JP2002265691A - Vibration proof rubber composition and vibration proof rubber using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vibration proof rubber composition capable of reducing the frictional coefficient of the surface of a rubber blended product to a great extent even under atmosphere having a wide range of temperatures ranging from a low temperature (10 deg.C) to a high temperature (50 deg.C), thus, suppressing the generation of abnormal noises causes by stick slip phenomena in a wide temperature range even under a circumstance for using in a lot of abrasion such as a stabilizer bush and the like and provide a vibration proof rubber. SOLUTION: This vibrationproof rubber composition is prepared by blending 2-25 pts.wt. petroleum-based wax having a carbon number distribution with two peaks of a lower molecular weight component region and a higher molecular weight component region with the Cmax of the lower molecular weight component region in C24 -C29 and the Cmax of the higher molecular weight component region in C32 -C38 to 100 pts.wt. of a rubber component. This vibrationproof rubber is prepared by using the aforesaid vibrationproof rubber composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration rubber composition capable of suppressing abnormal noise generated in an anti-vibration rubber part used in a vehicle such as an automobile, and an anti-vibration rubber using the same. is there. More specifically, the present invention relates to an anti-vibration rubber composition and an anti-vibration rubber suitable for applications such as a stabilizer bush and a rear suspension bush of an automobile.

[0002]

2. Description of the Related Art Anti-vibration rubbers for automobiles, for example, rubber vibration absorbers used by fitting metal parts such as a stabilizer bush and a rear suspension bush, are used when starting or suddenly braking, and when turning left and right. At times and the like, abnormal noise is generated due to the stick-slip phenomenon at the contact portion between the mounting bracket and the surface of the rubber bush.

[0003] As a countermeasure, various methods for reducing the friction coefficient of the surface of the rubber compound have been studied. For example,
A method of adding a wax to a rubber component, a method of adding a liquid silicone oil, and the like have been proposed. However, even if wax is added or a certain fatty acid amide is used in combination to achieve a low coefficient of friction, the temperature is from normal temperature (25 ° C.) to a high temperature side (50 ° C.) or from normal temperature to a low temperature side (10 ° C.).
There is a problem that the effect of reducing frictional resistance can be obtained only in a very narrow temperature range of (° C).

That is, in many cases, a sufficient effect of reducing frictional resistance cannot be obtained at low or high temperatures. Also,
Although the method of adding silicone oil has an excellent effect in reducing the coefficient of friction, it has a problem that compatibility with the rubber component is poor, kneading processability is remarkably inferior, and mass production is difficult.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem, and to provide a vibration-proof rubber composition having a significantly reduced friction coefficient in a wide temperature atmosphere at both low and high temperatures and excellent in workability in production. An object and an anti-vibration rubber using the same are provided.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, only a low molecular weight component of the compounded wax blooms on the surface of the rubber compound under a low-temperature atmosphere, and this blooming film has a low temperature. In high temperature atmosphere, only the high molecular weight component of the compounded wax blooms on the surface of the rubber compound, and it was found that this blooming film reduced the coefficient of friction in high temperature atmosphere. .

[0007] Further, the low molecular weight component of the compounded wax that has bloomed on the surface of the rubber compound in a low-temperature atmosphere has re-melted into the compounded rubber in a high-temperature atmosphere and conversely has bloomed on the surface of the rubber compound in a high-temperature atmosphere. It has been found that the high molecular weight component of the compounded wax remelts into the compounded rubber under a low-temperature atmosphere.

Accordingly, by blending a rubber containing a wax component having a high molecular weight and a low molecular weight that is sufficient to bloom on the rubber surface at a low temperature to a high temperature, the rubber is excellent in a predetermined atmosphere temperature range from a low temperature to a high temperature. It has been confirmed that the present invention exerts the effect of reducing the friction coefficient, and the present invention has been completed.

That is, according to the present invention, a petroleum wax having a carbon number distribution of two peaks in a low molecular weight region and a high molecular weight region is added to 100 parts by weight of a rubber component so as to form a blooming film at a predetermined atmospheric temperature. The present invention relates to an anti-vibration rubber composition containing up to 25 parts by weight and an anti-vibration rubber using the same.

[0010]

DETAILED DESCRIPTION OF THE INVENTION As a petroleum wax in the present invention, microcrystalline wax and paraffin wax are used.
Two or more high molecular weight waxes may be individually mixed, and any petroleum wax having a carbon number distribution of two peaks of a high molecular weight component region and a low molecular weight component region that finally blooms in a predetermined atmosphere may be used. .

The compounding amount is based on 100 parts by weight of the rubber component.
Use 2 to 25 parts by weight. If the amount is less than 2 parts by weight, the effect of reducing the friction coefficient is not sufficient, and if it exceeds 25 parts by weight, the effect of increasing the amount is no longer recognized.

As the petroleum wax having two peaks of carbon number distribution, Cmax of the low molecular weight component is C _{24 to} C ₂₉ ,
Waxes are preferred Cmax of the high molecular weight component is a _C 32 _{-C 38.} That is, with respect to the reduction of the coefficient of friction under a low-temperature atmosphere (10 ° C.), if Cmax is 23 or less, the molecular weight is too low and there is no effect of reducing the coefficient of friction. There is no effect of reducing the coefficient of friction at low temperatures. In addition, with respect to the reduction of the friction coefficient under a high temperature atmosphere (50 ° C.), the effect of reducing the friction coefficient at a high temperature is ineffective at Cmax 31 or less due to the low molecular weight, and conversely, at a value of 39 or higher, the molecular weight is too high to reduce the friction coefficient. No reduction effect.

In the present invention, the rubber components include butadiene rubber (BR) and styrene-butadiene rubber (SB).
R), nitrile rubber (NBR), isoprene rubber (I
R), diene rubbers such as chloroprene rubber (CR), olefin rubbers such as ethylene propylene rubber (EPR, EPDM) and butyl rubber (IIR), halogenated butyl rubbers such as brominated butyl rubber (Br-IIR), and other polyurethane rubbers Synthetic rubbers including acrylic rubber, fluorine rubber, silicone rubber, chlorosulfonated polyethylene, etc., and natural rubber are exemplified, and these can be used alone or in combination of two or more.

In the rubber composition of the present invention, in addition to the above essential components, a vulcanization accelerator, a reinforcing agent, a vulcanization aid, a softening agent, a processing aid conventionally used as an additive for rubbers. , An anti-aging agent, a filler and the like can be blended within a usual range as required.

The rubber composition of the present invention can be obtained by kneading these components with a usual processing device, for example, a roll, a Banbury mixer, a kneader or the like. The vibration-proof rubber can be obtained by vulcanizing this rubber composition by a known method.

The anti-vibration rubber of the present invention obtained as described above,
Although it can be preferably used for a fitting bush such as a stabilizer bush, it can also be used for a portion where a metal and rubber are in contact with each other without being fixed and adhered, and a rotational force or a load is applied.

[0017]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited by these descriptions.

(Examples 1 to 5 and Comparative Examples 1 to 6) Natural rubber, butadiene rubber, FEF carbon black, petroleum wax and additives were blended as shown in Table 1. The anti-vibration rubber compositions of Examples 1 to 5 were prepared.

The above additives are 3 parts by weight of an aroma-based process oil, 5 parts by weight of Zinhua No. 3, 1 part by weight of stearic acid, 2 parts by weight of an antioxidant 6C (manufactured by Ouchi Shinko Chemical Co., Ltd.), 2 parts by weight of antioxidant RD (manufactured by Ouchi Shinko Chemical Co., Ltd.)
1.5 parts by weight of sulfur, vulcanization accelerator CZ (Ouchi Shinko Chemical Co., Ltd.)
1.5 parts by weight, vulcanization accelerator TS (Ouchi Shinko Chemical Co., Ltd.)
0.5 parts by weight.

The above rubber composition was formed into a stabilizer bush shape and vulcanized at 150 ° C. for 30 minutes, and the presence or absence of abnormal noise was evaluated by a tester shown in FIG. That is, the stabilizer bush 3 shown in FIG.
Is loaded with a metal stabilizer bar 2, and the stabilizer bush 3 is tightened with a clamp, and the bar 2 is
Degree torsion, then the presence or absence of abnormal noise at 10 ° C and 50 ° C
The temperature was checked at ° C, and those in which no abnormal noise was generated were evaluated as “○”, and those in which abnormal noise was generated were evaluated as “x”.

The petroleum waxes A to F in Table 1 are:
Cmax in carbon number distribution is a microcrystalline wax having a two-peak peak takes a value of each table 2 with a low molecular weight component and a high molecular weight component, petroleum wax G is, Cmax in the carbon number distribution is C ₃₇ 1 It is a microcrystalline wax at the peak of the mountain. The carbon number distribution was measured by an analysis method using gas chromatography, and the analysis conditions were as follows. Model: YANA Co. G-80, Detector: FID Column: Silicon OV-1 (3%) 0.75m Glass Chromosolve WAW, DMCS 60-80 mesh

As is evident from Table 1, Examples 1 to 5 have a balanced noise at both low temperature (10 ° C) and high temperature (50 ° C) compared to Comparative Examples 1 to 6. Demonstrates the effect of prevention.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

As described above, according to the present invention, a low-temperature (10 ° C.) and high-temperature (50 ° C.)
(C), a vibration-proof rubber composition and a vibration-proof rubber exhibiting a well-balanced friction coefficient reduction effect can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a stabilizer bush.

[Explanation of symbols]

 3 Stabilizer bush 2 Stabilizer bar 1 Through hole

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shuji Fujino 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Toyo Tire & Rubber Co., Ltd. F-term (reference) 3J048 AA01 BA05 BA19 DA01 DA06 EA36 4J002 AC031 AC061 AC071 AC081 AC091 AC121 AE032 BB151 BB181 BB271 BG041 CK021 CP031 GN00

Claims (2)

[Claims] 1. A the rubber component 100 parts by weight, has a carbon number distribution of the two mountains of low molecular weight component region and the high molecular weight component region, Cmax of the low molecular weight component area C _{24 -C 29,}
Vibration damping rubber composition Cmax of the high molecular weight component region petroleum wax is a _C 32 _{-C 38,} characterized by compounding 2-25 parts by weight. 2. An anti-vibration rubber comprising the anti-vibration rubber composition according to claim 1.