JP2000169523A - Polyisobutylene polymer and rubber composition containing same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyisobutylene polymer having improved reinforcing properties and showing improved viscoetasticity and abrasion resistance when used as a stock rubber for tires, which polymer has an alkoxysilane and a moiety capable of hydrogen bonding in the molecule and at least comprises isobutyelene as the monomer. SOLUTION: An alkoxysilane and a compound having at least one group capable of hydrogen bonding, selected from among a carboxyl group, an amido group, an ester group, a hydroxyl group, and an amino group are introduced into the terminal or inner part of the molecule by a known method to obtain a modified polyisobutylene polymer having a structure represented by the formula at the inner or terminal part of the molecule. In the formula, R1 is a 1-18C hydrocarbon group; R2, R3, and R4 are each a 1-18C hydrocarbon group or an alkoxyl; and R5 is hydrogen or a 1-18C hydrocarbon group. To form a rubber composition, 100 pts.wt. diene stock rubber is blended with 1-100 pts.wt. modified polyisobutylene polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified polyisobutylene polymer and a rubber composition containing the same, and more particularly, to a modified polyisobutylene polymer having improved viscoelastic properties and abrasion resistance, and a modified polyisobutylene polymer. And a rubber composition containing the same.

[0002]

2. Description of the Related Art Butyl rubber has a high ta in a wide temperature range.
Since it exhibits nδ, it exhibits high grip performance. In particular, since tan δ at 0 ° C. is high, it is expected that wet performance is improved. However, since there are few double bonds, there is a problem that reinforcement by crosslinking and reinforcement by filler are low.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to eliminate the above-mentioned problems of the conventional butyl rubber,
It is an object of the present invention to provide a modified polyisobutylene-based polymer which is useful for a tire having improved viscoelasticity and abrasion resistance while improving the reinforcing property, and a rubber composition containing the same.

[0004]

According to the present invention, an alkoxysilane and at least one site capable of hydrogen bonding selected from the group consisting of a carboxylic acid, an amide, an ester, a hydroxyl group and an amino group are present in the molecule. And a polymer having at least one isobutylene as a monomer.

According to the present invention, there is also provided a compound having at least one site capable of hydrogen bonding selected from the group consisting of a carboxylic acid, an amide, an ester, a hydroxyl group and an amino group. And a polymer having at least one isobutylene as a monomer.

According to the present invention, there is also provided a polymer having an alkoxysilane, a carboxylic acid and an amide in a molecule and having at least one kind of isobutylene as a monomer.

According to the present invention, there is provided a polymer having at least one kind of isobutylene as a monomer and having a structure represented by the following formula (I) in a molecule or at a terminal.

Embedded image(Where R₁, R_Two, R_ThreeAnd R_FourAre the same
May be different, R ₁Represents 1 to 18 carbon atoms
Having a hydrocarbon group, R_Two, R_ThreeAnd R_FourIs 1-18
Hydrocarbon group having 1 to 18 carbon atoms or 1 to 18 carbon atoms
An alkoxyl group having a hydrogen atom;
_FiveIs hydrogen or a hydrocarbon having 1 to 18 carbon atoms
Represents an elementary group. )

According to the present invention, there is provided a rubber composition comprising at least one of the above polymers.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the reinforcing property with a filler is improved by introducing an alkoxysilane into the terminal or in the molecule of polyisobutylene, and at the same time, a site capable of hydrogen bonding in the molecule (carboxylic acid, amide or the like). ,ester,
When a reinforcing property was achieved by introducing pseudo-crosslinking between rubbers by introducing a hydroxyl group or an amino group), it was found that there was an effect of improving viscoelastic properties and abrasion resistance.

The polymer having at least one isobutylene used as a monomer in the present invention includes polyisobutylene, polybutene, butyl rubber, brominated butyl rubber, isobutylene / maleic anhydride copolymer, isobutylene / p-methylstyrene / p-butylene. Bromomethylstyrene copolymers and the like can be mentioned, and these can be used alone or as a mixture of two or more.

The modified polyisobutylene polymer according to the present invention is characterized in that the above-mentioned polymer having at least one kind of isobutylene as a monomer has alkoxysilane and a carboxylic acid, an amide, an ester, a hydroxyl group, an amino group or the like hydrogen bond at the terminal or in the molecule. A given compound having at least one possible group can be obtained by introduction using methods well known in the art.

Typical modified polyisobutylene polymers of the present invention include the following polymers.

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[0013]

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[0014]

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[0015]

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[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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[0021]

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(Note) In the above formula, Et: -C ₂ H ₅ (ethyl group), Me: -CH ₃ (methyl group), Ph: -C ₆ H
₅ represents a (phenyl group).

The modified polyisobutylene polymer of the present invention comprises
Conventionally, a rubber generally used as a rubber composition, particularly preferably 1 to 100 parts by weight of a diene-based raw rubber is preferably used.
100 parts by weight, more preferably 10 to 50 parts by weight can be blended. If the amount is too small, the effects of the present invention will not be obtained, which is not preferable.

The rubber compounded as the main component in the rubber composition according to the present invention may be any diene rubber conventionally compounded in various rubber compositions, for example, natural rubber (N
R), polyisoprene rubber (IR), various styrene-butadiene copolymer rubbers (SBR), various polybutadiene rubbers (BR), acrylonitrile-butadiene copolymer rubber (NBR), and diene rubbers such as butyl rubber (IIR). It can be used alone or as any blend.

The rubber composition according to the present invention further contains a general reinforcing agent. Examples of the reinforcing agent include carbon black and silica.
40 parts by weight or more, preferably 50 to 120 parts by weight, of a reinforcing agent is added to 0 parts by weight. If the amount is too small, the reinforcing properties required for the rubber composition cannot be obtained, which is not preferable.

In the rubber composition according to the present invention, in addition to the above essential components, a vulcanizing or crosslinking agent, a vulcanizing or crosslinking accelerator, various oils, an antioxidant, a plasticizer, etc. Various additives generally compounded for rubber can be compounded, and such a compound can be kneaded and vulcanized into a composition by a general method and used for vulcanization or crosslinking. it can. The compounding amounts of these additives can also be conventional general compounding amounts as long as they do not contradict the object of the present invention.

[0027]

EXAMPLES The present invention will be further described below with reference to Examples and Comparative Examples, but it goes without saying that the scope of the present invention is not limited to these Examples.

Examples 1-2 and Comparative Examples 1-4 ( Examples of synthesis of modified polybutene) 100 g of maleated polybutene (number average molecular weight 2,900, maleation ratio 70%, (Nippon Petrochemical)) and 3-amino Propyltrimethoxysilane (Nippon Unicar A1110) 9.13
g (0.0509 mol) was synthesized by heating and stirring at 80 ° C. for 12 hours. When IR analysis of the reaction product was performed,
Absorption of the carbonyl of 1715 cm ^-1 is shifted to 1738 cm ^-1, it was confirmed that the following reaction proceeds.

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Preparation of Test Samples In the formulation shown in Table I, the components other than the vulcanization accelerator and sulfur were kneaded in a 1.8-liter closed mixer for 3 to 5 minutes, and when the temperature reached 165 ± 5 ° C. The released masterbatch was kneaded with an 8-inch open roll with a vulcanization accelerator and sulfur to obtain a rubber composition. The unvulcanized physical properties (Mooney viscosity) of the obtained rubber composition were measured. Next, this composition is
Press vulcanization at 160 ° C. for 20 minutes in a mold of 5 × 15 × 0.2 cm to prepare a target test piece (rubber sheet),
The vulcanization properties (stretch viscoelasticity, wear resistance) were evaluated.

The test method used for the above measurement and evaluation is as follows:
It is as follows. Unvulcanized properties 1) Mooney viscosity: 100 based on JIS K6300
Measured at ° C. Vulcanization properties 2) tan δ (0 ° C. and 60 ° C.): Using a rheograph solid manufactured by Toyo Seiki Seisaku-sho, viscoelasticity was measured at an initial strain of 10%, a dynamic strain of 2%, and a frequency of 20 Hz (sample width:
5mm). 3) Abrasion resistance: Abrasion loss was measured using a Lambourn abrasion tester (manufactured by Iwamoto Seisakusho Co., Ltd.) at a temperature of 20 ° C. and a slip rate of 50%. The larger the value, the better the wear resistance.

The results are shown in Table I.

[Table 1]

From the results shown in Table I, the rubber compositions containing the modified polybutene according to the present invention (Examples 1 and 2) were the same as the rubber compositions containing the maleated polybutene of the conventional example (Comparative Examples 2 and 4). ) And rubber compositions not containing any of these (Comparative Examples 1 and 3), have excellent Mooney viscosity, excellent tan δ balance, and greatly improved abrasion resistance. Understand.

[0033]

As described above, the rubber composition containing the alkoxysilane according to the present invention and the polymer introduced so as to have a hydrogen bondable site in the molecule or at the end thereof is obtained. Although the abrasion is improved, it is useful as a rubber composition for tires and the like.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J002 AC00W AC01W AC05W AC06W AC08W BB18W BB18X BB20X BB21X DA030 DJ010 FD010 GN01 4J100 AA04P AA05P AA06P AB04Q AB09R AK32Q CA01 CA04 CA05 CA31 HC77 HC78

Claims (6)

[Claims] Claims: 1. An alkoxysilane having at least one hydrogen bondable site selected from the group consisting of a carboxylic acid, an amide, an ester, a hydroxyl group and an amino group in a molecule thereof, and at least one type of isobutylene as a monomer. Having a polymer. 2. A compound having an alkoxysilane at its terminal, having at least one site capable of hydrogen bonding selected from the group consisting of a carboxylic acid, an amide, an ester, a hydroxyl group and an amino group in a molecule, and isobutylene as a monomer. A polymer having at least one kind. 3. A polymer having an alkoxysilane, a carboxylic acid and an amide in a molecule and having at least one kind of isobutylene as a monomer. 4. Isobutylene as a monomer at least
And has a structure represented by the following formula (I) in the molecule.
Polymer. Embedded image(Where R₁, R_Two, R_ThreeAnd R_FourAre the same
May be different, R ₁Represents 1 to 18 carbon atoms
Having a hydrocarbon group, R_Two, R_ThreeAnd R_FourIs 1-18
Hydrocarbon group having 1 to 18 carbon atoms or 1 to 18 carbon atoms
An alkoxyl group having a hydrogen atom;
_FiveIs hydrogen or a hydrocarbon having 1 to 18 carbon atoms
Represents an elementary group. ) 5. A polymer having at least one isobutylene as a monomer and having a terminal represented by the following formula (I). Embedded image (Wherein R ₁ , R ₂ , R ₃ and R ₄ may be the same or different, and R ₁ is a hydrocarbon group having 1 to 18 carbon atoms, R ₂ , R ₃ And R ₄ is 1 to 1
It represents eight hydrocarbon group or 1 to 18 alkoxyl groups having a carbon atom having carbon atoms, and R ₅
Represents hydrogen or a hydrocarbon group having 1 to 18 carbon atoms. ) 6. A rubber composition comprising at least one polymer according to any one of claims 1 to 5.