olefins, dienes, vinyl ethers, silanes, vinyl carbazole, β-pinene, and acenaphthylene. These can be used alone or in combination of two or more.

  Aliphatic olefin monomers include ethylene, propylene, 1-butene, 2-methyl-1-butene, 3-methyl-1-butene, pentene, hexene, cyclohexene, 4-methyl-1-pentene, vinylcyclohexane Octene, norbornene and the like.

  Examples of the diene monomer include butadiene, isoprene, hexadiene, cyclopentadiene, cyclohexadiene, dicyclopentadiene, divinylbenzene, and ethylidene norbornene.

  Examples of the vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, (n-, iso) propyl vinyl ether, (n-, sec-, tert-, iso) butyl vinyl ether, methyl propenyl ether, ethyl propenyl ether and the like.

  Examples of the silane compound include vinyltrichlorosilane, vinylmethyldichlorosilane, vinyldimethylchlorosilane, vinyldimethylmethoxysilane, vinyltrimethylsilane, divinyldichlorosilane, divinyldimethoxysilane, divinyldimethylsilane, 1,3-divinyl-1,1,3. , 3-tetramethyldisiloxane, trivinylmethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylmethyldimethoxysilane, and the like.

  The component (B3) of the present invention is not particularly limited in its structure as long as it is composed of a block mainly composed of styrene and a block mainly composed of isobutylene. For example, linear, branched, star-shaped, etc. Any of a block copolymer, a diblock copolymer, a triblock copolymer, a multiblock copolymer, and the like having the following structure can be selected. A preferable structure includes a triblock copolymer composed of styrene-isobutylene-styrene from the viewpoint of physical property balance and molding processability. These may be used alone or in combination of two or more in order to obtain desired physical properties and moldability.

  The ratio of the block mainly composed of styrene and the block mainly composed of isobutylene is not particularly limited, but from the viewpoint of flexibility and rubber elasticity, the content of the block mainly composed of styrene in the component (C) is 5 to 5. It is preferably 50% by weight, and more preferably 10 to 40% by weight.

  The molecular weight of the component (B3) is not particularly limited, but is preferably 30,000 to 500,000 in terms of weight average molecular weight by GPC measurement from the viewpoint of fluidity, molding processability, rubber elasticity, and the like. 000 to 300,000 is particularly preferable. When the weight average molecular weight is lower than 30,000, mechanical properties tend not to be sufficiently exhibited, whereas when it exceeds 500,000, fluidity and workability tend to deteriorate.

Although there is no restriction | limiting in particular about the manufacturing method of a component (B3), For example, it can obtain by polymerizing a monomer component in presence of the compound represented by following General formula (1).
(CR ¹ R ² X) _n R ³ (1)
[Wherein X is a halogen atom, a substituent selected from an alkoxy group having 1 to 6 carbon atoms or an acyloxy group, R ¹ and R ² are each a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, R ¹ , R ² may be the same or different, R ³ is a monovalent or polyvalent aromatic hydrocarbon group or a monovalent or polyvalent aliphatic hydrocarbon group, and n represents a natural number of 1 to 6. . ]
The compound represented by the general formula (1) serves as an initiator, and is considered to generate a carbon cation in the presence of a Lewis acid or the like and serve as a starting point for cationic polymerization. Examples of the compound of the general formula (1) used in the present invention include the following compounds.

(1-Chloro-1-methylethyl) benzene [C ₆ H ₅ C (CH ₃ ) ₂ Cl], 1,4-bis (1-chloro-1-methylethyl) benzene [1,4-Cl (CH ₃ ) ₂ CC ₆ H ₄ C (CH ₃ ) ₂ Cl], 1,3-bis (1-chloro-1-methylethyl) benzene [1,3-Cl (CH ₃ ) ₂ CC ₆ H ₄ C (CH ₃ ) ₂ Cl], 1,3,5-tris (1-chloro-1-methylethyl) benzene [1,3,5- (ClC (CH ₃ ) ₂ ) ₃ C ₆ H ₃ ], 1,3-bis (1-Chloro-1-methylethyl) -5- (tert-butyl) benzene [1,3- (C (CH ₃ ) ₂ Cl) ₂ -5- (C (CH ₃ ) ₃ ) C ₆ H ₃ ]
Among these, bis (1-chloro-1-methylethyl) benzene [C ₆ H ₄ (C (CH ₃ ) ₂ Cl) ₂ ], tris (1-chloro-1-methylethyl) benzene [( ClC (CH ₃ ) ₂ ) ₃ C ₆ H ₃ ]. [Bis (1-chloro-1-methylethyl) benzene is also called bis (α-chloroisopropyl) benzene, bis (2-chloro-2-propyl) benzene or dicumyl chloride, and tris (1-chloro- 1-methylethyl) benzene is also referred to as tris (α-chloroisopropyl) benzene, tris (2-chloro-2-propyl) benzene, or tricumyl chloride.

When the component (B3) is produced, a Lewis acid catalyst can be further present. Such Lewis acid may be any one that can be used for cationic polymerization. TiCl ₄ , TiBr ₄ , BCl ₃ , BF ₃ , BF ₃ .OEt ₂ , SnCl ₄ , SbCl ₅ , SbF ₅ , WCl ₆ , TaCl ₅ , VCl ₅ , FeCl ₃ , ZnBr ₂ , AlCl ₃ , AlBr _{3 and} other metal halides; Et ₂ AlCl, EtAlCl _{2 and} other organic metal halides can be suitably used. Of these, TiCl ₄ , BCl ₃ , and SnCl ₄ are preferable in view of the ability as a catalyst and industrial availability. The amount of Lewis acid used is not particularly limited, but can be set in view of the polymerization characteristics or polymerization concentration of the monomer used. Usually, it is 0.1-100 mol equivalent with respect to the compound represented by General formula (1), Preferably it is the range of 1-50 mol equivalent.

  In the production of the component (B3), an electron donor component can be allowed to coexist if necessary. This electron donor component is believed to have the effect of stabilizing the growth carbon cation during cationic polymerization, and the addition of an electron donor produces a polymer with a narrow molecular weight distribution and a controlled structure. be able to. The electron donor component that can be used is not particularly limited, and examples thereof include pyridines, amines, amides, sulfoxides, esters, and metal compounds having an oxygen atom bonded to a metal atom.

  The polymerization of the component (B3) can be carried out in an organic solvent as necessary, and the organic solvent can be used without particular limitation as long as it does not substantially inhibit cationic polymerization. Specifically, halogenated hydrocarbons such as methyl chloride, dichloromethane, chloroform, ethyl chloride, dichloroethane, n-propyl chloride, n-butyl chloride, chlorobenzene; benzene, toluene, xylene, ethylbenzene, propylbenzene, butylbenzene, etc. Alkylbenzenes; linear aliphatic hydrocarbons such as ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane; 2-methylpropane, 2-methylbutane, 2,3,3-trimethylpentane, 2 Branched aliphatic hydrocarbons such as 1,2,5-trimethylhexane; cycloaliphatic hydrocarbons such as cyclohexane, methylcyclohexane and ethylcyclohexane; paraffin oil obtained by hydrorefining petroleum fractions, etc. .

  These solvents can be used alone or in combination of two or more in consideration of the balance of the polymerization characteristics of the monomer constituting the component (B3) and the solubility of the polymer to be formed.

  The amount of the solvent used is determined so that the concentration of the polymer is 1 to 50 wt%, preferably 5 to 35 wt%, in consideration of the viscosity of the resulting polymer solution and the ease of heat removal.

In carrying out the actual polymerization, the respective components are mixed at a temperature of, for example, −100 ° C. or more and less than 0 ° C. under cooling. In order to balance the energy cost and the stability of polymerization, a particularly preferred temperature range is −30 ° C. to −80 ° C.
The amount of the resin component (B) added is preferably 5 to 300 parts by weight, more preferably 5 to 100 parts by weight, based on 100 parts by weight of the isobutylene block copolymer (A). When the amount of the resin component (B) added exceeds 300 parts by weight, the compression set characteristics tend to be significantly deteriorated, and when it is less than 5 parts by weight, the physical strength and moldability tend to be significantly reduced.
The hydrosilyl group-containing polysiloxane (C) is used for crosslinking the isobutylene polymer (A) having an alkenyl group introduced at the terminal. The hydrosilyl group-containing polysiloxane that can be used is not particularly limited, but is preferably a hydrosilyl group-containing polysiloxane having 3 or more hydrosilyl groups and 3 to 500 siloxane units, and having 3 or more hydrosilyl groups. Polysiloxane having 10 or more and 200 or less units is more preferable, and polysiloxane having 3 or more hydrosilyl groups and 20 or more and 100 or less siloxane units is particularly preferable. When the number of hydrosilyl groups is less than 3, sufficient growth of the network due to crosslinking tends not to be achieved and optimal rubber elasticity tends not to be obtained. When the number of siloxane units exceeds 500, the viscosity of the polysiloxane increases and the component (A ) The dispersibility into the inside tends to decrease, and the progress of the crosslinking reaction tends to be insufficient. The polysiloxane unit mentioned here refers to the following general formulas (I), (II), and (III).
[Si (R ¹ ) ₂ O] (I)
[Si (H) (R ² ) O] (II)
[Si (R ² ) (R ³ ) O] (III)
As the hydrosilyl group-containing polysiloxane, a linear polysiloxane represented by the general formula (IV) or (V);
_{^{R 1 3 SiO- [Si (R}} 1) 2 O] a - [Si (H) (R 2) O] b - [Si (R 2) (R 3) O] c -SiR 1 3 (IV)
_{^{HR 1 2 SiO- [Si (R}} 1) 2 O] a - [Si (H) (R 2) O] b - [Si (R 2) (R 3) O] c -SiR 1 2 H (V)
(In the formula, R ¹ and R ² represent an alkyl group having 1 to 6 carbon atoms or a phenyl group, and R ³ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group. B represents 3 ≦ b, a, b. , C represents an integer satisfying 3 ≦ a + b + c ≦ 500.)
A cyclic siloxane represented by the general formula (VI);

（式中、Ｒ^４およびＲ^５は炭素数１〜６のアルキル基、または、フェニル基、Ｒ^６は炭素数１〜１０のアルキル基またはアラルキル基を示す。ｅは３≦ｅ、ｄ，ｅ，ｆはｄ＋ｅ＋ｆ≦５００を満たす整数を表す。）等の化合物を用いることができる。

(In the formula, R ⁴ and R ⁵ represent an alkyl group having 1 to 6 carbon atoms or a phenyl group, and R ⁶ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group. E represents 3 ≦ e, d, e , F represents an integer satisfying d + e + f ≦ 500.) And the like can be used.

  The isobutylene polymer (A) having an alkenyl group at the terminal and the hydrosilyl group-containing polysiloxane (C) can be mixed at an arbitrary ratio. However, in terms of reactivity, the molar ratio of the alkenyl group to the hydrosilyl group (alkenyl Group / hydrosilyl group) is preferably in the range of 5 to 0.2, more preferably 2.5 to 0.4. When the molar ratio is 5 or more, the crosslinking is insufficient and sticky, and the compression set tends to deteriorate. When the molar ratio is less than 0.2, a large amount of active hydrosilyl groups remain after crosslinking. Hydrogen gas is generated by hydrolysis and tends to cause cracks and voids.

  The cross-linking reaction between the isobutylene polymer (A) and the hydrosilyl group-containing polysiloxane (C) proceeds by mixing and heating the two components, but a hydrosilylation catalyst is added to advance the reaction more quickly. can do. Such hydrosilylation catalyst is not particularly limited, and examples thereof include radical initiators such as organic peroxides and azo compounds, and transition metal catalysts.

  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, of m-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, acyl peroxides such as lauroyl peroxide, peracid esters such as t-butyl perbenzoate, diisopropyl percarbonate, di-2-ethylhexyl percarbonate Peroxydicarbonate such as 1,1- Peroxyketals such as di (t-butylperoxy) cyclohexane, 1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, 2,2′-azobisisobutyronitrile, 2,2 '-Azobis-2-methylbutyronitrile, 1,1'-azobis-1-cyclohexanecarbonitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azoisobutyrovalero Examples include azo compounds such as nitriles.

Also, it is not particularly limited as a transition metal catalyst, for example, platinum simple substance, alumina, silica, carbon black or the like dispersed in a platinum solid, chloroplatinic acid, chloroplatinic acid and alcohol, aldehyde, ketone, etc. And a platinum-olefin complex and a platinum (0) -dialkenyltetramethyldisiloxane complex. Examples of the catalyst other than platinum _{compounds, RhCl (PPh 3) 3,} RhCl 3, RuCl 3, IrCl 3, FeCl 3, AlCl 3, PdCl 2 · H 2 O, NiCl 2, TiCl 4 , and the like. These catalysts may be used alone or in combination of two or more. Although there is no restriction | limiting in particular as a catalyst amount, It is good to use in the range of 10 ^{< -1} > ^-10 <^-8> mol with respect to 1 mol of alkenyl groups of a component (A), Preferably it is the range of 10 ^{< -3} > ^-10 <^-6> mol. It is good to use. When the amount is less than 10 ⁻⁸ mol, crosslinking tends not to proceed sufficiently. Moreover, since a clear effect is not seen even if it uses 10 ^<-1 > mol or more, it is preferable that it is less than 10 ^{< -1} > mol from the surface of economical efficiency. Of these, platinum vinyl siloxane is most preferred in terms of compatibility, crosslinking efficiency, and scorch stability.
In the present invention, as the component (D), a softener can be used as necessary for the purpose of imparting flexibility and molding fluidity. Although it does not specifically limit as a softening agent, Generally, a liquid or liquid material is used suitably at room temperature. Examples of such softeners include various rubber or resin softeners such as mineral oils, vegetable oils, and synthetics. Mineral oils include naphthenic and paraffinic process oils, and vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, palm oil, peanut oil, wax, pine Examples of synthetic systems include oil and olive oil, and liquid polybutene, low molecular weight polybutadiene, and the like. Among these, paraffin oil or polybutene is preferably used from the viewpoint of compatibility with the component (A) and gas barrier properties. Examples of the liquid polybutene include homopolymers such as 1-butene, 2-butene, and isobutene, and copolymers having these as the main components. Among these, homopolymers of isobutene or isobutene are mainly used. A copolymer with 1-butene or / and 2-butene as a component is preferred. The liquid polybutene preferably has a number average molecular weight of 500 to 6,000. When the number average molecular weight is less than 500, the thermoplastic elastomer composition is inferior in heat resistance and tends to be bleed and sticky on the surface of the molded product. It becomes difficult to disperse in

  These softeners may be used in an appropriate combination of two or more in order to obtain the desired hardness and melt viscosity.

  Component (D) is preferably blended in an amount of 1 to 500 parts by weight, more preferably 1 to 200 parts by weight, and more preferably 1 to 100 parts by weight per 100 parts by weight of component (A). Is more preferable. If it exceeds 500 parts by weight, the softening agent tends to bleed out from the surface of the molded article, which is not preferable.

  The timing for adding the component (D) is not particularly limited, and may be added at the time of dynamic crosslinking of the component (A) or after dynamic crosslinking.

  The addition of component (A) is preferably added in two or more portions to improve the dispersibility of component (A). The ratio of each division is preferably in the range of 10 to 80% with respect to the final charge amount of component (A). If it is less than 10% or exceeds 80%, the effect of divided addition may be lost. It is preferable that the component (C) and the catalyst are also added in accordance with the split ratio of the component (A) in order to make the cross-linking reaction uniform as the component (A) is added in portions. It is preferable that 70% or more of the component (A) added before the second and subsequent divided (A) components is insoluble in hexane. If it is less than 70%, the cross-linking reaction is insufficient, and there is a possibility that the effect of divided addition cannot be obtained. In addition, about the component added at once, it is not necessary to add all the quantities collectively at once, and if necessary, the component added at once may be charged over time continuously. Further, even if it is added formally in two or more times, for example, if the time interval is extremely short, and it seems that it is added substantially once from the viewpoint of those skilled in the art, it is once in the present invention. Is considered to be added.

  For melt kneading, a known method may be employed, and the above-described batch kneader or continuous kneader can be used. Examples thereof include a melt kneading method using an extruder, a Banbury mixer, a roll, and the like. Although the kneading | mixing temperature at this time does not have limitation in particular, the range of 100-250 degreeC is preferable, and the range of 150-220 degreeC is more preferable. When the kneading temperature is lower than 100 ° C., melting tends to be insufficient, and when it is higher than 250 ° C., deterioration due to heating may start to occur.

  In addition, the composition of the present invention can be further subjected to, for example, ethylene-propylene copolymer rubber (EPM) or ethylene-propylene-diene terpolymer in a range that does not impair the physical properties according to the required properties according to each application. Flexible olefin-based polymers such as rubber (EPDM), ethylene-butene copolymer rubber (EBM), amorphous poly α-olefin (APAO), ethylene-octene copolymer, in addition to hindered phenols and phosphorus, Sulfur antioxidants, hindered amine UV absorbers, light stabilizers, pigments, surfactants, flame retardants, antiblocking agents, antistatic agents, lubricants, silicone oils, fillers, reinforcing agents, etc. can do. As inorganic fillers, light calcium carbonate, heavy or calcium carbonate, other calcium fillers, hard clay, soft clay, kaolin clay, talc, wet silica, dry silica, amorphous silica, wollastonite, synthetic or natural zeolite Diatomaceous earth, silica sand, pumice powder, slate powder, alumina, aluminum sulfate, barium sulfate, calcium sulfate, molybdenum disulfide, magnesium hydroxide, aluminum hydroxide, and those obtained by silane treatment. These additives can be used in combination of two or more. For example, it is possible to improve hardness and tensile strength by including an inorganic filler. In addition, when a metal hydroxide such as magnesium hydroxide or aluminum hydroxide is used as the inorganic filler, it may be possible to impart excellent flame retardancy. Further, as the anti-blocking agent, for example, silica, zeolite and the like are suitable, and these may be either natural or synthetic, and true spherical crosslinked particles such as crosslinked acrylic true spherical particles are also suitable. As the antistatic agent, N, N-bis- (2-hydroxyethyl) -alkylamines and glycerin fatty acid esters having an alkyl group having 12 to 18 carbon atoms are preferable. Further, the lubricant is preferably a fatty acid amide, and specific examples include erucic acid amide, behenic acid amide, stearic acid amide, oleic acid amide and the like.

  The thermoplastic elastomer composition of the present invention can be molded using a molding method and molding apparatus generally employed for a thermoplastic resin composition, for example, melt molding by extrusion molding, injection molding, press molding, blow molding or the like. it can. Further, the thermoplastic elastomer composition of the present invention is excellent in moldability, hygiene, vibration damping, gas barrier properties, compression set properties, sealing materials such as packing materials, sealing materials, gaskets, plugs, Specifically, medical medicine plugs and beverage cap liners, CD dampers, architectural dampers, vibration control materials such as vibration control materials for automobiles, vehicles and home appliances, vibration damping materials, automotive interior materials, cushion materials, daily necessities It can be used effectively as electrical parts, electronic parts, sports members, grips or cushioning materials, wire covering materials, packaging materials, various containers, and stationery parts.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited by these.
Prior to the examples, various measurement methods, evaluation methods, and examples will be described.
(hardness)
In accordance with JIS K6253, the hardness (hereinafter abbreviated as JIS-A hardness) was measured with a spring type A durometer. For the hardness, a value immediately after measurement was adopted. The test piece used was a 12.0 mm thick press sheet.
(Tensile strength)
In accordance with JIS K 6251, a 2 mm-thick press sheet punched into No. 3 with a dumbbell was prepared as a test piece, and this was used for measurement. The tensile speed was 500 mm / min.
(Tensile elongation)
In accordance with JIS K 6251, a 2 mm-thick press sheet punched into a No. 3 type with a dumbbell was prepared as a test piece, and this was used for measurement. The tensile speed was 500 mm / min.
(Compression set)
In accordance with JIS K 6262, a press-molded body having a diameter of 30 mm and a thickness of 12.5 mm was used as a test piece. The measurement was performed at 100 ° C. for 22 hours under the conditions of 25% deformation.
(Molded surface properties)
The surface irregularities of a 2 mm thick 120 mm square sheet obtained by molding the obtained thermoplastic elastomer composition with an injection molding machine were evaluated. When the irregularities could be confirmed by visual observation, it was rated as x.
(Dispersibility)
5 minutes using 20 g of the obtained thermoplastic elastomer composition and carbon black (manufactured by Mitsubishi Chemical Corporation, 0.1 g of trade name “Mitsubishi Carbon Black # 45L”) set at 170 ° C. (manufactured by Toyo Seiki Co., Ltd.) After melt-kneading and then pressing at 180 ° C. to obtain a film having a thickness of 200 μm, the film was observed with a light panel CL-5000P manufactured by CABIN Co., Ltd., and the dispersibility was observed. If not, it was marked as ○.
Component (A): APIB: Polyisobutylene having an allyl group introduced at the terminal (Production Example 1)
Component (B1): RPP: Polypropylene, manufactured by Prime Polymer Co., Ltd. (trade name “Prime Polypro J215W”)
Component (B2): HDPE: High-density polyethylene, manufactured by Prime Polymer Co., Ltd. (trade name “Hi-Zex 2200J”)
Component (B3): SIBS: Styrene-isobutylene-styrene block copolymer (Production Example 2)
Component (C): Methyl hydrogen polysiloxane, manufactured by Toshiba Silicone Co., Ltd. (trade name “TSF484”)
Cross-linking catalyst:
1, valent 3,3-tetramethyl-1,3-dialkenyldisiloxane complex of zero-valent platinum, 3% by weight xylene solution component (D): polybutene: manufactured by Idemitsu Kosan Co., Ltd. (trade name “Idemitsu polybutene 100R”)
(Production Example 1) [Production of Isobutylene Copolymer (APIB) Introduced with Alkenyl Group at Terminal]
A 3 L faucet, a thermocouple, and a stirring seal were attached to a 2 L separable flask, and nitrogen substitution was performed. After nitrogen substitution, nitrogen was flowed using a three-way cock. To this, 785 ml of toluene and 265 ml of ethylcyclohexane were added using a syringe. After adding the solvent, the water content was measured with a Karl Fischer moisture meter. After the measurement, it was cooled to about -70 ° C. 277 ml (2933 mmol) of isobutylene monomer was added. After cooling to about −70 ° C. again, 0.85 g (3.7 mmol) of p-dicumyl chloride and 0.68 g (7.4 mmol) of picoline were dissolved in 10 ml of toluene and added. When the internal temperature of the reaction system became -74 ° C and stabilized, 19.3 ml (175.6 mmol) of titanium tetrachloride was added to initiate polymerization. When the polymerization reaction was completed (90 minutes from the start of the reaction), 1.68 g (11.0 mmol) of a 75% allylsilane / toluene solution was added, and the mixture was further reacted for 2 hours. Then, it deactivated with the pure water heated at about 50 degreeC, Furthermore, the organic layer was wash | cleaned 3 times with pure water (70 to 80 degreeC), and the organic solvent was removed at 80 degreeC under reduced pressure, and APIB was obtained. . A polymer having Mn of 45500, Mw / Mn of 1.10, and an allyl group content of 2.0 / mol was obtained.
(Production Example 2) [Production of styrene-isobutylene-styrene block copolymer (SIBS)]
After replacing the inside of the polymerization vessel of the 2 L separable flask with nitrogen, 456.1 mL of n-hexane (dried with molecular sieves) and 656.5 mL of butyl chloride (dried with molecular sieves) were added using a syringe. After cooling the polymerization vessel in a dry ice / methanol bath at −70 ° C., a polytetrafluoroethylene liquid feeding tube was placed on a pressure-resistant glass liquefied collection tube with a three-way cock containing 232 mL (2871 mmol) of isobutylene monomer. Then, isobutylene monomer was fed into the polymerization vessel 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, 8.67 mL (79.1 mmol) of titanium tetrachloride was further added to initiate polymerization. After stirring at the same temperature for 1.5 hours from the start of polymerization, about 1 mL of the polymerization solution was extracted from the polymerization solution for sampling. Subsequently, a mixed solution of 77.9 g (748 mmol) of styrene monomer, 23.9 mL of n-hexane and 34.3 mL of butyl chloride, which had been cooled to −70 ° C. in advance, was added to the polymerization vessel. 45 minutes after adding the mixed solution, about 40 mL of methanol was added to terminate the reaction.

  After the solvent was distilled off from the reaction solution, the precipitated solid was dissolved in toluene and washed twice with water. Further, the 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. The block copolymer in which the Mn of the isobutylene polymer before styrene addition is 50,000 and Mw / Mn is 1.40, the Mn of the block copolymer after styrene polymerization is 67,000 and Mw / Mn is 1.50. A polymer was obtained.

Example 1
The component (A), component (B1), component (C), component (D), and catalyst obtained in Production Example 1 were weighed to a total of 40 g in the proportions shown in Formulation system 1 in Table 1, According to the ratio shown in 2, the component (A), the component (C), and the catalyst were divided into 33% and 67%. Next, the component (A) divided into 33%, the component (B1) total amount kneaded for 3 minutes in a lab plast mill set at 170 ° C., and then divided into 33% of the component (C), catalyst 3 minutes after the one that was divided into 33% of the above was introduced and the maximum value of the torque was shown, the one that was divided into 67% of the component (A) was added, and after 3 minutes, it was divided into 67% of the component (C) The catalyst was divided into 67% and taken out 3 minutes after the maximum value of torque was shown. The obtained thermoplastic elastomer composition could be easily formed into a sheet shape at 190 ° C. with a heating press (manufactured by Shindo Metal Industry Co., Ltd.). The obtained sheet was measured for hardness, tensile properties, and dispersibility according to the above methods. Table 2 shows the physical properties of each sheet.

(Example 2)
A thermoplastic elastomer composition was obtained in the same manner as in Example 1 except that the number of divisions was changed to 3 and the division ratio was changed to 33%, 33%, and 34%, and physical properties were evaluated. The total amount of component (B1) was mixed with what was initially divided into 33% of (A). The respective physical properties are shown in Table 2.

(Example 3)
A thermoplastic elastomer composition was obtained in the same manner as in Example 1 except that the blending was changed to the blending system 2 in Table 1 and the split ratio was changed to 67% and 33%, and the physical properties were evaluated. The total amount of component (B2) was first mixed with 67% of (A). The respective physical properties are shown in Table 2.

Example 4
A thermoplastic elastomer composition was obtained in the same manner as in Example 3 except that the number of divisions was changed to 3 and the division ratio was changed to 16.5%, 16.5%, and 67%, and physical properties were evaluated. The total amount of component (B2) was mixed with what was initially divided into 16.5% of (A). The respective physical properties are shown in Table 2.

(Example 5)
A thermoplastic elastomer composition was obtained in the same manner as in Example 1 except that the blending was changed to the blending system 3 in Table 1 and the split ratio was changed to 25% and 75%, and the physical properties were evaluated. The total amount of component (B3) was mixed with what was initially divided into 25% of (A). The respective physical properties are shown in Table 2.

(Example 6)
A thermoplastic elastomer composition was obtained in the same manner as in Example 5 except that the number of divisions was changed to 3 and the division ratio was changed to 50%, 25%, and 25%, and physical properties were evaluated. The total amount of component (B3) was mixed with what was initially divided into 50% of (A). The respective physical properties are shown in Table 2.

(Comparative Example 1)
The component (A), component (B1), component (C), component (D), and catalyst obtained in Production Example 1 were weighed to a total of 40 g in the proportions shown in the blending system 1 in Table 1. Next, the total amount of the component (A) and the total amount of the component (B1) were kneaded in a lab plast mill set at 170 ° C. for 3 minutes, and then the total amount of the component (C) and the total amount of the catalyst were added and the maximum value of torque was shown for 3 minutes. It was taken out later. The obtained thermoplastic elastomer composition was able to be formed into a sheet shape at 190 ° C. with a heating press (manufactured by Shindo Metal Industry Co., Ltd.). The obtained sheet was measured for hardness, tensile properties, and dispersibility according to the above methods. Table 3 shows the physical properties of each sheet.

(Comparative Example 2)
A thermoplastic elastomer composition was obtained in the same manner as in Example 1 except that the split ratio was changed to 5% and 95%, and the physical properties were evaluated. The total amount of component (B1) was mixed with what was initially divided into 5% of (A). The respective physical properties are shown in Table 3.

(Comparative Example 3)
A thermoplastic elastomer composition was obtained in the same manner as in Comparative Example 1 except that the blending was changed to the blending system 2 in Table 1, and the physical properties were evaluated. The respective physical properties are shown in Table 3.

(Comparative Example 4)
A thermoplastic elastomer composition was obtained in the same manner as in Example 3 except that the split ratio was changed to 95% and 5%, and the physical properties were evaluated. The total amount of component (B2) was first mixed with 95% of (A). The respective physical properties are shown in Table 3.

(Comparative Example 5)
A thermoplastic elastomer composition was obtained in the same manner as in Comparative Example 1 except that the blending was changed to the blending system 3 in Table 1, and the physical properties were evaluated. The respective physical properties are shown in Table 3.

(Comparative Example 6)
A thermoplastic elastomer composition was obtained in the same manner as in Example 6 except that the division number was changed to 5%, 5%, and 90%, and the physical properties were evaluated. The total amount of component (B3) was mixed with what was initially divided into 5% of (A). The respective physical properties are shown in Table 3.

実施例１〜６はすべて成型体表面性、および分散性に優れている。それに対して分割を行っていない、比較例１、３、５と分割比率が１０％より小さい、もしくは９０％より大きい比較例２、４，６は成型体表面性、および分散性に劣る結果ということが分かる。
上記のことから、本発明の製造法にかかる組成物は、硬度、圧縮永久歪み特性、強度のバランスの取れた材料であり、特に成型体の表面性に優れることが分かる。従って、これらの特性が要求される、飲料用キャップライナーや医療用薬栓、プリンタ用インクチューブ、ホース、などに好適に用いることができる。

Examples 1 to 6 are all excellent in surface properties of the molded body and dispersibility. On the other hand, Comparative Examples 1, 3, 5 and Comparative Examples 2, 4, and 6 in which Comparative Examples 1, 3, and 5 and the dividing ratio are smaller than 10% or larger than 90% are results of inferior molding surface properties and dispersibility. I understand that.
From the above, it can be seen that the composition according to the production method of the present invention is a material having a good balance of hardness, compression set characteristics, and strength, and is particularly excellent in surface properties of a molded body. Therefore, it can be suitably used for cap liners for beverages, medical drug stoppers, ink tubes for printers, hoses, etc., which require these characteristics.

Claims (6)

Resin component (B) comprising an isobutylene polymer (A) having an alkenyl group at the terminal, a polypropylene resin (B1) and / or a polyethylene resin (B2) and / or a styrene-isobutylene-styrene block copolymer (B3) ) Is melt-kneaded and the isobutylene polymer (A) is dynamically crosslinked with the hydrosilyl group-containing polysiloxane (C) to produce a thermoplastic elastomer composition. The isobutylene polymer (A) Heat added to the melt-kneading system is added at least twice, and the amount of each addition is in the range of 10 to 80% of the final charge of the isobutylene polymer (A). A method for producing a plastic elastomer composition. Resin component (B) composed of polypropylene resin (B1) and / or polyethylene resin (B2) and / or styrene-isobutylene-styrene block copolymer (B3) with respect to 100 parts by weight of isobutylene polymer (A) 5 to 100 parts by weight of the thermoplastic elastomer composition according to claim 1. Furthermore, 1-300 weight part of softening agents (D) are contained with respect to 100 weight part of isobutylene-type polymers (A), The manufacturing method of the thermoplastic-elastomer composition of Claim 1 or 2 characterized by the above-mentioned. The process for producing a thermoplastic elastomer composition according to claim 3, wherein the softening agent (D) is paraffinic oil or polybutene. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 4, wherein the polypropylene resin (B1) is random polypropylene. The method for producing a thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the polyethylene resin (B2) is high-density polyethylene.