JPH062844B2 - Anti-vibration rubber composition - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration rubber composition, and more particularly to a rubber composition having a small dynamic magnification used for automobile strut mounts, link bushes and the like. is there.

2. Description of the Related Art Conventionally, as this type of anti-vibration rubber composition, natural rubber is mixed with diene rubber such as butadiene rubber, and further zinc white, stearic acid, carbon black, vulcanizing agent, vulcanization accelerator, etc. A blended product is used, and by increasing the addition amount of the vulcanizing agent, the hardness and the dynamic ratio are reduced.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a conventional example, when the amount of the vulcanizing agent added is excessive, not only the physical properties of the rubber are deteriorated but also the molding processability is significantly deteriorated. Was there.

The present invention was devised in view of such conventional problems, and has a vibration-proof rubber composition having an appropriate vulcanization rate, and achieving high speed and low dynamic ratio. It is what you get.

MEANS FOR SOLVING THE PROBLEMS The present invention relates to isoprene rubber containing 0 to 7 diene-based synthetic rubber.
0.5 to 4 parts by weight of zinc methacrylate based on 100 parts by weight of raw rubber containing 0 parts by weight, n = 2 to 12, a methylenediamine compound represented by a rational formula of 0.5 to
The compounding of 4 parts by weight is the solution.

Examples Hereinafter, details of the anti-vibration rubber composition according to the present invention will be described based on examples.

The rubber material used in the anti-vibration rubber composition of the present invention is isoprene rubber and diene-based synthetic rubber. As the diene-based synthetic rubber, for example, butadiene rubber or styrene-butadiene rubber is selected.

The anti-vibration rubber of the present invention contains 0.5 to 4 parts by weight of zinc methacrylate and 0. 4 parts by weight of a methylenediamine compound based on 100 parts by weight of a raw rubber containing 0 to 70 parts by weight of a diene synthetic rubber in isoprene rubber. It is composed of 5 to 4 parts by weight.

The methylenediamine-based compound has the following rational formula It has a structure represented by n = 2 to 12.

Furthermore, zinc rubber, stearic acid, carbon black, a softening agent, a vulcanization accelerator, and a vulcanizing agent are blended with the anti-vibration rubber of the present invention.

It should be noted that zinc methacrylate and methylenediamine compounds can achieve a high concentration and low dynamic magnification (low loss factor) to some extent even if one of them is blended, but when used in combination, a synergistic property improving effect is obtained. To be

Further, when only one of the chemicals is blended, the accelerated particle size changes remarkably, and therefore a sufficient effect can be obtained only by using zinc methacrylate and a methylenediamine compound in combination.

Examples 1 and 2, Comparative Examples 1 to 4 Curast vulcanization characteristics, vibration characteristics, and hardness (JII.
A) was measured. The results are shown in the lower part of Table 1.

In addition, the Curast vulcanization characteristics are measured at a measurement temperature of 150 ° C.
It was measured using SR Curastometer Model III.

Further, the vibration characteristic is 40 mm × 4 as shown in FIG.
Using a rectangular anti-vibration rubber test piece A formed in a 0 mm x 30 mm rectangular parallelepiped, the static spring constant is 2 to 4 mm in the compression direction.
Measured between. The dynamic spring constant is measured at 3 mm compression ± 1 mm at 10 Hz and 3 mm compression ± 0.0 at 100 Hz.
It was measured at 5 mm.

As a result, compared to Comparative Example, the vibration-proof rubber composition of the present invention,
It was confirmed that the hardness was high and the dynamic magnification (loss factor) was small.

Further, the following Table 2 shows the results of measurement of axial characteristics and torsional hysteresis (Kg · m) using the automotive upper link bush B as shown in FIG.

As a result, in the embodiment of the present invention, the static spring constant,
10 Hz dynamic spring constant, 100 Hz dynamic spring constant, 10
It was confirmed that both the Hz loss factor and the torsional hysteresis were low.

EFFECTS OF THE INVENTION As is clear from the above description, in the vibration-insulating rubber composition according to the present invention, it is possible to prepare a material having high hardness and low dynamic magnification (low loss factor), which has been difficult to design by conventional materials. Has the effect of enabling. Therefore, if a machine or device that requires a vibration damping function, particularly a strut mount, a link bush, or the like used in an automobile, is made of the present composition, it has the effect of improving the performance.

[Brief description of drawings]

FIG. 1 is a perspective view showing a square vibration-proof test piece, and FIG. 2 is a sectional view of an upper link bush.

Claims (1)

[Claims] 1. A diene-based synthetic rubber is added to isoprene rubber in an amount of 0 to
0.5 to 4 parts by weight of zinc methacrylate based on 100 parts by weight of the raw rubber containing 70 parts by weight, n = 2 to 12, a methylenediamine compound represented by a rational formula of 0.5 to
An anti-vibration rubber composition containing 4 parts by weight of the anti-vibration rubber composition.