JP2010189604A - Highly damping composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly damping composition producing a highly damping member having damping performance improved from the present conditions while maintaining good processability. <P>SOLUTION: The highly damping composition is obtained by compounding 100 pts.mass of a base polymer with ≥100 pts.mass and ≤180 pts.mass of silica, and a rosin derivative having ≥120°C and ≤180°C softening point within the range of ≥5 pts.mass and ≤50 pts.mass. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a highly damped composition that is a source of a member that relaxes or absorbs transmission of vibration energy.

For example, the transmission of vibration energy can be eased in a wide range of fields such as buildings and bridges, industrial machinery, aircraft, automobiles, railway vehicles, computers and peripheral equipment, household electrical equipment, and automobile tires. In order to absorb, that is, to perform seismic isolation, vibration control, vibration isolation, etc., a high damping member made of an elastomer such as rubber is used.
The high damping member increases the hysteresis loss when vibration is applied and enhances the damping performance to quickly and efficiently attenuate the vibration energy, so that the elastomer is filled with a filler such as carbon black and silica, rosin, Generally, it is formed by a highly attenuated composition containing a tackifier such as petroleum resin (see, for example, Patent Documents 1 to 4). However, the damping performance of the high damping member cannot be sufficiently increased with the blending amount of the filler or tackifier described in, for example, the above-mentioned Patent Documents 1 to 4.

  In order to further improve the damping performance than the current situation, it is conceivable to increase the blending amount of a filler such as carbon black. However, in this case, the workability of the high damping composition is lowered, and a high damping member is used. There is a problem in that it is not easy to knead or mold the high attenuation composition into an arbitrary shape for manufacturing. In particular, when mass-producing high-attenuation members at the factory level, the low workability is undesirable because it reduces the productivity of high-attenuation members, increases energy consumption, and further increases production costs.

Japanese Patent No. 3593437 JP 2003-3014 A JP 2007-63425 A JP 7-41603 A

  An object of the present invention is to provide a highly attenuating composition capable of producing a highly attenuating member having improved attenuating performance as compared with the current situation while maintaining good processability.

In the present invention, 100 parts by mass of the base polymer and 100 parts by mass or more and 180 parts by mass or less of silica, and a rosin derivative having a softening point of 120 ° C. or more and 180 ° C. or less in a range of 5 parts by mass or more and 50 parts by mass or less. It is a highly attenuating composition characterized by comprising.
According to the present invention, by adding a rosin derivative having a softening point of 120 ° C. or more as a tackifier, the rosin derivative or filler can be used without adding carbon black, which is a main cause of processability deterioration, as a filler. The damping performance of the high damping member formed using the high damping composition is maintained while maintaining the blending amount of the silica as a conventional agent at the same level as the conventional one, while maintaining good processability of the high damping composition. Can be improved.

Therefore, when using the high damping composition of the present invention to form a seismic isolation damper such as a building as a high damping member, for example, by increasing the damping performance of each individual damper, The number of dampers required for the building can be reduced.
Further, according to the highly attenuated composition of the present invention, as the rosin derivative to be blended as a tackifier, by selecting and using a different softening point within the above range, the blending amount of the rosin derivative or silica can be reduced. Combined with the adjustment within the above range, the degree of freedom in designing the damping performance of the high damping member can be improved, which is advantageous in incorporating the damping performance into the design of the high damping member.

  As the base polymer, any of various base polymers that can exhibit high damping performance by blending silica and a rosin derivative can be used. However, considering that the temperature dependence of the damping performance is particularly reduced and providing a high damping member that exhibits stable damping performance over a wide temperature range, the base polymer may be natural rubber, isoprene rubber, or butadiene rubber. At least one rubber selected from the group consisting of

  ADVANTAGE OF THE INVENTION According to this invention, the high attenuation | damping composition which can manufacture the high attenuation | damping member which improved the attenuation | damping performance rather than the present condition can be provided, maintaining favorable workability.

It is a disassembled perspective view which decomposes | disassembles and shows the test body as a model of the high attenuation member produced in order to evaluate the attenuation performance of the high attenuation member which consists of the high attenuation composition of the Example of this invention, and a comparative example. FIGS. 4A and 4B are diagrams for explaining the outline of a testing machine for displacing the test body and obtaining the relationship between the displacement and the load. It is a graph which shows an example of the hysteresis loop which shows the relationship between the displacement amount and a load calculated | required by displacing a test body using the said testing machine.

In the high attenuation composition of the present invention, 100 parts by mass of the base polymer, 100 parts by mass or more and 180 parts by mass or less of silica, and 5 to 50 parts by mass of a rosin derivative having a softening point of 120 ° C. or more and 180 ° C. or less. It mix | blends in the following ranges, It is characterized by the above-mentioned.
As the base polymer, any of various base polymers that can exhibit high damping performance by blending silica and a rosin derivative, or by further vulcanizing in the case of rubber can be used, and rubber is particularly preferable.

  Examples of the rubber include natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, norbornene rubber, ethylene propylene rubber, ethylene propylene diene rubber, butyl rubber, halogenated butyl rubber, chloroprene rubber, acrylonitrile butadiene rubber, epichlorohydrin rubber, chloro One type or two or more types such as sulfonated polyethylene and polysulfide rubber may be mentioned.

In particular, considering the provision of a high damping member that exhibits stable damping performance over a wide temperature range by reducing the temperature dependence of damping performance, among these, selected from the group consisting of natural rubber, isoprene rubber, and butadiene rubber At least one kind of rubber is preferred.
As the silica, any of wet process silica and dry process silica classified by the production method may be used. Silica has a BET specific surface area of 100 to 400 m ² / g, particularly 200 to 250 m ² / g in consideration of improving the effect of improving the damping performance of the high damping member by functioning as a filler. Is preferred. The BET specific surface area is expressed by a value measured by a gas phase adsorption method using nitrogen gas as an adsorbed gas, for example, using a rapid surface area measuring device SA-1000 manufactured by Shibata Chemical Instruments Co., Ltd.

  The compounding quantity of a silica needs to be 100 mass parts or more and 180 mass parts or less per 100 mass parts of base polymers. When the blending amount is less than 100 parts by mass, the effect of improving the damping performance of the high damping member by blending silica cannot be obtained, and when it exceeds 180 parts by mass, the workability of the high damping composition is lowered. In addition, it is not easy to knead or mold the high attenuation composition into an arbitrary shape in order to produce a high attenuation member.

The amount of silica blended is 135 parts by mass or more and 180 parts by mass even within the above range in consideration of manufacturing a highly attenuating member having further improved attenuating performance while maintaining good processability of the highly attenuating composition. It is preferably less than or equal to parts.
As the rosin derivative, for example, a resin containing rosin as a constituent, such as an ester of rosin and a polyhydric alcohol (such as glycerin) or a rosin-modified maleic acid resin, which functions as a tackifier and functions as a high attenuation member Among various derivatives having an effect of improving the damping performance, those having a softening point of 120 ° C. or higher and 180 ° C. or lower are selected and used. Moreover, the compounding quantity of a rosin derivative needs to be 5 to 50 mass parts per 100 mass parts of base polymers.

When the rosin derivative having a softening point of less than 120 ° C. is blended in the range of 5 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the base polymer, the effect of improving the damping performance of the high damping member cannot be obtained. In addition, the workability of the high damping composition is lowered, and it becomes difficult to knead the high damping composition or form it into an arbitrary shape in order to produce a high damping member.
On the other hand, when a rosin derivative having a softening point exceeding 180 ° C. is blended in the range of 5 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the base polymer, the workability of the highly attenuated composition is lowered, resulting in high attenuation. In order to manufacture a member, it becomes difficult to knead the high-damping composition or form it into an arbitrary shape.

The softening point of the rosin derivative is 120 ° C. or higher and 160 ° C. even within the above range in consideration of manufacturing a high damping member with further improved damping performance while maintaining good processability of the high damping composition. It is preferable that:
If the blending amount of the rosin derivative having a softening point in the range of 120 ° C. or higher and 180 ° C. or lower is less than 5 parts by mass, the effect of improving the damping performance of the high damping member cannot be obtained. In addition, the workability of the high damping composition is lowered, and it becomes difficult to knead the high damping composition or form it into an arbitrary shape in order to produce a high damping member.

On the other hand, when the blending amount exceeds 50 parts by mass, the workability of the high damping composition is lowered, and the high damping composition is kneaded or molded into an arbitrary shape to produce a high damping member. It will not be easy to do.
In addition, the amount of the rosin derivative is 10 parts by mass or more, even within the above range, in consideration of manufacturing a high attenuation member having further improved attenuation performance while maintaining good processability of the high attenuation composition. It is preferably less than or equal to parts by mass.

The softening point is expressed by a value measured by a softening point test method (ring ball method) described in Japanese Industrial Standard JIS K2207-1996 “Petroleum Asphalt”.
Examples of rosin derivatives having a softening point in the range of 120 ° C. or higher and 180 ° C. or lower include, for example, MSR-4 (softening point: 127 ° C.), DS in the product name Harrier Star series manufactured by Harima Kasei Co., Ltd. -130 (softening point: 135 ° C), AD-130 (softening point: 135 ° C), DS-816 (softening point: 148 ° C), DS-822 (softening point: 172 ° C), manufactured by Harima Kasei Co., Ltd. One or more of 145P (softening point: 138 ° C.), 135GN (softening point: 139 ° C.), AS-5 (softening point: 165 ° C.), etc., are included in the product name Harimac series.

In addition to the above components, the high attenuation composition of the present invention may further contain other tackifiers such as petroleum resins and coumarone resins other than rosin derivatives. What is necessary is just to set the compounding quantity of the said other tackifying agent suitably according to the attenuation | damping characteristic of a high attenuation | damping member.
When the base polymer is rubber, additives such as a vulcanizing agent, a vulcanization accelerator, a vulcanization acceleration aid, and an anti-aging agent may be added to the high attenuation composition at an appropriate ratio.

The highly attenuating composition of the present invention is obtained by kneading the above components using an arbitrary kneading machine, and after molding into a predetermined shape, vulcanizing when the base polymer is rubber, A high damping member having damping characteristics can be formed.
Examples of the high-damping member that can be formed using the high-damping composition of the present invention include seismic isolation dampers incorporated in the foundation of buildings such as buildings, cable damping members such as suspension bridges and cable-stayed bridges, and industrial machinery. And anti-vibration members such as aircraft, automobiles and railway vehicles, anti-vibration members such as computers and peripheral devices, or household electric appliances, and treads for automobile tires. According to the present invention, the amount of silica to be blended in the base polymer, the softening point of the rosin derivative, the amount of the rosin derivative is adjusted within the above range, or the type of the base polymer or silica is selected. Thus, a high attenuation member having excellent attenuation performance suitable for each application can be obtained.

<Example 1>
100 parts by weight of natural rubber (SMR (Standard Malaysian Rubber) -CV60) as a base polymer, 100 parts by weight of silica (Nipsil (nip seal) KQ manufactured by Tosoh Silica Co., Ltd.), a rosin derivative (rosin modified) Maleic acid resin, softening point 139 ° C., Harima Chemical Co., Ltd. Harimac 135GN] 20 parts by mass and the following components were blended and kneaded using a closed kneader to prepare a highly attenuated composition. .

Resin: Dicyclopentadiene-based petroleum resin [softening point 105 ° C., Marukaretsu (registered trademark) M-890A manufactured by Maruzen Petrochemical Co., Ltd.] 25 parts by mass Resin: Coumarone resin [softening point 90 ° C., Nikko Chemical Co., Ltd. Manufactured by Escron (registered trademark) G-90] 10 parts by weight Anti-aging agent: benzimidazole-based anti-aging agent [2-mercaptobenzimidazole, NOCRACK (registered trademark) MB manufactured by Ouchi Shinsei Chemical Co., Ltd.] 2 parts by weight Anti-aging agent: quinone-based anti-aging agent [Antigen FR manufactured by Maruishi Chemical Co., Ltd.] 2 parts by mass Vulcanizing agent: 5% oil-treated powder sulfur [manufactured by Tsurumi Chemical Co., Ltd.] 1.58 parts by mass Accelerator: sulfenamide-based vulcanization accelerator [N-tert-butyl-2-benzothiazolylsulfenamide, Noxeller (registered trademark) NS manufactured by Ouchi Shinsei Chemical Co., Ltd.] 1 part by weight Vulcanization accelerator : Thiuram vulcanization accelerator [ Noxeller TBT-N manufactured by Ouchi Shinsei Chemical Co., Ltd. 0.7 parts by mass Vulcanization accelerating aid: 2 types of zinc oxide [Mitsui Metal Mining Co., Ltd.] 4 parts by mass Vulcanization accelerating aid: stearic acid [ "Tsubaki" manufactured by NOF Corporation] 1 part by weight <Examples 2 to 4, Comparative Examples 1 to 4>
20 parts by mass (Comparative Example 1), 40 parts by mass (Comparative Example 2), 80 parts by mass (Comparative Example 3), 135 parts by mass (Example 2), 150 parts by mass with respect to 100 parts by mass of natural rubber A highly attenuating composition was prepared in the same manner as in Example 1 except that (Example 3), 180 parts by mass (Example 4), and 225 parts by mass (Comparative Example 4) were used.

The following tests were carried out for the examples and comparative examples, and the characteristics were evaluated.
<Damping characteristic evaluation>
(Preparation of test specimen)
The highly attenuated compositions prepared in Examples and Comparative Examples were extruded into a sheet and then punched to produce a disk 1 having a thickness of 5 mm and a diameter of 25 mm as shown in FIG. Further, a highly attenuating composition for forming the disk 1 by superposing a rectangular plate-shaped steel plate 2 of thickness 6 mm × length 44 mm × width 44 mm, respectively, through a vulcanizing adhesive and heating to 150 ° C. while pressing in the laminating direction. , And the disk 1 was vulcanized and bonded to the two steel plates 2 to produce a specimen 3 for evaluating damping characteristics as a model of a high damping member.

(Displacement test)
As shown in FIG. 2 (a), two test bodies 3 are prepared, and the two test bodies 3 are fixed to one central fixing jig 4 with bolts via one steel plate 2, One left and right fixing jig 5 was fixed to the other steel plate 2 of each test body 3 with bolts. The center fixing jig 4 is fixed to the upper fixing arm 6 of the testing machine (not shown) with a bolt via a joint 7, and the two left and right fixing jigs 5 are connected to the lower movable platen of the testing machine. 8 was fixed with bolts through a joint 9.

  Next, in this state, the movable platen 8 is displaced so as to be pushed up in the direction of the fixed arm 6 as indicated by the white arrow in the drawing, and the disc 1 of the test body 3 is shown in FIG. Is deformed in a direction orthogonal to the stacking direction of the test body 3, and from this state, the movable platen 8 is pulled down in the direction opposite to the direction of the fixed arm 6 as indicated by a white arrow in the figure. The amount of displacement (mm) and load (N) when the disk 1 of the test body 3 is repeatedly strain-deformed, ie, vibrated, with the operation of returning to the state shown in FIG. Hysteresis loop H (see FIG. 3) showing the relationship between

For the measurement, the above operation was performed for 3 cycles to obtain the third value. The maximum amount of displacement was set so that the amount of deviation of the two steel plates 2 sandwiching the disc 1 in the direction perpendicular to the stacking direction was 1% of the thickness of the disc 1.
Next, a slope Keq (N / mm) of a straight line L ₁ indicated by a bold solid line in the figure connecting the maximum displacement point and the minimum displacement point in the hysteresis loop H shown in FIG. From the inclination Keq (N / mm), the thickness T (mm) of the disc 1, and the cross-sectional area A (mm ² ) of the disc 1, the formula (1):

により等価せん断弾性率Ｇｅｑ（Ｎ／ｍｍ²）を求めた。
また図３中に斜線で示した、ヒステリシスループＨの全表面積で表される吸収エネルギー量ΔＷと、同図中に網線で示した、前記直線Ｌ₁と、グラフの横軸と、直線Ｌ１とヒステリシスループＨとの交点から前記横軸におろした垂線Ｌ２とで囲まれた領域の表面積で表される弾性歪みエネルギーＷとから、式(2)：

The equivalent shear modulus Geq (N / mm ² ) was determined by
Further, the absorbed energy amount ΔW represented by the total surface area of the hysteresis loop H, indicated by diagonal lines in FIG. 3, the straight line L ₁ , the horizontal axis of the graph, and the straight line L ₁ indicated by the mesh line in FIG. From the elastic strain energy W represented by the surface area of the region surrounded by the perpendicular line L2 taken from the intersection of the hysteresis loop H and the horizontal axis, the formula (2):

により等価減衰定数Ｈｅｑを求めた。等価減衰定数Ｈｅｑが大きいほど、試験体３は減衰性能に優れていると判定できる。実施例、比較例の場合は等価減衰定数Ｈｅｑが０．３５以上であるものを減衰性能良好、０．３５未満であるものを減衰性能不足として評価した。

Thus, an equivalent damping constant Heq was obtained. It can be determined that the greater the equivalent damping constant Heq is, the better the specimen 3 is in damping performance. In the case of the example and the comparative example, the case where the equivalent attenuation constant Heq was 0.35 or more was evaluated as good attenuation performance, and the case where the equivalent attenuation constant Heq was less than 0.35 was evaluated as insufficient attenuation performance.

<Processability evaluation>
When a predetermined component is kneaded to prepare the high-attenuation compositions of Examples and Comparative Examples, and the high-attenuation composition is extruded to produce a sheet that is the basis of the disk 1 of the test body 3 In this case, it was determined whether or not the work was difficult, and the case where the work was not difficult was evaluated as good workability (◯), and the case where the work was difficult was evaluated as poor workability (×).

  The results are shown in Table 1.

表１の比較例１〜４の結果より、ベースポリマーとしての天然ゴム１００質量部に対するシリカの配合量が１００質量部未満では、高減衰部材の減衰性能が不十分であり、１８０質量部を超える場合には加工性が低下することが判った。

From the results of Comparative Examples 1 to 4 in Table 1, when the compounding amount of silica is less than 100 parts by mass with respect to 100 parts by mass of natural rubber as the base polymer, the damping performance of the high attenuation member is insufficient and exceeds 180 parts by mass. In some cases, it was found that the workability deteriorates.

On the other hand, from the results of Examples 1 to 4, when the blending amount of silica is 100 parts by mass or more and 180 parts by mass or less with respect to 100 parts by mass of natural rubber as a base polymer, good processability is maintained. However, it was confirmed that the attenuation performance could be improved compared to the current situation.
<Examples 5 to 7, Comparative Examples 5 and 6>
4 parts by mass (Comparative Example 5), 10 parts by mass (Example 5), 30 parts by mass (Example 6), 50 parts by mass (Example 7), and 55 parts by mass of Harimac 135GN with respect to 100 parts by mass of natural rubber A highly attenuating composition was prepared in the same manner as in Example 2 except that it was changed to part by mass (Comparative Example 6).

<Comparative Examples 7 and 8>
A highly attenuated composition was prepared in the same manner as in Example 2 except that the same amount of xylene resin (Comparative Example 7) and asphalt (Comparative Example 8) were blended in place of the rosin derivative.
Each of the above-mentioned examples and comparative examples was subjected to the previous tests, and their characteristics were evaluated. The results are shown in Table 2 together with the results of Example 2.

表２の比較例５、６の結果より、ベースポリマーとしての天然ゴム１００質量部に対するロジン誘導体の配合量が５質量部未満では、高減衰部材の減衰性能が不十分で、しかも加工性が低下し、５０質量部を超える場合には加工性が低下することが判った。

From the results of Comparative Examples 5 and 6 in Table 2, when the blending amount of the rosin derivative with respect to 100 parts by mass of the natural rubber as the base polymer is less than 5 parts by mass, the damping performance of the high damping member is insufficient and the processability is lowered. And when it exceeded 50 mass parts, it turned out that workability falls.

Further, from the results of Comparative Examples 7 and 8, when the xylene resin was blended instead of the rosin derivative, the workability deteriorated, and when the asphalt was blended, the damping performance of the high damping member was insufficient, and the workability Was found to be reduced.
On the other hand, from the results of Examples 2 and 5-7, the rosin derivative was blended in place of xylene resin and asphalt, and the blending amount of the rosin derivative with respect to 100 parts by mass of the natural rubber as the base polymer was 5 parts by mass or more. It was confirmed that the damping performance can be improved as compared with the current situation while maintaining good workability when the content is within the range of 50 parts by mass or less.

<Comparative Example 9>
Instead of Harimac 135GN, a rosin derivative having a softening point of 71 ° C. (rosin-modified glycerin ester, softening point 71 ° C., Harrier Star S manufactured by Harima Chemical Co., Ltd.) was mixed in the same manner as in Example 2. A highly attenuated composition was prepared.
<Comparative Example 10>
Instead of Harimac 135GN, the same amount of rosin derivative (rosin ester resin, softening point 90 ° C., Harrier Star K-90 manufactured by Harima Chemical Co., Ltd.) having a softening point of 90 ° C. was blended in the same manner as in Example 2. A highly attenuated composition was prepared.

<Comparative Example 11>
Example 2 except that the same amount of rosin derivative (rosin-modified maleic acid resin, softening point 101 ° C., Harima Chemical Co., Ltd. Harimac R-100) having a softening point of 101 ° C. was used instead of Harimac 135GN. A highly attenuated composition was prepared as follows.
<Comparative example 12>
Instead of Harimac 135GN, a rosin derivative having a softening point of 102 ° C. (rosin ester, softening point of 102 ° C., Harrier Chemical Co., Ltd. Harrier Star SP-100) was blended in the same amount as in Example 2. A highly attenuated composition was prepared.

<Example 8>
Example 2 except that the same amount of a rosin derivative having a softening point of 127 ° C. (rosin-modified special synthetic resin, softening point of 127 ° C., Harrier Star MSR-4 manufactured by Harima Chemical Co., Ltd.) was used instead of Harimac 135GN. Similarly, a highly attenuated composition was prepared.
<Example 9>
Example 2 except that the same amount of a rosin derivative having a softening point of 135 ° C. (rosin-modified special synthetic resin, softening point of 135 ° C., Harrier Star DS-130 manufactured by Harima Chemical Co., Ltd.) was used instead of Harimac 135GN. Similarly, a highly attenuated composition was prepared.

<Example 10>
Instead of Harimac 135GN, a rosin derivative having a softening point of 148 ° C. (rosin ester, softening point of 148 ° C., Harrier Chemicals Co., Ltd. Harrier Star DS-816) was used in the same manner as in Example 1, except that the same amount was blended. A highly attenuated composition was prepared.
<Example 14>
Instead of Harimac 135GN, a rosin derivative having a softening point of 172 ° C. (rosin ester, softening point of 172 ° C., Haristar Kasei Co., Ltd. Harrier Star DS-822) was used in the same manner as in Example 1 except that it was blended in the same amount. A highly attenuated composition was prepared.

<Comparative Example 13>
Example 1 except that the same amount of a rosin derivative having a softening point of 183 ° C. (rosin-modified special synthetic resin, softening point of 183 ° C., Harrier Star KT-2 manufactured by Harima Chemical Co., Ltd.) was used instead of Harimac 135GN. Similarly, a highly attenuated composition was prepared.
Each of the above-mentioned examples and comparative examples was subjected to the previous tests, and their characteristics were evaluated. The results are shown in Tables 3 and 4 together with the results of Example 2.

表３の比較例９〜１２の結果より、ロジン誘導体として軟化点が１２０℃未満であるものを用いた場合には、高減衰部材の減衰性能が不十分になったり、加工性が低下したりすることが判った。

From the results of Comparative Examples 9 to 12 in Table 3, when a rosin derivative having a softening point of less than 120 ° C. is used, the damping performance of the high damping member becomes insufficient, or the workability decreases. I found out that

Further, from the results of Comparative Example 13, it was found that when a rosin derivative having a softening point exceeding 180 ° C. was used, the workability was lowered.
On the other hand, from the results of Examples 2 and 9 to 11, if a rosin derivative having a softening point of 120 ° C. or higher and 180 ° C. or lower is used, the damping performance is better than the current state while maintaining good processability. It was confirmed that it could be improved.

DESCRIPTION OF SYMBOLS 1 Disc 2 Steel plate 3 Test body 4 Center fixing jig 5 Left and right fixing jig 6 Fixed arm 7 Joint 8 Movable platen 9 Joint

Claims (2)

  100 parts by mass of the base polymer and 100 parts by mass or more and 180 parts by mass or less of silica, and a rosin derivative having a softening point of 120 ° C. or more and 180 ° C. or less in a range of 5 parts by mass or more and 50 parts by mass or less. A highly attenuated composition characterized by   2. The high damping composition according to claim 1, wherein the base polymer is at least one rubber selected from the group consisting of natural rubber, isoprene rubber, and butadiene rubber.

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