JP2006143849A - Rubber composition for high damping laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber composition for a high damping laminate giving a laminate having high damping coefficient, excellent shear modulus, stable damping coefficient and shear modulus to a long-term repeated shear deformation and small temperature dependence of damping coefficient and shear modulus. <P>SOLUTION: The rubber composition for a high damping laminate contains 100 pts.mass of a diene rubber, 40-75 pts.mass of carbon black, 5-35 pts.mass of silica, 5-55 pts.mass of an inorganic filler and 5-50 pts.mass of a petroleum resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rubber composition for a high attenuation laminate.

  In recent years, seismic energy absorbing devices, that is, seismic isolation devices, seismic isolation devices, seismic isolation devices, and the like are rapidly spreading. For example, seismic isolation rubber is used for bridge support and base isolation of buildings. The seismic isolation laminated rubber is a laminated body in which a rubber composition and a hard plate are usually laminated and bonded alternately in a few layers to a dozen layers. Such seismic isolation laminated rubber has a hardness that can support a building in the vertical direction and a softness that gives a gentle reciprocating motion to the building during an earthquake in the horizontal direction. That is, the seismic isolation laminated rubber reduces shear rigidity and acts so as to shift the natural vibration period of the building from the vibration period of the earthquake, thereby greatly reducing the acceleration that the building receives from the earthquake. The characteristics required for the above-mentioned seismic isolation laminated rubber include, for example, high damping properties (attenuating vibration energy by converting vibration into more heat) and a desired shear modulus. Can be mentioned.

Examples of the rubber composition used for the seismic isolation laminated rubber include those described in Patent Documents 1 to 4.
The rubber composition for a seismic isolation laminate described in Patent Document 1 is a block copolymer in which the glass transition temperature of polystyrene and vinyl-polyisoprene is −15 ° C. or more with respect to 100 parts by mass of rubber mainly composed of natural rubber. A rubber composition for a base-isolated laminate comprising 5 to 30 parts by mass of a polymer, 15 to 60 parts by mass of a petroleum resin, and 50 to 90 parts by mass of fine carbon black. The rubber composition for a seismic isolation laminate is described as being excellent in vibration energy absorption and long-term durability.
The high-damping rubber composition described in Patent Document 2 includes 15 to 60 parts by mass of petroleum resin, fine particle carbon black, and 100 parts by mass of rubber containing 50 parts by mass or more of natural rubber and / or isoprene rubber. The high-damping rubber composition is characterized in that it contains 60 to 95 parts by mass of silica in total, and a mass part ratio of the fine particle carbon black to the silica is in a range of 95/5 to 75/25. It is described that the high damping rubber composition has a low elastic modulus and is excellent in damping performance, fracture characteristics and the like.
The rubber composition for high damping bearing described in Patent Document 3 has 60 to 100 parts by mass of carbon black having a CTAB adsorption specific surface area of 120 m ² / g or more with respect to 100 parts by mass of the rubber component, and a reinforcing effect. It is a rubber composition for high damping bearings characterized by containing 10 parts by mass or more of an inorganic filler with a low content. It is described that the rubber composition for high damping bearings has a high damping rate and a low strain dependency between the damping rate and the shear modulus.
Seismic isolation laminate-body rubber composition described in Patent Document 4, 1) diene rubber, 2) with a CTAB specific surface area of 120~220m ² / g, CTAB specific surface area (m ² / g) / so The diene rubber comprising carbon black having an elemental adsorption amount (mg / g) of 0.90 or less, and 3) a terpene resin and / or an alicyclic saturated hydrocarbon resin having a softening point of 70 to 150 ° C. For the seismic isolation laminate, the content of the carbon black is 40 to 160 parts by mass and the content of the terpene resin and / or alicyclic saturated hydrocarbon resin is 1 to 60 parts by mass with respect to 100 parts by mass. It is a rubber composition. It is described that the rubber composition for a seismic isolation laminate has excellent mechanical properties and damping rate, and the temperature dependence of shear modulus is small and has stable shear elasticity throughout the year.

Japanese Patent Laid-Open No. 10-110063 International Publication No. 98/16580 Pamphlet JP 2002-20546 A Japanese Patent Laid-Open No. 2004-27080

In the recent seismic isolation laminated rubber, in addition to (1) high damping, (2) excellent shear modulus, (3) even if the seismic isolation laminated rubber is repeatedly shear-deformed over a long period of time, It is required that the damping property and the shear modulus are stable, and (4) that the temperature dependency of the damping property and the shear modulus is small throughout the year. The above (3) is a characteristic that has not been required in the past, and the rubber composition for a laminated rubber for seismic isolation that has been developed so far has all the other required characteristics as well as the new required characteristic (3). I couldn't be satisfied.
Therefore, the present invention realizes a laminate having a high damping property, an excellent shear modulus, a stable damping property and shear modulus for a long-term repeated shear deformation, and a small temperature dependency of the damping property and the shear modulus. An object of the present invention is to provide a rubber composition for a high attenuation laminate.

As a result of diligent studies to achieve the above-mentioned problems, the present inventor used a rubber composition in which a diene rubber, carbon black, silica, an inorganic filler, and a petroleum resin were blended at a specific ratio. It was discovered that a laminate with high damping property, excellent shear modulus, stable damping property and shear modulus for long-term repeated shear deformation, and low temperature dependence of damping property and shear modulus can be obtained. The invention has been completed.
The above object is achieved by the present inventions (1) to (3) shown below.

(1) High containing 100 parts by mass of diene rubber, 40 to 75 parts by mass of carbon black, 5 to 35 parts by mass of silica, 5 to 55 parts by mass of an inorganic filler, and 5 to 50 parts by mass of petroleum resin. Rubber composition for damping laminate.

(2) The total amount of the silica and the inorganic filler is 20 to 75 parts by mass with respect to 100 parts by mass of the diene rubber,
The rubber composition for a high attenuation laminate according to the above (1), wherein the mass ratio of the silica and the inorganic filler is 1/1 to 1 / 2.5.

(3) The rubber composition for a high attenuation laminate according to the above (1) or (2), wherein the mass ratio of the inorganic filler to the petroleum resin is 1 / 0.2 to 1 / 3.5.

  The rubber composition for a high-damping laminate of the present invention has a high damping property and excellent shear modulus when formed into a laminate, and has a stable damping property and shear modulus for long-term repeated shear deformation. The temperature dependence of the shear modulus is small.

The present invention is described in detail below.
The rubber composition for highly attenuated laminates of the present invention comprises 100 parts by weight of a diene rubber, 40 to 75 parts by weight of carbon black, 5 to 35 parts by weight of silica, 5 to 55 parts by weight of an inorganic filler, and petroleum resin. It is a rubber composition for high attenuation laminated bodies containing 5-50 mass parts.

  The diene rubber used in the present invention is not particularly limited. For example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber (NBR), butyl rubber (IIR), halogenated butyl rubber ( Br-IIR, Cl-IIR), chloroprene rubber (CR) and the like.

Among these, NR is preferable from the viewpoint of a good balance between attenuation and workability, and BR is preferable from the viewpoint of reducing the temperature dependence of the attenuation and shear modulus.
The average molecular weight, monomer composition molar ratio, halogenation rate, and the like of these diene rubbers are not particularly limited, and can be arbitrarily set depending on the intended use.

  In the rubber composition for highly attenuated laminates of the present invention, the above diene rubbers can be used alone or in combination of two or more. As a suitable combination of the above-mentioned diene rubbers when two or more kinds are used in combination, the rubber components are excellent in compatibility, processability, green strength and vulcanized physical properties, and the temperature dependence and damping of the high damping laminate. From the viewpoint of securing the property, for example, NR and BR, IR and BR, NR, IR and BR can be mentioned. Among these, NR and BR are preferable because they are more excellent in this characteristic. These mixing ratios are not particularly limited.

  The rubber composition for a high attenuation laminate of the present invention contains carbon black. When carbon black is contained, a high shear modulus of the high damping laminate can be secured, and a high damping property can be secured.

A conventionally well-known carbon black can be used for this invention. Among them, CTAB adsorption specific surface area of 100 m ² / g or more, preferably carbon black 110~370m ² / g. The CTAB adsorption specific surface area is a value measured by adsorption of CTAB (cetyltrimethylammonium bromide) on the surface area that carbon black can use for adsorption with rubber molecules.

  When the CTAB adsorption specific surface area is in the above range, it is possible to maintain a high attenuation of the laminate using the obtained rubber composition. Examples of such carbon black include SAF, ISAF, and HAF. The CATB adsorption specific surface area can be measured by the method described in ASTM D3765-80.

  The amount of carbon black is 40 to 75 parts by mass and preferably 50 to 75 parts by mass with respect to 100 parts by mass of the diene rubber. When the amount of carbon black is within such a range, the strength of the high-damping laminate can be ensured, and excellent shear modulus and high damping can be secured. Damping and shear modulus against long-term repeated shear deformation Is stable.

The rubber composition for highly attenuated laminates of the present invention contains silica.
A conventionally well-known thing can be used for the silica used for this invention. Examples thereof include fumed silica, calcined silica, precipitated silica, pulverized silica, and fused silica.
Silica preferably has an average aggregate particle diameter of 5 to 50 μm, more preferably 5 to 30 μm.

  The quantity of a silica is 5-35 mass parts with respect to 100 mass parts of diene rubbers, Preferably it is 10-30 mass parts. In such a range, the damping property and the shear modulus are excellent.

The rubber composition for highly attenuated laminates of the present invention contains an inorganic filler.
In the present invention, the inorganic filler does not include carbon black and silica.
Examples of the inorganic filler used include soft clay such as T-clay, kaolin clay, wax stone clay, sericite clay, and calcined clay; diatomaceous earth; heavy calcium carbonate, magnesium carbonate, aluminum hydroxide, Examples include aggregates of barium sulfate, talc, quartz and kaolinite. Among these, T-clay, kaolin clay, and an aggregate of quartz and kaolinite are preferable from the viewpoint that damping property and stability against long-term shear deformation can be kept particularly high.

A conventionally well-known thing can be used for the aggregate of said quartz and kaolinite. Especially, it is preferable that it is a natural coupling | bonding material of block quartz and plate-shaped kaolinite. Specifically, as a commercially available product, for example, siritin (Siritin Z86, Siritin V85, Siritin N82, Siritin 85, Siritin N87 (all manufactured by Hoffman Mineral Co., Ltd.)) is preferable. In addition, what has the same structure manufactured artificially can also be used.
In the case of containing an aggregate of quartz and kaolinite, the rubber composition for a high-damping laminate is particularly excellent in the effect of improving the stability of damping and shear modulus described later, and when used in combination with a petroleum resin described later. In addition, the damping and shear modulus can be stably exhibited.

  The mass ratio (quartz / kaolinite) of quartz and kaolinite constituting the aggregate of quartz and kaolinite is not particularly limited. From the viewpoint of stably exhibiting higher damping properties and higher shear modulus even when a laminate using the rubber composition containing the aggregate is repeatedly subjected to shear deformation, the mass ratio of quartz and kaolinite Is preferably 12/1 to 1/1, and more preferably 9/1 to 2/1 from the viewpoint of better properties.

  The aggregate of quartz and kaolinite can contain, for example, iron oxide, phosphorus component, and sulfur component in addition to quartz and kaolinite. Such aggregates can be used alone or in combination of two or more.

  The amount of the inorganic filler is 5 to 55 parts by mass, preferably 10 to 50 parts by mass, and more preferably 15 to 40 parts by mass with respect to 100 parts by mass of the rubber component. When the amount of the inorganic filler is within such a range, the obtained laminate can have a stable damping property and shear modulus against a long-term repeated shear deformation while maintaining a high damping property.

  Moreover, it is preferable that it is 20-75 mass parts with respect to 100 mass parts of said diene rubbers, and, as for the total amount of a silica and an inorganic filler, 30-65 mass parts is more preferable. When the total amount of silica and inorganic filler is in such a range, the damping is higher, the damping against long-term repeated shear deformation and the shear modulus are more stable, and the balance is high. A rubber composition for a damping laminate is obtained.

  The mass ratio of silica and inorganic filler is preferably 1/1 to 1 / 2.5, more preferably 1/1 to 1 / 2.0. When the mass ratio of silica and inorganic filler is within this range, good processability can be obtained.

The rubber composition for a highly attenuated laminate of the present invention contains a petroleum resin.
Examples of the petroleum resin used include C5 aliphatic unsaturated hydrocarbon polymers, C9 aromatic unsaturated hydrocarbon polymers, C5 aliphatic unsaturated hydrocarbons and C9 aromatics. And a copolymer with a group unsaturated hydrocarbon.
The rubber composition for a high damping laminate containing the above-mentioned petroleum resin is particularly excellent in the damping improvement effect, and when used in combination with the agglomerates of quartz and kaolinite described above, high damping and excellent shear modulus are stable. Can be demonstrated.

Examples of the C5 aliphatic unsaturated hydrocarbon include 1-pentene, 2-pentene, 2-methyl-1-butene, and 3-methyl-1 contained in a C5 fraction obtained by thermal decomposition of naphtha. Olefinic hydrocarbons such as butene and 2-methyl-2-butene; of 2-methyl-1,3-butadiene, 1,2-pentadiene, 1,3-pentadiene, 3-methyl-1,2-butadiene Such diolefin hydrocarbons can be mentioned.
These can be polymerized or copolymerized in the presence of a suitable catalyst. Here, the C5 aliphatic unsaturated hydrocarbon polymer is a co-polymer of a single C5 aliphatic unsaturated hydrocarbon homopolymer and two or more C5 aliphatic unsaturated hydrocarbons. It refers to any polymer.

Examples of the C9 aromatic unsaturated hydrocarbon include α-methylstyrene, o-vinyltoluene, m-vinyltoluene, and p-vinyltoluene contained in the C9 fraction obtained by thermal decomposition of naphtha. And vinyl-substituted aromatic hydrocarbons.
These can be polymerized or copolymerized in the presence of a suitable catalyst. Here, the C9 aromatic unsaturated hydrocarbon polymer is a co-polymer of a single C9 aromatic unsaturated hydrocarbon homopolymer and two or more C9 aromatic unsaturated hydrocarbons. It refers to any polymer.

In addition, a copolymer of a C5 aliphatic unsaturated hydrocarbon and a C9 aromatic unsaturated hydrocarbon is a C9 aromatic unsaturated hydrocarbon in that the softening point of the copolymer is high. What a unit is 60 mol% or more is preferable, and what is 90 mol% or more is more preferable.
A copolymer of a C5 aliphatic unsaturated hydrocarbon and a C9 aromatic unsaturated hydrocarbon can be copolymerized in the presence of a suitable catalyst.

  The above-mentioned petroleum resin has a molecular weight and a double bond reactivity affecting the physical properties of the diene rubber, so that the softening point (JIS K2207) is preferably 100 ° C. or higher, more preferably 120 ° C. or higher. preferable.

  The amount of the petroleum resin is 5 to 55 parts by mass and preferably 10 to 45 parts by mass with respect to 100 parts by mass of the diene rubber. When the amount of the petroleum resin is within this range, the laminate using the rubber composition maintains a high damping property, has a low temperature dependency, and does not deteriorate the stability against long-term repeated shear deformation. Excellent characteristics can be obtained.

  The mass ratio of the inorganic filler to the petroleum resin (inorganic filler / petroleum resin) is preferably 1 / 0.2 to 1 / 3.5 in the range of parts by mass. In such a range, it is excellent in high damping property and stability against repeated shear deformation. From the viewpoint of being superior in the properties, it is more preferably 1/1 to 1 / 3.0, and particularly preferably 1/1 to 1 / 2.5.

  The rubber composition for highly attenuated laminates of the present invention comprises other additives such as vulcanizing agents such as sulfur and zinc oxide; organic sulfur-containing compounds such as TMTD, and organic peroxides such as dicumyl peroxide. Etc .; sulfenamides such as N-cyclohexyl-2-benzothiazole sulfenamide (CBS), thiazoles such as mercaptobenzothiazole, thiuram such as tetramethylthiuram monosulfide, vulcanization such as stearic acid, etc. Accelerators: Ketone / amine condensates such as TMDQ, amines such as DNPD, monophenols such as styrenated phenol, etc .; phthalic acid derivatives such as DBP and DOP, sebacins such as DBS Plasticizers such as monoesters such as acid derivatives; paraffinic oils (process oils, etc.) It can contain heat stabilizers; agents; vulcanizing aid; flame retardants; weathering agents.

  The rubber composition for a highly attenuated laminate of the present invention can be prepared by kneading, etc., using a known method and apparatus by appropriately shaping an unvulcanized rubber composition containing the above-described components.

  Examples of the laminate in which the rubber composition for a high attenuation laminate of the present invention is used (hereinafter sometimes referred to as “high attenuation laminate”) include the rubber composition for a high attenuation laminate of the present invention and a hard The thing obtained by laminating | stacking a board alternately can be mentioned.

  Such a high-attenuation laminate is obtained by molding and vulcanizing the rubber composition for a high-attenuation laminate of the present invention to obtain a sheet-like rubber composition, and then providing a layer containing an adhesive to provide a hard It can also be manufactured by alternately laminating with a plate, or a rubber composition for a highly damped laminated body of the present invention that has not been vulcanized in advance is formed into a sheet shape, alternately laminated with a hard plate, and then heated. It can also be manufactured by performing vulcanization and adhesion at the same time. As the hard plate, for example, a metal plate such as a steel plate is used.

  The high damping laminate using the rubber composition for a high damping laminate of the present invention has high damping properties, excellent shear modulus, stable damping property against repeated shear deformation over a long period of time, and stable shear modulus. The temperature dependence of the shear modulus is small.

  Therefore, in the high attenuation laminate, the equivalent attenuation constant (Heq) and shear modulus (Geq) required for each product are satisfied, and the Heq change ratio and Geq change ratio in the high attenuation laminate of the present invention described later are described. The temperature dependency is preferably in the following range.

  The lower limit of the Heq change ratio in the highly attenuated laminate is preferably 0.81 or more from the viewpoint of small decrease in Heq against repeated shear deformation (small decrease in attenuation). 0.83 or more is more preferable, and 0.85 or more is particularly preferable. How to obtain the Heq and the Heq change ratio will be described later.

In addition, the upper limit of the Geq change ratio in the highly attenuated laminate is preferably 1.07 or less from the viewpoint that the increase in Geq is small (the increase in shear rigidity is small), and 1.06 or less is superior in terms of these. More preferred is 1.05 or less. Further, the lower limit of the Geq change ratio is preferably 0.93 or more from the viewpoint that the decrease in Geq is small, and 0.94 or more is more preferable, and 0.95 or more is particularly preferable in terms of being superior to these. A method for obtaining the Geq and the Geq change ratio will be described later.
The temperature dependence of Geq in the highly attenuated laminate is such that the ratio of Geq (Geq- ^{10 ° C} ) measured at -10 ° ^C to Geq (Geq23 ^{° C} ) measured at room temperature (23 ° C) is 1.00-1. 40 is preferable, and 1.00 to 1.30 is more preferable.
The temperature dependence of Heq in the highly attenuated laminate is such that the ratio of Heq (Heq ^{−10 ° C.} ) measured at −10 ° ^C. to Heq (Heq ^{23 ° C.} ) measured at room temperature (23 ° C.) is 1.00-1. 30 is preferable, and 1.00 to 1.20 is more preferable.

The Heq and Geq of the high damping laminate is measured by a lap shear test.
FIG. 1 is a schematic side view of a sample for a lap shear type shear test. In FIG. 1, 1 is a sample for a lap shear type shear test, 2 is an unvulcanized rubber composition, and 3 is a steel plate.
The unvulcanized rubber composition 2 is an unvulcanized rubber composition of the rubber composition for high damping lamination of the present invention, which has been rolled to a size of 25 mm width × 25 mm length × 5 mm thickness. The steel plate 3 is a steel plate (width 25 mm × length 100 mm × thickness 20 mm) having a surface sandblasted and coated with a metal adhesive.
A sample 1 for a lap shear type shear test is obtained by placing (stacking) an unvulcanized rubber composition 2 and a steel plate 3 as shown in FIG. 1 and then press vulcanizing at 130 ° C. for 120 minutes. .

The lap shear shear test is performed under the following conditions using a vibrator (manufactured by Saginomiya), an input signal oscillator, and an output signal processor.
Using the sample for a lap shear type shear test produced as described above, a deformation frequency of 0.5 Hz by a biaxial shear tester, a measurement temperature of 23 ° C., and each time when 175% strain was applied 10 times. An average (n = 10) of shear characteristic values (Geq ¹ , Heq ¹ ) is obtained. Geq ¹ and Heq ¹ are calculated according to the following formulas (1) and (2) from the hysteresis loop obtained by the lap shear type shear test. FIG. 2 shows an example of a hysteresis loop obtained by a lap shear type shear test.
In addition, using this high attenuation laminate, after adding 70% strain 5000 times under the same conditions, average shear property values (Geq ² , Heq ² ) are obtained under the same conditions as the above shear property values.

From the Geq ¹ , Heq ¹ , Geq ² , and Heq ² thus determined, the Geq change ratio and the Geq change ratio can be obtained. That is, the Heq change ratio is a value obtained by dividing Heq ² by Heq ¹ . Further, the Geq change ratio is a value obtained by dividing Geq ² by Geq ¹ . With this Heq change ratio and Geq change ratio, it is possible to evaluate changes in physical properties when the laminate is repeatedly subjected to shear deformation for a long period of time.

  The equivalent damping constant (Heq) and shear modulus (Geq) of the high damping laminate are expressed by the following formulas (1) and (2), respectively.

In equation (1), ΔW is the area of the hysteresis loop (the shaded area in FIG. 2).
In the formula (2), Keq is represented by the following formula (3), H represents the total thickness of the rubber layer laminated in the high attenuation laminate, and A is the cross-sectional area of the rubber layer.

  The use, application conditions, and the like of the high attenuation laminate are not particularly limited as long as the high attenuation laminate is used as a vibration energy absorber. Among these, since it has the above-described excellent characteristics, it is preferably used as a vibration energy absorption device for buildings. For example, various vibration energy absorption devices for vibration isolation, vibration isolation, vibration isolation, etc. Is suitably used for, for example, support of road bridges, bridges, building base isolation, and detached base isolation applications).

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely according to an Example, this invention is not limited to the following Example.

Examples 1-7, Comparative Examples 1-5 (Preparation of a sample for a lap shear type shear test)
First, an unvulcanized rubber composition prepared by blending each compound with the composition shown in Table 1 below (unit: part by mass) and kneading for 5 minutes with a B-type Banbury mixer was 25 mm wide × long. Rolled to a size of 25 mm in thickness and 5 mm in thickness. The unvulcanized rubber composition (2 in FIG. 1) and a steel plate (width 25 mm × length 100 mm × thickness 20 mm, 3 in FIG. 1) coated with a metal adhesive by sandblasting the surface, 1 was placed (laminated) as shown in the side view of the lap shear type shear test sample 1 and then press vulcanized at 130 ° C. for 120 minutes to prepare a lap shear type shear test sample.

1. Lap shear test The lap shear test was performed using a vibrator (manufactured by Saginomiya), an input signal oscillator, and an output signal processor. As the sample, the above lap shear type shear test sample was used (the number of samples used in each example was 10). The sample was subjected to a lap shear shear test by applying 175% strain 10 times at a deformation frequency of 0.5 Hz with a biaxial shear tester at a measurement temperature of 23 ° C. Using Xmax and Qmax indicated by the hysteresis loop obtained by the lap shear shear test, average shear characteristic values (Geq ¹ , Heq ¹ ) were determined according to the formulas (1) and (2). Subsequently, using the sample, a lap shear shear test was performed again with a shear tester similar to the above, with a deformation frequency of 0.5 Hz, a measurement temperature of 23 ° C., and 70% strain applied 5000 times. The average shear property values (Geq ² , Heq ² ) were determined in the same manner as the above average shear property values (Geq ¹ , Heq ¹ ). The results are shown in Table 1.

2. Calculation and Evaluation Results of Geq Change Ratio and Heq Change Ratio Geq ² was divided by Geq ¹ to obtain a Geq change ratio. Further, Heq ² was divided by Heq ¹ to obtain a Heq change ratio.
As an evaluation result of the Geq change ratio, the case where the value of Geq ² / Geq ¹ is 0.95 or more and less than 1.04 is ◯, 1.04 or more and less than 1.05 is Δ, and 1.05 or more is used. X.
As the evaluation result of the Heq change ratio, the value of Heq ² / Heq ¹ is x when it is less than 0.80, Δ when it is 0.80 or more and less than 0.81, and when it is 0.81 or more and 1.00 or less. ○.
The results are shown in Table 1.

3. Evaluation of temperature dependence Using the lap shear type shear test sample prepared as described above, a deformation frequency of 0.5 Hz by a biaxial shear tester, a measurement temperature of room temperature (23 ° C.), and a 175% strain of 10 The average (n = 10) (Geq ^{23 ° C.} , Heq ^{23 ° C.} ) of the shear characteristic values at room temperature for each time of addition was determined. Next, in the same manner as when the measurement temperature was room temperature (23 ° C.) except that the measurement temperature was changed to −10 ° C., the average shear property value at −10 ° C. (n = 10) (Geq ^{−10 ° C.} , Heq ^{−10 ° C.} ). Then, Geq ^{−10 °} C./Geq ^{23 ° C.} (described as “ ^{−10 °} C./room temperature” in Table 1) was calculated as the Geq temperature dependency. In addition, as an evaluation result of Geq temperature dependency, a value of Geq ^{−10 °} C./Geq ^{23 ° C.} is ◯ when the value is 1.00 or more and 1.30 or less, and Δ or more when it is larger than 1.30 and 1.40 or less. The case where it was larger than 1.40 was set as x. The Heq temperature dependence was similarly performed. The results are shown in Table 1.

Ingredients in Table 1 Natural rubber: TSR20
Butadiene rubber: Nipol BR1220, manufactured by Nippon Zeon Co., Ltd. Carbon black: Diamond Black I, manufactured by Mitsubishi Chemical Corporation Petroleum resin: High Resin # 120 (softening point 120 ° C, manufactured by Toho Chemical Co., Ltd.)
Soft clay: Union Clay RC-1, manufactured by Takehara Chemical Industry Co., Ltd. Siritin: Siritin Z86 (mass ratio (quartz: kaolinite) approximately 6.8: 1, density 2.6 g / cm ³ ), aluminum hydroxide manufactured by Hoffman Mineral Co., Ltd. : Heidilite H-42M, SHEPHERD CHEMICAL CO. Talc: MISTON VAPOR, manufactured by Nippon Mystron, Inc. Barium sulfate: precipitated barium sulfate 100, manufactured by Sakai Chemical Industry Co., Ltd. Silica: Nipseal VN3, manufactured by Tosoh Silica Co., Ltd. Powdered sulfur, manufactured by Hosoi Chemical Industry Co., Ltd. Vulcanization accelerator: Noxeller CZ, manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

As is clear from Table 1, any of the laminates obtained from the rubber compositions for high-attenuation laminates of Examples 1 to 7 has (1) a high damping property and (2) an excellent shear modulus. (3) Damping property and shear modulus for long-term repeated shear deformation were stable, and (4) Temperature dependence of damping property and shear modulus was small. As described above, the rubber compositions for high-attenuation laminates of Examples 1 to 7 were able to have the above four characteristics due to a specific balance of blending.
The laminates obtained from the rubber compositions for high attenuation laminates of Comparative Examples 1 to 5 could not satisfy the characteristics (3) and / or (4).

FIG. 1 is a schematic side view of a sample for a lap shear type shear test. FIG. 2 is a graph showing an example of the hysteresis curve of the laminate.

Explanation of symbols

1 Sample for lap shear type shear test 2 Unvulcanized rubber composition 3 Steel plate

Claims (3)

  High attenuation laminate comprising 100 parts by weight of a diene rubber, 40 to 75 parts by weight of carbon black, 5 to 35 parts by weight of silica, 5 to 55 parts by weight of an inorganic filler, and 5 to 50 parts by weight of a petroleum resin. Rubber composition. The total amount of the silica and the inorganic filler is 20 to 75 parts by mass with respect to 100 parts by mass of the diene rubber,
The rubber composition for a high attenuation laminate according to claim 1, wherein a mass ratio of the silica and the inorganic filler is 1/1 to 1 / 2.5. The rubber composition for a high attenuation laminate according to claim 1 or 2, wherein a mass ratio of the inorganic filler to the petroleum resin is 1 / 0.2 to 1 / 3.5.

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