JP2011132481A - High damping composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high damping composition solving a problem of temperature dependency and forming a high damping member with damping performance higher than a current one while maintaining good workability. <P>SOLUTION: The high damping composition comprises a diene-based polymer having no polar group, a liquid copolymer having a butadiene skeleton, and a rosin derivative. As the liquid copolymer, at least one selected from the group consisting of a liquid acrylonitrile-butadiene rubber, a liquid isoprene-butadiene rubber, and a liquid styrene-butadiene rubber is preferable. The high damping composition may comprises 100-180 pts.mass of silica per 100 pts.mass of the diene-based polymer; and 10-20 pts.mass of a silane compound per 100 pts.mass of the silica. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

For example, 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, vibration energy transmission is alleviated. In order to absorb or absorb, that is, to perform seismic isolation, vibration control, vibration control, vibration isolation, etc., a high damping member containing rubber or the like as a base polymer is used.
The high-damping member increases the hysteresis loss when vibration is applied and enhances the damping performance to attenuate the vibration energy efficiently and quickly, so that the elastomer is filled with a filler such as carbon black or silica (patent document) 1), or a high damping composition containing a tackifier such as rosin or petroleum resin or a softener such as aroma oil.

  However, these conventional high damping compositions cannot sufficiently enhance the damping performance of the high damping member. In order to further improve the damping performance of the high-damping member, it may be possible to further increase the content ratio of the filler, for example, but a high-damping composition containing a large amount of filler or tackifier There is a problem in that the workability is deteriorated, and it is not easy to knead or mold the high attenuation composition into the three-dimensional shape in order to produce a high attenuation member having a desired three-dimensional shape. .

Especially when producing high-attenuation members in large quantities at the factory level, the low workability decreases the productivity of the high-attenuation members, increases the energy consumption required for production, and further increases the production cost. Therefore, it is not desirable.
Further, as a highly attenuating composition, a base polymer having a polar side chain containing a hindered phenol-based attenuating agent having two or more polar groups is also known (Patent Document 2, etc.).

  However, since the base polymer having a polar group in the molecule, such as that described in Patent Document 2, generally has a glass transition temperature Tg near room temperature (3 to 35 ° C.), a high damping composition containing the base polymer. A high damping member formed using an object tends to increase the temperature dependency of characteristics such as rigidity in the vicinity of the room temperature, which is the most common operating temperature range. For this reason, there is a problem that it is difficult to system design a high damping member while incorporating such characteristics.

In recent years, considering the impact on the environment, it has been studied to contain liquid isoprene rubber, liquid styrene-isoprene rubber, etc. as a softening agent instead of aromatic oils that may contain polycyclic aromatic hydrocarbons. (Patent Document 3 etc.).
However, the liquid isoprene rubber and the like mentioned in Patent Document 3 cannot contribute to the improvement of the damping performance of the high damping member. It is only a thing which can be used as a substitute for an aroma-based oil.

JP 7-41603 A JP 2000-44813 A JP 2009-30016 A

  An object of the present invention is to provide a highly attenuating composition that can form a highly attenuating member that is more excellent in attenuating performance than the current state while eliminating the problem of temperature dependence and maintaining good workability. is there.

The present invention is a high attenuation composition comprising a diene base polymer having no polar group, a liquid copolymer having a butadiene skeleton, and a rosin derivative.
According to the present invention, by selecting and using a diene base polymer that does not have a polar group as the base polymer, the temperature dependency of the characteristics of the high attenuation member near the room temperature is reduced, and the temperature dependency problem is reduced. Can be resolved. Therefore, it is possible to form a high damping member that exhibits stable damping performance over a wide temperature range.

  According to the present invention, a liquid copolymer having a butadiene skeleton is selectively used in combination with the diene base polymer as a softener instead of the aroma oil or liquid isoprene rubber, and a rosin derivative is further used. By adding, the damping performance of the high damping member can be greatly improved, as is apparent from the results of Examples and Comparative Examples described later.

Moreover, since the liquid copolymer is excellent in the function of improving the damping performance of the high damping member, it is not necessary to increase the content ratio when silica or the like is contained as a damping property imparting agent, and the liquid copolymer is used as a softening agent. Due to the synergistic effect of functioning well, the processability of the highly attenuated composition can also be improved.
Therefore, according to the highly attenuating composition of the present invention, it is possible to form a highly attenuating member that is more excellent in attenuating performance than the current state while eliminating the temperature dependency problem and maintaining good workability. Become.

Therefore, for example, when forming the damping damper for a building as a high damping member using the high damping composition of the present invention as a forming material, the quantity of the damping damper incorporated in one building Can be reduced. In addition, since the temperature dependency is small, for example, the damping damper can be installed near the outer wall of a building having a large temperature difference.
As the liquid copolymer, at least selected from the group consisting of liquid acrylonitrile-butadiene rubber, liquid isoprene-butadiene rubber, and liquid styrene-butadiene rubber, which are excellent in the effect of improving the damping performance and can also function well as a softening agent. One is preferred. The diene base polymer having no polar group is preferably a natural rubber which is easily available and can form a high attenuation composition at low cost.

The high attenuation composition of the present invention preferably contains 100 parts by mass or more and 180 parts by mass or less of silica per 100 parts by mass of the diene base polymer. Since the silica functions as an attenuation imparting agent as described above, the attenuation performance of the high attenuation member can be further improved.
Moreover, it is preferable that the high attenuation | damping composition of this invention also contains 10 mass parts or more and 20 mass parts or less of silane compounds per 100 mass parts of said silica. The silane compound functions as a dispersant for improving the affinity and compatibility of the silica with organic components such as diene-based polymers and liquid copolymers. Therefore, silica can be made to function more satisfactorily as an attenuating agent in the high attenuation member, and the attenuation performance of the high attenuation member can be further improved.

  According to the present invention, it is possible to provide a highly attenuating composition that can form a highly attenuating member that is more excellent in attenuating performance than the current state while eliminating the problem of temperature dependence and maintaining good workability. it can.

It is a disassembled perspective view which decomposes | disassembles and shows the test body as a model of the said 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.

The highly attenuating composition of the present invention comprises a diene base polymer having no polar group, a liquid copolymer having a butadiene skeleton, and a rosin derivative.
Examples of the diene base polymer having no polar group include one or more of natural rubber, isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SBR), and the like. In particular, natural rubber is preferable because it is easily available and can form a highly attenuating composition at low cost.

  As the liquid copolymer, any of various liquid copolymers having a butadiene skeleton can be used. Among them, a liquid acrylonitrile-butadiene rubber (liquid NBR) which is excellent in an effect of improving damping performance and can function well as a softening agent, At least one selected from the group consisting of liquid isoprene-butadiene rubber (liquid IRBR) and liquid styrene-butadiene rubber (liquid SBR) is preferable.

Examples of the liquid NBR include various NBRs which are copolymers of acrylonitrile and butadiene and exhibit a liquid state at room temperature (3 to 35 ° C.). Examples of the liquid NBR include one or two kinds such as Nipol (registered trademark) 1312 (medium-high nitrile) and DN601 (medium nitrile) manufactured by Nippon Zeon Co., Ltd.
As the liquid IRBR, various IBRs which are copolymers of isoprene and butadiene and also exhibit a liquid state at room temperature (3 to 35 ° C.) can be mentioned. Examples of such a liquid IRBR include Claprene (registered trademark) LIR-390 (molecular weight: 48000, glass transition temperature Tg: -95 ° C.) manufactured by Kuraray Co., Ltd.

  Further, examples of the liquid SBR include various SBRs which are copolymers of styrene and butadiene and which are liquid at room temperature (3 to 35 ° C.). Examples of the liquid SBR include RICON (registered trademark) 100 manufactured by Sartomer (molecular weight: 4500, 1,2 vinyl content: 70%, styrene content: 25%), 181 (molecular weight: 3200, 1,2 vinyl content: 30%, styrene content: 28%), 184 (molecular weight: 8600, 1,2 vinyl content: 30%, styrene content: 28%) and the like.

The content of the liquid copolymer is preferably 10 parts by mass or more, particularly 25 parts by mass or more, and preferably 60 parts by mass or less, particularly 45 parts by mass or less, per 100 parts by mass of the diene base polymer.
When the content ratio is less than the above range, the above-described effect of improving the damping performance of the high damping member and the workability of the high damping composition are improved by functioning as a softening agent by containing the liquid copolymer. The effect may not be obtained sufficiently.

On the other hand, when the content ratio exceeds the above range, the high attenuation composition becomes too soft and the workability is lowered, and it is not easy to knead or form the high attenuation composition into an arbitrary shape. There is a fear.
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. Examples include various derivatives having an effect of improving the damping performance.

The softening point of the rosin derivative is preferably 120 ° C. or higher, preferably 180 ° C. or lower, particularly 160 ° C. or lower.
If the softening point is less than the above range, the effect of improving the damping performance of the high damping member may not be sufficiently obtained. On the other hand, when the above range is exceeded, workability is reduced, each component is kneaded to prepare a high attenuation composition, the high attenuation composition is kneaded to produce a high attenuation member, Alternatively, it may not be easy to mold into an arbitrary shape.

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 the rosin derivative include MSR-4 (softening point: 127 ° C.), DS-130 (softening point: 135 ° C.), AD-130 (trade name) of the Harrier Star series manufactured by Harima Kasei Co., Ltd. Softening point: 135 ° C., DS-816 (softening point: 148 ° C.), DS-822 (softening point: 172 ° C.), 145P (softening point: 138 ° C.) of the product name Harimac series manufactured by Harima Kasei Co., Ltd. ), 135GN (softening point: 139 ° C.), AS-5 (softening point: 165 ° C.) and the like.

  The content of the rosin derivative is preferably 3 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the diene base polymer. When the content ratio is less than 3 parts by mass, there is a possibility that the effect of improving the attenuation performance of the high attenuation member due to the inclusion of the rosin derivative may not be obtained. On the other hand, when the amount exceeds 50 parts by mass, the adhesiveness due to the rosin derivative increases and the processability decreases, and the above components are used to knead each component in order to prepare a high attenuation composition or to manufacture a high attenuation member. There is a possibility that the damping composition cannot be kneaded or molded into an arbitrary shape.

The high attenuation composition of the present invention preferably also contains silica. Since silica functions as an attenuation imparting agent as described above, the attenuation performance of the high attenuation member can be further improved.
As the silica, any of wet process silica and dry process silica classified by the production method may be used.
The silica, considering that to better achieving the good functioning effect of improving the damping performance of the high damping member as damping-imparting agent, the BET specific surface area of 100 m 2 / ^g or more, particularly 200 meters ² / g or more, preferably 400 m ² / g or less, particularly preferably 250 m ² / g or less. The BET specific surface area is represented by a value measured by a gas phase adsorption method using, for example, a rapid surface area measuring device SA-1000 manufactured by Shibata Chemical Machinery Co., Ltd. and using nitrogen gas as an adsorbed gas.

Examples of the silica include Nipsil (registered trademark) KQ manufactured by Tosoh Silica Corporation.
The content ratio of silica is preferably 100 parts by mass or more, particularly 125 parts by mass or more, more preferably 180 parts by mass or less, and particularly preferably 145 parts by mass or less, per 100 parts by mass of the diene base polymer.

If the content ratio is less than the above range, the effect of improving the attenuation performance of the high attenuation member due to the inclusion of the silica as an attenuation imparting agent may not be sufficiently obtained.
If the above range is exceeded, the processability of the high-attenuating composition is lowered as described above, and it is not easy to mass-produce a high-attenuating member having a desired three-dimensional shape, particularly at the factory level. There is. In addition, a small number of high attenuation members can be formed at the laboratory level, but the formed high attenuation members are hard and difficult to deform.

  The highly attenuating composition of the present invention may further contain a silane compound. Since the silane compound functions as a dispersant for improving the compatibility and compatibility of silica with organic components such as diene base polymers and liquid copolymers, the silica is added by adding the silane compound. The damping performance of the high damping member can be further improved by further functioning as a damping property imparting agent in the high damping member.

  Examples of the silane compound include the formula (a):

[Wherein, at least one of R ¹ , R ² , R ³ , and R ⁴ represents an alkoxy group. However, R ¹ , R ² , R ³ , and R ⁴ are not simultaneously an alkoxy group, and represent a cross-linked alkyl group or an aryl group. ]
And various silane compounds that can function as a silica dispersant, such as a silane coupling agent and a silylating agent. In particular, one or more of alkoxysilanes such as hexyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and diphenyldimethoxysilane are preferable.

The content of the silane compound is preferably 10 parts by mass or more and 20 parts by mass or less per 100 parts by mass of silica.
If the content ratio is less than the above range, the effect of improving the damping performance of the high attenuation member by sufficiently allowing silica to function as an attenuation imparting agent in the high attenuation member by including the silane compound is sufficient. May not be obtained.

Moreover, even if the content ratio exceeds the above range, not only the effect is not obtained, but also foaming or the like may occur during vulcanization molding.
The high attenuation composition of the present invention may further contain an attenuating agent other than silica, such as petroleum resin and coumarone resin. What is necessary is just to set the mixture ratio of the said other attenuation | damping property imparting agent suitably according to the attenuation | damping characteristic of a high attenuation | damping member.

Further, the high damping composition of the present invention is blended with an appropriate ratio of additives for vulcanizing the diene base polymer such as a vulcanizing agent, a vulcanization accelerator, a vulcanization accelerating aid and an anti-aging agent. May be.
Furthermore, fillers such as carbon black and calcium carbonate may be blended in the high attenuation composition of the present invention at an appropriate ratio.
The high attenuation composition of the present invention is obtained by kneading the above components using an arbitrary kneading machine, and molding the high attenuation composition into a predetermined three-dimensional shape and vulcanizing it to achieve predetermined attenuation characteristics. A high damping member having

  As the high damping member that can be formed using the high damping composition of the present invention, for example, a seismic isolation damper that is incorporated into the foundation of a building such as a building, and a damping damper that is incorporated into the structure of a building. Damping members for cables such as suspension bridges and cable-stayed bridges, anti-vibration members for industrial machines, aircraft, automobiles, railway vehicles, etc., anti-vibration members for computers and their peripheral devices, household electric appliances, etc. Examples include treads for automobile tires.

According to the present invention, by appropriately adjusting the type and content ratio of the diene base polymer, the liquid copolymer, rosin derivative, silica, silane compound, and other additive types and content ratio with respect to the diene base polymer, A high damping member having excellent damping performance suitable for each application can be obtained.
In particular, when the damping damper incorporated in the structure of a building is formed using the high damping composition of the present invention, the damping damper is excellent in damping performance, so that the damping damper incorporated in one building is used. The quantity of seismic dampers can be reduced. In addition, since the temperature dependency is small, for example, the damping damper can be installed near the outer wall of a building having a large temperature difference.

The preparation and testing of the high attenuation compositions in the following examples and comparative examples were carried out in an environment with a temperature of 20 ± 1 ° C. and a relative humidity of 55 ± 1%, unless otherwise specified.
<Example 1>
Natural rubber [SMR (Standard Malaysian Rubber) -CV60] 100 parts by mass as diene base polymer, liquid IRBR as liquid copolymer [Claprene LIR-390 made by Kuraray Co., Ltd., molecular weight: 48000, glass transition Temperature Tg: -95 ° C 35 parts by mass, rosin derivative [rosin-modified maleic acid resin, softening point: 139 ° C, Harima Chemical Co., Ltd. Harimac 135GN] 10 parts by mass, silica [Tosoh Silica Co., Ltd. ) Nipsil KQ] 135 parts by weight, and phenyltriethoxysilane (KBE-103 made by Shin-Etsu Chemical Co., Ltd.) 23 parts by weight as a silane compound, and the components shown in Table 1 below, and sealed A highly attenuated composition was prepared by kneading using a kneader. The content ratio of phenyltriethoxysilane per 100 parts by mass of silica was 17.0 parts by mass.

Each component in Table 1 is as follows.
Dicyclopentadiene-based petroleum resin: softening point 105 ° C., Marukaretsu (registered trademark) M-890A manufactured by Maruzen Petrochemical Co., Ltd.
Coumarone resin: softening point 90 ° C., Nikko Chemical Co., Ltd. Escron (registered trademark) G-90
Benzimidazole anti-aging agent: 2-mercaptobenzimidazole, NOCRACK MB manufactured by Ouchi Shinsei Chemical Co., Ltd.
Quinone anti-aging agent: Antigen FR manufactured by Maruishi Chemical Co., Ltd.
5% oil-treated powder sulfur: vulcanizing agent, manufactured by Tsurumi Chemical Industry Co., Ltd. Sulfenamide vulcanization accelerator: N-tert-butyl-2-benzothiazolylsulfenamide, manufactured by Ouchi Shinsei Chemical Co., Ltd. Noxeller (registered trademark) NS
Thiuram-based vulcanization accelerator: Noxeller TBT-N manufactured by Ouchi Shinsei Chemical Co., Ltd.
2 types of zinc oxide: Vulcanization accelerating agent, manufactured by Mitsui Mining & Smelting Co., Ltd. Stearic acid: Vulcanization accelerating agent, "Tsubaki" manufactured by NOF Corporation
Carbon Black: Filler, Dia Black (registered trademark) G manufactured by Mitsubishi Chemical Corporation
<Example 2>
A highly attenuated composition was prepared in the same manner as in Example 1 except that the same amount of liquid NBR (NIPOL 1312, medium-high nitrile made by Nippon Zeon Co., Ltd.) was used as the liquid copolymer instead of liquid IRBR. did.

<Example 3>
As the liquid copolymer, the same amount of liquid SBR (RICON 100 manufactured by Sartomer Co., Ltd., molecular weight: 4500, 1,2 vinyl content: 70%, styrene content: 25%) was used instead of liquid IRBR. A highly attenuated composition was prepared in the same manner as in Example 1.
<Comparative example 1>
Implemented except that the same amount of liquid isoprene rubber [Homopolymer, Kuraray LIR-50, Kuraray Co., Ltd., molecular weight: 47000, glass transition temperature Tg: −63 ° C.] was used instead of liquid IRBR as a liquid copolymer. A highly attenuated composition was prepared as in Example 1.

<Comparative example 2>
Instead of using liquid IRBR as a liquid copolymer, the same amount of liquid hydrogenated isoprene rubber [Homopolymer, Kuraray Kuraray LIR-290, molecular weight: 25000, glass transition temperature Tg: −59 ° C.] was used. Prepared a highly attenuated composition in the same manner as in Example 1.
<Comparative Example 3>
Instead of liquid IRBR as a liquid copolymer, the same amount of liquid modified isoprene rubber [Homopolymer, Kuraray Kuraray LIR-403, molecular weight: 25000, glass transition temperature Tg: −60 ° C.] was used. A highly attenuated composition was prepared in the same manner as in Example 1.

<Comparative example 4>
Implemented except that the same amount of liquid butadiene rubber (homopolymer, Kuraray LIR-300 manufactured by Kuraray Co., Ltd., molecular weight: 45000, glass transition temperature Tg: −63 ° C.) was used instead of liquid IRBR as a liquid copolymer. A highly attenuated composition was prepared as in Example 1.
<Comparative Example 5>
Example except that the same amount of liquid styrene-isoprene rubber (Kuraray Kuraray LIR-310, molecular weight: 31000, glass transition temperature Tg: −63 ° C.) was used as the liquid copolymer instead of liquid IRBR. A highly attenuated composition was prepared in the same manner as in 1.

<Comparative Example 6>
In place of liquid IRBR as a liquid copolymer, the same amount of liquid butadiene rubber (homopolymer, RICON 130 manufactured by Sartomer, low vinyl, molecular weight: 2500, 1,2 vinyl content: 28%, vinyl number / chain: 14) is used. A highly attenuating composition was prepared in the same manner as in Example 1 except that.

<Comparative Example 7>
Instead of liquid IRBR as a liquid copolymer, the same amount of liquid butadiene rubber (homopolymer, RICON 134 manufactured by Sartomer, low vinyl, molecular weight: 8000, 1,2 vinyl content: 28%, vinyl number / chain: 41) is used. A highly attenuating composition was prepared in the same manner as in Example 1 except that.

<Comparative Example 8>
In place of liquid IRBR as a liquid copolymer, the same amount of liquid butadiene rubber (homopolymer, RICON 142 manufactured by Sartomer, low vinyl, molecular weight: 3900, 1,2 vinyl content: 55%, vinyl number / chain: 40) A highly attenuating composition was prepared in the same manner as in Example 1 except that.

<Comparative Example 9>
Instead of liquid IRBR as a liquid copolymer, the same amount of liquid butadiene rubber (homopolymer, RICON152 manufactured by Sartomer, high vinyl, molecular weight: 2900, 1,2 vinyl content: 80%, vinyl number / chain: 43) is used. A highly attenuating composition was prepared in the same manner as in Example 1 except that.

<Damping characteristic evaluation>
(Preparation of test specimen)
The high attenuation compositions prepared in Examples and Comparative Examples were extruded into a sheet shape and then punched to produce a disk 1 (thickness 5 mm × diameter 25 mm) as shown in FIG. Further, a highly attenuating composition in which a rectangular plate-shaped steel plate 2 having a thickness of 6 mm, a length of 44 mm, and a width of 44 mm is stacked on each other through a vulcanizing adhesive and heated to 150 ° C. while pressing in the laminating direction to form the disk 1 , 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 specimens 3 are prepared, and the two test specimens 3 are fixed to one central fixing jig 4 via one steel plate 2, respectively. One left and right fixing jig 5 was fixed to the other steel plate 2 of the test body 3. Then, the central fixing jig 4 is fixed to a fixing arm 6 arranged on the upper side of the testing machine via a joint 7, and two left and right fixing jigs 5 are arranged on the lower side of the testing machine. The movable platen 8 was fixed via a joint 9. A bolt (not shown) was used for each fixation.

  Next, from the above state (initial 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 moved to the position shown in FIG. As shown in (b), a deformed state in which the specimen 3 is strained and deformed in a direction orthogonal to the stacking direction is obtained, and then from this deformed state, the movable platen 8 is fixed arm 6 as indicated by a white arrow in the figure. The disc 1 was repeatedly deformed, that is, oscillated by repeating the operation for 3 cycles by displacing it so as to be pulled down in the direction opposite to the direction and returning it to the initial state shown in FIG.

The hysteresis loop shown in FIG. 3 shows the relationship between the displacement (mm) and the load (N) of the disc 1 in the direction orthogonal to the stacking direction of the test body 3 when the strain deformation of the third cycle is performed. Asked.
The maximum amount of displacement was set such that the amount of deviation of the two steel plates 2 sandwiching the disc 1 in the direction perpendicular to the stacking direction was 100% of the thickness of the disc 1.

Next, 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 of FIG. 3 obtained by the measurement is obtained, and the straight line L ₁ and the hysteresis loop H grated perpendicular L ₂ from the intersection on the horizontal axis of the graph.
Then, the absorbed energy amount ΔW represented by the total surface area of the hysteresis loop H shown with diagonal lines in FIG. 3 and the straight line L ₁ and the perpendicular line L ₂ shown with halftone lines in FIG. And the elastic strain energy W expressed by the surface area of the right-angled triangular region surrounded by the horizontal axis of the graph, the formula (1):

Thus, an equivalent damping constant Heq was obtained.
It can be determined that the greater the equivalent attenuation constant Heq, the better the specimen 3 is in attenuation performance. In this example and comparative example, the value of the equivalent damping constant Heq itself is compared, and the equivalent damping constant Heq relative to the equivalent damping constant Heq of Comparative Example 1 using conventional liquid isoprene rubber as a softening agent is compared. The rate of change (%) was determined, and those with the rate of change of + 5% or more were determined to be excellent in attenuation performance. The results are shown in Tables 2 and 3. In addition, since the test body 3 formed using the high attenuation composition of Comparative Examples 3 and 4 could not be deformed by ± 100%, the equivalent attenuation constant Heq could not be obtained.

  When Examples 1 to 3 and Comparative Examples 1 to 9 in Table 2 and Table 3 are compared, a liquid copolymer having a butadiene skeleton is used as a softening agent, and a high attenuation composition of Examples 1 to 3 to which a rosin derivative is added is used. Thus, it was found that a high attenuation member having excellent attenuation characteristics as compared with the conventional case can be formed.

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 (6)

  A high-damping composition comprising a diene base polymer having no polar group, a liquid copolymer having a butadiene skeleton, and a rosin derivative.   2. The high attenuation composition according to claim 1, wherein the liquid copolymer is at least one selected from the group consisting of liquid acrylonitrile-butadiene rubber, liquid isoprene-butadiene rubber, and liquid styrene-butadiene rubber.   The high-damping composition according to claim 1 or 2, wherein the diene base polymer is natural rubber.   The high attenuation composition according to any one of claims 1 to 3, further comprising 100 parts by mass or more and 180 parts by mass or less of silica per 100 parts by mass of the diene base polymer.   The high attenuation | damping composition of Claim 4 which also contains 10 mass parts or more and 20 mass parts or less of silane compounds per 100 mass parts of said silica.   The high-damping composition according to any one of claims 1 to 5, which is used as a material for forming a damping damper for a building.

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