JP2002161209A - Vibration-damping material composition and vibration damper comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a vibration-damping material composition having an excellent balance between damping properties in the vicinity of room temperature and temperature dependence of rigidity, and to obtain a vibration damper using the same. SOLUTION: This vibration-damping material composition comprises a mixed composition of (a) a block copolymer composed of a polymer block consisting essentially of isobutylene and a polymer block consisting essentially of an aromatic vinyl-based compound and (b) asphalt in a specific range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping composition for a vibration damper (viscoelastic damper) which absorbs shock and displacement of a skeletal structure forming material in the construction field.

[0002]

2. Description of the Related Art In the field of construction, a vibration damper for absorbing a shaking caused by an earthquake, a typhoon, or the like and giving a very high vibration damping structure to a building is being developed. For damping materials used for vibration dampers with stable damping properties, high damping properties are required in order to exhibit the effect of absorbing shocking displacement and vibration of the skeletal structure forming material. In addition, it is required that the rigidity around the room temperature has small temperature dependence in consideration of environmental conditions.

[0003] A normal rubber material has a certain degree of damping property at around room temperature. However, if the damping property is further increased, the rigidity is reduced and it is difficult to reduce the size of the vibration damper. Problems arise. It is also difficult to obtain a high damping property that can be used for a vibration damper.

On the other hand, damping rubber generally has a glass transition temperature (Tg) near room temperature. Examples of such a commercially available oil-loaded norbornene rubber, a styrene-isoprene-based block copolymer having a high vinyl content, and a hydrogenated product thereof (trade name: Hybler) are commercially available.
Such a material has a high damping property near room temperature,
Since the change in elastic modulus is large near g, the temperature dependence of the rigidity near room temperature is very large, and it is difficult to use it in a vibration damper.

As a vibration damping material for a vibration damper in the field of construction, polyurethane compounds and polyurethane / asphalt compositions (JP-A-10-33045)
No. 1) is disclosed. However, all of the materials are required to be further improved with respect to the balance between the damping property near room temperature and the temperature dependence of rigidity. In particular,
In order to reduce the temperature dependence of the rigidity near room temperature, the composition has a Tg of 0 ° C. or less, and thus low attenuation around 20 to 40 ° C. poses a problem.

On the other hand, the fact that a damping material can be obtained from a styrene-isobutylene-based block copolymer is disclosed in WO93 / 1.
No. 4135 and Japanese Unexamined Patent Publication No. Hei 7-137194, each of which only discloses that it can be used as a general vibration damping material. Nothing is described for use in applications where special properties are required. Further, the materials disclosed in the examples of both publications have too low attenuating property at around room temperature, and are difficult to use as damping materials for damping dampers.

Further, Japanese Patent Application Laid-Open No. 5-9389 describes a composition comprising a styrene-isobutylene-based block copolymer and asphalt. However, an asphalt composition excellent in heat deterioration resistance and flexibility at low temperatures is provided. It only discloses that it can be used as a material, but does not describe anything about its use in damping material applications.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive vibration damping material which is excellent in balance between the contradictory characteristics of damping properties near room temperature and the temperature dependence of rigidity, and which is inexpensive. It is to provide a vibration damper.

[0009]

That is, the vibration damping composition of the present invention comprises (a) a block copolymer comprising a polymer block mainly composed of isobutylene and a polymer block mainly composed of an aromatic vinyl compound; The polymer is composed of (b) asphalt and (a) :( b) in a weight ratio of 5:95 to 90:
It is preferable to use a damping material composition having a weight ratio of (a) :( b) of 10:90 to 80:20.
Further, (a) :( b) is 40:60 to 60: 4 in weight ratio.
More preferably, it is 0.

From the viewpoint of vibration damping properties, a composition further containing at least one selected from a plasticizer and a tackifying resin is preferable, and the storage modulus (G ′) obtained by dynamic viscoelasticity measurement in shear mode. ) At 10 ° C. and 30 ° C. (G ′ ₁₀ ° C./G ′ ₃₀ ° C.) is 7 or less, and the loss tangent (tan δ) obtained in the above-mentioned measurement is 10 ° C. to 30 ° C.
Those at 0.4 ° C. or more are particularly preferred. On the other hand, a vibration damper of the present invention is a vibration damper using the above-described vibration damping material composition.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The vibration damping composition of the present invention comprises (a) a block copolymer composed of a polymer block mainly composed of isobutylene and a polymer block mainly composed of an aromatic vinyl compound, and (b) a composition composed of asphalt. The object is used as a vibration damping material.

(A) Isobutylene which can be used in the present invention
The aromatic vinyl block copolymer is not particularly limited as long as it is a block copolymer composed of a polymer block containing isobutylene as a main component and a polymer block containing an aromatic vinyl compound as a main component. Any of block copolymers, diblock copolymers, triblock copolymers, multiblock copolymers, and the like having a chain, branched, or star-like structure can be selected. What is necessary is just to select a material that meets the physical properties such as the strain rate and the shear strength and the workability. By using a composition comprising (a) an isobutylene-aromatic vinyl-based block copolymer and (b) asphalt, attenuation around 20 to 40 ° C. without lowering the temperature dependence of rigidity near room temperature. Performance can be improved. This is because a polymer block mainly composed of an aromatic vinyl-based compound of an isobutylene-based block copolymer and a high-mixed phase of asphalt with a polymer block mainly composed of an isobutylene-based block copolymer form a polymer block mainly composed of an isobutylene-based block copolymer. This is because a new Tg is expressed in an intermediate region between Tg and Tg of a polymer block containing an aromatic vinyl compound as a main component.

The polymer block containing (a) isobutylene as the main component of the isobutylene-aromatic vinyl block copolymer of the present invention may or may not contain a monomer other than isobutylene. Usually, it is desirable to contain 60% by weight or more, preferably 80% by weight or more of isobutylene. The monomer other than isobutylene is not particularly limited as long as it is a monomer that can be cationically polymerized. For example, aromatic vinyls, dienes, vinyl ethers, β
And monomers such as pinene. These may be used alone or in combination of two or more. As the aromatic vinyl monomer, styrene, α-methylstyrene, p-methylstyrene, pt-butylstyrene,
Inden and the like are exemplified. Examples of the diene monomer include butadiene, isoprene, divinylbenzene, and the like. Examples of the vinyl ether-based monomer include methyl vinyl ether, ethyl vinyl ether, (n-, iso) propyl vinyl ether, (n-, sec-, tert-, iso) butyl vinyl ether, and the like.

In the polymer block mainly comprising an aromatic vinyl compound of the present invention, at least one monomer selected from the group consisting of styrene, α-methylstyrene, p-methylstyrene and indene is used. It is preferable to use styrene, α-methylstyrene, or a mixture thereof in terms of cost. The polymer block containing an aromatic vinyl compound as a main component may or may not contain a monomer other than the aromatic vinyl compound, and the content of the aromatic vinyl compound is 60%. It is desirably at least 80% by weight, preferably at least 80% by weight. The monomer other than the aromatic vinyl compound is not particularly limited as long as it is a monomer component capable of cationic polymerization, and examples thereof include monomers such as isobutylene, dienes, vinyl ethers, and β-pinene. These may be used alone or in combination of two or more.

The proportion of the polymer block containing isobutylene as a main component and the polymer block containing an aromatic vinyl compound as a main component is not particularly limited. The proportion of the polymer block containing as a main component is preferably from 5% by weight to 60% by weight, particularly preferably from 15% by weight to 40% by weight.

The preferred structure of the (a) isobutylene-aromatic vinyl block copolymer of the present invention is preferably an aromatic vinyl compound in view of the mechanical properties, moldability, and other various physical properties of the rubber composition obtained. Triblock copolymer formed from a polymer block composed mainly of-a polymer block composed mainly of isobutylene-a polymer block composed mainly of an aromatic vinyl compound, and a main component composed of an aromatic vinyl compound Diblock copolymer formed from a polymer block composed mainly of isobutylene and a polymer block composed mainly of isobutylene, and a polymer block composed mainly of an aromatic vinyl compound and a polymer block composed mainly of isobutylene At least one selected from the group consisting of star-shaped polymers having a diblock copolymer formed as an arm
Is a seed.

(A) The number average molecular weight of the isobutylene-aromatic vinyl-based block copolymer is not particularly limited. However, from the viewpoint of fluidity, processability, physical properties, etc., it is 3,000 to 10,000.
00, particularly preferably 5,000 to 500,000. If the number average molecular weight of the isobutylene-based block copolymer is lower than the above range, the physical properties of the rubber composition are not sufficiently exhibited, while if it exceeds the above range, it is disadvantageous in terms of fluidity and processability. .

(A) The method for producing the isobutylene-aromatic vinyl-based block copolymer is not particularly limited, and any known polymerization method can be used. Has the following general formula (1)
It is preferable to polymerize a monomer mainly composed of isobutylene and a monomer mainly composed of an aromatic vinyl compound in the presence of the compound represented by (CR ¹ R ² X) _n R ³ (1) In the formula, X represents a substituent selected from the group consisting of a halogen atom, an alkoxyl group having 1 to 6 carbon atoms, and an acyloxyl group having 1 to 6 carbon atoms. R ¹ and R ² each represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms. R ¹
And R ² may be the same or different. R
³ represents a polyvalent aromatic hydrocarbon group or a polyvalent aliphatic hydrocarbon group which can have n substituents. n is
Represents a natural number of 1 to 6.

The compound represented by the general formula (1) serves as an initiator, and generates a carbon cation in the presence of a Lewis acid or the like, and is considered to be a starting point of cationic polymerization. Examples of the compound represented by the general formula (1) include the following compounds. (1-Chloro-1-methylethyl) benzene [C ₆ H ₅ C
(CH ₃ ) ₂ Cl] 1,4-bis (1-chloro-1-methylethyl) benzene [1,4-Cl (CH ₃ ) ₂ CC ₆ H ₄ C (CH ₃ ) ₂ Cl] 1,3 5-tris (1-chloro-1-methylethyl)
In benzene _{[1,3,5- (ClC (CH 3)} 2) 3 C 6 H 3] The polymerization reaction can coexist Lewis acid catalyst. Examples of Lewis acids include TiCl ₄ , BCl ₃ , S
Metal halides such as nCl ₄ are exemplified, and it is desirable to select them in consideration of the polymerization characteristics of the monomers used. The amount of the Lewis acid catalyst to be used is not particularly limited, and can be set in consideration of the polymerization characteristics or polymerization concentration of the monomer used.

In the above polymerization reaction, an electron donor component may be further co-present if necessary. This electron donor component is considered to have an effect of stabilizing the growing carbon cation during cationic polymerization,
The addition of an electron donor produces a polymer having a controlled structure with a narrow molecular weight distribution. The usable electron donor component is not particularly limited, and examples thereof include pyridines, amines, amides, sulfoxides, esters, and metal compounds having an oxygen atom bonded to a metal atom. The polymerization reaction may be performed in a batch system (batch system or semi-batch system), or may be performed in a continuous system in which components required for the polymerization reaction are continuously added into a polymerization vessel.

As the asphalt (b) used in the present invention, straight asphalt, semi-pron asphalt, prawn asphalt, cutback asphalt, tar, pitch and asphalt emulsion can be used. These may be used alone or as a mixture. The asphalt used in the present invention has a penetration of 30 to 300, particularly 4
Those having 0 to 200 are preferred.

The mixing ratio of (a) isobutylene-aromatic vinyl-based block copolymer and (b) asphalt in the vibration damping composition is by weight ratio, and (a) :( b) = 5: 95-
The ratio may be in the range of 90:10, preferably 10: 9.
0:80:20, more preferably 40: 6
0 to 60:40.

If the proportion of the isobutylene-based block copolymer in the composition is 5% or less, the flexibility of the damping material composition is low, and the shear deformation ability is undesirably reduced. On the other hand, if the content of the isobutylene-based block copolymer is 90% or more, the characteristic viscoelasticity of the asphalt component is not exhibited, which is not preferable.

The vibration damping composition of the present invention contains any other components as long as it is a composition comprising (a) an isobutylene-aromatic vinyl-based block copolymer and (b) asphalt. You may. For example, a plasticizer, a tackifier resin, a filler, a thermoplastic resin and the like are exemplified.

Examples of the plasticizer include petroleum-based process oils such as paraffin-based process oils, naphthene-based process oils, and aromatic-based process oils; diethyl phthalate;
Examples thereof include dialkyl dibasic acids such as dioctyl phthalate and dibutyl adipate, and low molecular weight liquid polymers such as liquid polybutene and liquid polyisoprene, and any of these can be used. Such a plasticizer has an effect of moving the Tg of a polymer block containing isobutylene as a main component to a lower temperature side, and in order to achieve such an object, an isobutylene-aromatic vinyl-based block copolymer is used. It is desirable to add a plasticizer compatible with the polymer block containing isobutylene as a main component, and paraffin-based process oil and liquid polybutene are preferably used.

The tackifier resin has a number average molecular weight of 30.
A low-molecular resin having a softening point of 60 to 150 ° C. based on the ring and ball method defined in JIS K-2207, comprising rosin and a rosin derivative, a polyterpene resin, an aromatic modified terpene resin, and a hydride thereof. ,
Terpene phenolic resin, coumarone / indene resin, aliphatic petroleum resin, alicyclic petroleum resin and hydride thereof, aromatic petroleum resin and hydride thereof, aliphatic aromatic copolymer petroleum resin, dicyclopentadiene type Examples are petroleum resins and their hydrides, low molecular weight polymers of styrene or substituted styrene. Such a tackifier resin has a Tg of a polymer block containing isobutylene as a main component.
Has the effect of moving to a higher temperature side, and in order to achieve such an object, a tackifier resin compatible with a polymer block containing isobutylene as a main component in an isobutylene-aromatic vinyl-based block copolymer is used. It is preferable to use, for example, an alicyclic petroleum resin and a hydride thereof, an aliphatic petroleum resin, a hydride of an aromatic petroleum resin, a polyterpene resin, and the like. Further, even in the same type of tackifying resin, as the softening point becomes higher, the effect of moving the Tg of the polymer block containing isobutylene as a monomer main component of the isobutylene-aromatic vinyl-based block copolymer to the higher temperature side is obtained. If the amount of the tackifier resin is to be reduced, a resin having a high softening point may be selected, and if it is desired to increase, a resin having a low softening point may be selected.

Examples of the filler include powder fillers such as mica, carbon black, silica, calcium carbonate, talc, graphite, stainless steel, and aluminum; and fibrous fillers such as glass fibers and metal fibers. . Among them, mica is preferable because it has an effect of improving the damping property. In addition, spot welding becomes possible by incorporating various metal powders such as stainless steel powder and aluminum powder, metal fibers, or conductive particles such as carbon black and graphite.

As the thermoplastic resin, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-
Hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, natural rubber, diene Polymer rubber, olefin polymer rubber,
Acrylic rubber, urethane rubber and the like are exemplified. Examples of the diene rubber include isoprene rubber, butadiene rubber, 1,
Examples thereof include 2-polybutadiene, styrene-butadiene rubber, chloroprene rubber, and nitrile rubber. Examples of the olefin rubber include butyl rubber, halogenated butyl rubber, ethylene-propylene-diene rubber, and the like. Among these, from the viewpoint of compatibility with the isobutylene-based block copolymer, ethylene-propylene copolymer,
Ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, high density polyethylene, low density polyethylene, linear low Ethylene copolymers such as high density polyethylene are preferred.

Examples of other compounding agents include stabilizers such as triphenyl phosphite, hindered phenol and dibutyltin maleate; lubricants such as polyethylene wax, polypropylene wax and montanic acid wax;
Flame retardants such as triphenyl phosphate, tricresyl phosphate, decabromobiphenyl, decabromobiphenyl ether, and antimony trioxide; and pigments such as titanium oxide, zinc sulfide, and zinc oxide.

The vibration damping composition of the present invention comprises the above-mentioned (a) isobutylene-aromatic vinyl block copolymer and (b)
In addition to asphalt as a main component, the ratio of the storage elastic modulus (G ′) obtained at 10 ° C. to the value at 30 ° C. obtained by dynamic viscoelasticity measurement in a shear mode (G ′ ₁₀ ° C. /
G ′ ₃₀ ° C.) is 7 or less, and the loss tangent (tan δ) obtained by the above measurement is preferably 0.4 or more at 10 ° C. to 30 ° C.

The dynamic viscoelasticity measurement in the shear mode is performed according to JIS.
What is necessary is just to carry out according to K-6394 (dynamic property test method of vulcanized rubber and thermoplastic rubber). At this time, the frequency needs to be 0.1 to 5 Hz. This corresponds to the frequency of vibrations caused by earthquakes and typhoons on buildings. Thus, the storage elastic modulus (G ′) and the loss tangent (tan) obtained by performing the dynamic viscoelasticity measurement in the shear mode are described.
δ) corresponds to an equivalent rigidity (Keq) and an equivalent damping constant (heq) used in the construction field, and G ′ = Keq, tanδ
= 2 · heq. G '
Represents the rigidity of the damping material, and the larger the value, the higher the rigidity. On the other hand, tan δ represents the damping property of the vibration damping material, and the larger the value, the higher the damping property.

As described above, used as a vibration damper
To achieve this, damping near room temperature and temperature dependence of stiffness
Required. The vibration damping composition of the present invention is at 10 ° C.
G 'value (G'_Ten° C) and the value of G 'at 30 ° C (G'
₃₀° C) (G '_Ten° C / G ' ₃₀℃) is 7 or less
Is preferably, and more preferably 4 or less, and 2 or less.
Most preferably below. Also used in the present invention
The composition has a value of tan δ at 10 ° C. to 30 ° C.
0.4 or more, preferably 0.5 or more
Is more preferred, and most preferably 0.7 or more.
New

The method for producing the composition used in the present invention is as follows.
There is no particular limitation, and a method of mechanically mixing using a melting pot equipped with a roll, a Banbury mixer, a kneader, a stirrer, or a single-screw or twin-screw extruder can be used. At this time, heating can be performed if necessary. Also, put the compounding agent in a suitable solvent,
After stirring to obtain a uniform solution of the composition, the solvent may be distilled off. Further, if necessary, the vibration damping material composition can be molded and cross-linked by a press machine or the like.

The vibration damping composition of the present invention can be used as a vibration damper for buildings in combination with a steel plate or a steel pipe. The material of the steel plate or the steel pipe used for the vibration damper is not particularly limited, and examples thereof include a general structural steel plate, a cold-rolled steel plate, a carbon steel plate, a stainless steel plate, and a low alloy steel plate. In addition, the structure of the damping damper, using the damping material composition of the present invention as a damping material, a structure in which at least one damping material and more steel plates are alternately laminated, or It is preferable that at least one damping material and more steel pipes are alternately laminated concentrically.

[0035]

The present invention will be described more specifically with reference to the following examples. It should be noted that the present invention is not limited in any way by these embodiments, and can be appropriately changed and implemented without changing the gist thereof.

(Production Example 1) [Styrene-isobutylene-
Production of Styrene-Triblock Copolymer] In a 2 L reaction vessel equipped with a stirrer, 570 mL of methylcyclohexane (dried by molecular sieves), n-
590 mL of butyl chloride (dried with molecular sieves) and 0.400 g of dicumyl chloride were added. After cooling the reaction vessel to −70 ° C., 0.34 mL of α-picoline (2-methylpyridine) and isobutylene 1
74 mL was added. 10.3 mL of titanium tetrachloride
Was added to initiate polymerization, and the mixture was reacted at −70 ° C. for 2.0 hours while stirring the solution. Then, styrene 58 was added to the reaction solution.
After adding mL and continuing the reaction for another 60 minutes, a large amount of methanol was added to stop the reaction. After removing the solvent and the like from the reaction solution, the polymer was dissolved in toluene and
Washed twice. This toluene solution was added to the methanol mixture to precipitate a polymer, and the obtained polymer was treated at 60 ° C. for 24 hours.
After vacuum drying for an hour, an isobutylene-aromatic vinyl block copolymer was obtained (hereinafter abbreviated as SIBS).

The number average molecular weight of the obtained SIBS is 98,
000, and the molecular weight distribution was 1.15. The number average molecular weight was measured using a Waters 510 type GPC system (chloroform was used as a solvent, and the flow rate was 1 mL / min), and the value in terms of polystyrene was shown.

(Examples 1 to 3) SIB manufactured in the manufacturing example
S, straight asphalt (Storus 60/80, manufactured by Fujikosan), aromatic process oil (AROMAX
1, manufactured by Fuji Kosan Co., Ltd. at 170 ° C. at the compounding ratio shown in Table 1.
Was kneaded with a Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.) for 15 minutes to produce a rubber composition. The rubber composition was
It was compression molded at 0 ° C. to produce a sheet. The moldability was extremely good. A test piece having a length of 6 mm, a width of 5 mm and a thickness of 2 mm was cut out from the sheet, and a dynamic viscoelasticity measuring device DVA was cut out.
Using -200 (manufactured by IT Measurement Control Co., Ltd.), the storage elastic modulus G ′ and the loss tangent tan δ were measured. The measurement frequency was 0.5 Hz.

Comparative Example 1 As a comparative example, only SIBS was compression-molded in the same manner as in Examples 1 to 3 to produce a sheet. Using this sheet, the storage elastic modulus G ′, the loss tangent t
anδ was measured. The measurement frequency was 0.5 Hz.

Comparative Example 2 As a comparative example, only asphalt was compression-molded in the same manner as in Examples 1 to 3 to produce a sheet. Using the sheet, the storage elastic modulus G ′ and the loss tangent tan δ were measured. The measurement frequency was 0.5 Hz.

Examples 1 and 2 were compared with Comparative Example 1 by 10
Tan δ at 30 ° C. to 30 ° C. is remarkable, and
G ′ ₁₀ ° C./G ′ ₃₀ ° C. is 7.0 or less, which is very excellent in the temperature dependency of G ′ near room temperature. Comparative Example 2
Has a large tan δ at 10 ° C. to 30 ° C. and is very excellent in attenuation, but has a very large G ′ ₁₀ ° C./G ′ ₃₀ ° C. of 68.0, and poor G ′ temperature dependence near room temperature. Therefore, it is obviously unsuitable for use as a building damper.

[0042]

The vibration damping composition of the present invention has a temperature of 10 to 30 ° C.
By improving the damping properties at the room temperature, the damping properties at around room temperature and the balance of inconsistent properties such as temperature dependence of rigidity are excellent, and by using the damping material composition of the present invention as a damping material. An inexpensive and excellent building vibration damper can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16F 15/08 F16F 15/08 DF Term (Reference) 2E001 DG01 3J048 AA01 BD04 BD08 EA38 4J002 AE053 AF023 AG00X BA003 BA013 BB173 BC013 BK003 BL023 BP03W CE003 EH096 EH146 FD010 FD023 FD026 FD030 FD090 FD110 FD130 FD170 FD343 FD346 GL00 GN00

Claims (6)

[Claims] 1. A block copolymer comprising (a) a polymer block containing isobutylene as a main component and a polymer block containing an aromatic vinyl compound as a main component, and (b) asphalt. b) is 5: 95-9 by weight
0:10, a vibration damping composition. 2. The ratio of (a) :( b) is 10: 90-8 by weight.
The vibration damping composition according to claim 1, wherein the ratio is 0:20. 3. The weight ratio of (a) :( b) is 40: 60-6.
The vibration damping composition according to claim 1, wherein the ratio is 0:40. 4. The vibration damping composition according to claim 1, further comprising at least one selected from a plasticizer and a tackifier resin. 5. A storage modulus (G ′) obtained by dynamic viscoelasticity measurement in a shear mode at a ratio of 10 ° C. to 30 ° C. (G ′ ₁₀ ° C./G ′ ₃₀ ° C.) of 7 or less; And the loss tangent (tan δ) obtained in the above-mentioned measurement is 10 ° C to 30 ° C.
The vibration damping composition according to any one of claims 1 to 4, which is 0.4 or more. 6. A vibration damper using the vibration damping material composition according to any one of claims 1 to 5.