JPH04218553A - Composition for complex type vibration damper - Google Patents

Abstract

PURPOSE:To obtain a composition for complex type vibration damper suitable for manufacturing a complex type vibration damper providing excellent vibration-damping properties not only in a normal temperature range but also in a temperature range up to high temperature range, having extremely excellent adhesiveness to metallic materials and excellent water resistance. CONSTITUTION:20-95 pts.wt. modified block copolymer obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a functional group-containing vinyl compound is blended with 5-80 pts.wt. vinyl aromatic hydrocarbon-based polymer comprising a vinyl aromatic hydrocarbon and a functional group-containing vinyl compound to give 100 pts.wt. composition, which is mixed with 10-150 pts.wt. tackifier resin having <=160 deg.C softening point to give a composition for complex type vibration-damper.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a composite vibration damping material composition used at high temperatures from room temperature to about 100°C, and more specifically, the present invention relates to compositions for composite vibration damping materials used at high temperatures from room temperature to about 100°C. It is used to manufacture composite vibration damping materials with high vibration absorption performance that can reduce these vibrations and reduce noise when used at high temperatures from room temperature to about 100 degrees Celsius. The present invention relates to a composition.

0002

[Background Art] In recent years, with the development of transportation systems and the proximity of residences to factories, noise and vibration problems have become a social problem as pollution. and vibrations. In response to such trends, there is a demand for providing vibration damping performance to rigid substrates such as metal materials that are sources of noise and vibration, and to improve the vibration damping performance.

[0003] Therefore, one of the conventional materials that exhibits such vibration damping performance is a composite vibration damping material having a three-layer structure in which a viscoelastic intermediate layer made of a viscoelastic resin is sandwiched between two rigid substrates. For example, if the rigid substrate is metal, it can be used for automobile oil pans, engine covers, dashboard panels and floors, hopper chutes, conveyor equipment stoppers, home appliances,
It has been studied and adopted in various other applications, such as vibration reduction members for metal processing machines and structural members of precision machines where vibration prevention is desired.

[0004] In this case, the metal materials constituting the two metal layers may be any metal material that can face each other and sandwich a viscoelastic resin between them to form a damping material.
Examples include two metal plates, two concentric metal tubes, two sections, two molded bodies that can be stacked on top of each other, a metal molded body and a backing plate, and other two-layered structures. . The metal forming the metal layer here is not particularly limited, but usually includes iron, aluminum, copper, lead, or alloys containing these as one component, as well as zinc, tin, chromium, etc. It may also be a metal material plated with epoxy resin, a melamine resin, or the like.

[0005] As the viscoelastic resin constituting the viscoelastic intermediate layer of such a composite vibration damping material, a polyester resin or a resin composition consisting of a polyester resin and a polyolefin resin (Japanese Unexamined Patent Application Publication No. 61-89, 842), a resin composition consisting of an amorphous polyester resin and a low-crystalline polyester resin (Japanese Unexamined Patent Publication No. 62-18,160), an acrylonitrile-butadiene copolymer (Japanese Unexamined Patent Publication No. 60-245, No. 550), compositions consisting of hydroxyl group-containing liquid diene polymers (Japanese Patent Application Laid-open No. 60-190-
No. 350, JP-A-61-207,746, JP-A-61
-261,040, JP-A No. 62-167,042), ethylene/maleic anhydride copolymer and/or
Or a composition consisting of a ternary copolymer of ethylene, maleic anhydride, and alkyl (meth)acrylate (JP-A-62-4
6,638, Japanese Patent Application Laid-open No. 62-46,639)
Also, a composition comprising a styrene copolymer and an olefin copolymer (Japanese Unexamined Patent Publication No. 62-64,844) has been proposed.

By the way, the first characteristic required of such a composite damping material is high damping performance, which is generally expressed by the magnitude of the loss coefficient. Secondly, since the composite vibration damping material is used as a structural member and is also subjected to secondary processing such as press processing, the adhesive strength between it and the viscoelastic intermediate layer made of viscoelastic resin is important, especially in terms of shear resistance. One example is that it has high adhesive strength. Furthermore, thirdly, the composite vibration damping material subjected to press processing may undergo a baking coating process in which it is heated to about 200°C, and the intermediate layer resin composition does not flow out at around this temperature. It is required to have water resistance so that the intermediate layer resin composition will not be damaged by water or the like and the adhesive strength will not be significantly reduced when used in practical use.

[0007] In particular, in the case of damping materials that exhibit excellent damping performance in the temperature range from normal temperature to high temperature from 0 to 100°C,
The glass transition region of the viscoelastic intermediate layer resin composition must be around or below room temperature, and the composition has a low elastic modulus at room temperature. On the other hand, compositions exhibiting a high elastic modulus are generally superior in terms of shear adhesive strength, which has an important effect on press workability. In other words, the vibration damping performance required for composite vibration damping materials and the shear adhesive strength related to press workability are contradictory properties regarding the elastic modulus of the viscoelastic intermediate layer resin, and the durability is also low. Durability against is also a very strict requirement. Composite vibration damping materials manufactured using the above-mentioned conventional viscoelastic compositions cannot fully satisfy both characteristics of damping performance and shear adhesive strength, as well as water resistance. This is insufficient.

For example, among the above-mentioned conventional techniques, Japanese Patent Laid-Open No. 62-46,638 and Japanese Patent Laid-Open No. 62-46,6
The technologies described in Publication No. 39 have excellent damping performance in high temperature ranges, but have low damping performance in room temperature ranges, and are not suitable for compositions for composite vibration damping materials used in temperature ranges from room temperature to high temperatures. As a matter of fact, it is not completely satisfying. In addition, the technology described in JP-A-59-80,454 uses a crystalline polyolefin modified with an unsaturated carboxylic acid and an amorphous polymer as essential components; Crystalline polyolefins modified with unsaturated carboxylic acids have extremely low vibration damping performance in the temperature range from room temperature to high temperatures due to their crystallinity, and even when combined with amorphous polymers, the vibration damping performance from room temperature to high temperatures The damping properties in the temperature range of 200 to 300 are still low, and the composition is not fully satisfactory as a composite vibration damping material composition.

Furthermore, in the case of the composition made of polyester resin disclosed in JP-A No. 62-18,160, its water resistance is insufficient due to its hydrophilic nature, and it is not suitable as a composition for composite vibration damping materials. It's not satisfying.

0010

[Problems to be Solved by the Invention] Therefore, the present inventors have conducted extensive studies to obtain a composite vibration damping material that does not have the above-mentioned problems, and have developed a block copolymer of conjugated diene and vinyl aromatic hydrocarbon. A modified block copolymer modified with a vinyl compound having a functional group, a vinyl aromatic hydrocarbon polymer consisting of a vinyl aromatic hydrocarbon and a vinyl compound having a functional group, and a specific tackifier resin. It has been discovered that a composite vibration damping material using a composition made of the above as a viscoelastic intermediate layer has an excellent balance of damping properties and adhesive strength in the temperature range from room temperature to high temperatures, and has excellent water resistance. We have arrived at the present invention.

[0011] Therefore, the object of the present invention is to provide excellent vibration damping properties particularly in the temperature range from low temperatures to room temperature ranges and furthermore to high temperature ranges of about 100°C, and to provide extremely good adhesion to metal materials. It is an object of the present invention to provide a composition for a composite vibration damping material that is suitable for manufacturing a composite vibration damping material that has the following characteristics and has excellent water resistance.

0012

[Means for Solving the Problems] That is, the present invention provides 20 to 95 parts by weight of a modified block copolymer A obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group; With respect to 100 parts by weight of a composition obtained by blending 5 to 80 parts by weight of vinyl aromatic hydrocarbon polymer B consisting of a vinyl aromatic hydrocarbon and a vinyl compound having a functional group, the softening point is 160°C. A composite vibration damping material composition containing 10 to 150 parts by weight of the following tackifying resin, and a crosslinking agent capable of reacting with the functional group of the vinyl compound in the polymer A and/or polymer B. It is a composite vibration damping material composition containing 0.01 to 40 parts by weight of polymers A and B based on 100 parts by weight of the total amount (A+B), and further contains a block copolymer of conjugated diene and vinyl aromatic hydrocarbon. This is a composition for a composite vibration damping material, which is a hydrogenated modified block copolymer obtained by hydrogenating a modified block copolymer A in which the polymer is modified with a vinyl compound having a functional group.

The present invention will be explained in detail below. First, the composite vibration damping material in the present invention has a so-called three-layer structure in which two metal layers are sandwiched between them and a viscoelastic intermediate layer that connects these metal layers to each other. It is.

The first component of the resin composition forming this viscoelastic intermediate layer is a modified block copolymer A obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group. be. Such modified block polymer A is a block copolymer containing at least one polymer block of a conjugated diene compound, at least one polymer block, preferably two or more polymer blocks of vinyl aromatic hydrocarbon, and a functional group. It is a thermoplastic elastomer modified with a vinyl compound, and is a polymer that has thermoplasticity at fairly high temperatures and has rubber properties at room temperature.

In the modified block copolymer A, the weight ratio of the conjugated diene compound to the vinyl aromatic compound is 95/
The range of 5 to 60/40 is preferable, and the number average molecular weight is 10
,000 to 100,000 is preferred. Further, the molecular structure thereof may be linear, branched, radial, or a combination thereof.

In the present invention, the conjugated diene compound constituting the block copolymer A is one having 4 to 8 carbon atoms, such as butadiene, isoprene, 2,3-dimethyl-1
, 3-butadiene, 1,3-pentadiene, etc., but a preferred conjugated diene is butadiene. Examples of vinyl aromatic hydrocarbons include styrene, o-methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, α-methylstyrene, and vinyl naphthalene. Preferred vinyl aromatic hydrocarbons include It is styrene.

The block copolymer used in the present invention is generally synthesized by anionic living polymerization using an organolithium compound as a catalyst in an inert hydrocarbon solvent such as benzene. In addition, modification with a vinyl compound having a functional group,
There is no particular limitation on the manufacturing method, and it can generally be achieved by adding a functional group-containing vinyl compound in a solution or molten state with or without the use of a radical initiator.

Next, as the above functional group-containing vinyl compound, α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, cis-4-cyclohexene-1,2-carboxylic acid, etc. Examples include alicyclic unsaturated carboxylic acids and their anhydrides, esters, amides, imides, and derivatives of metal salts. Further, examples include vinyl group-containing silane compounds such as vinyltriethoxysilane and γ-methacryloxypropyltrimethoxysilane, and vinyl group-containing nitrogen compounds such as N-vinylcaprolactam and N-vinylsuccinimide. The vinyl compound contained is maleic anhydride.

The reason why it is necessary to modify the block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group in the present invention is that the block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon is modified with a vinyl compound having a functional group. In addition, when a crosslinking agent that can react with the functional group is added, this functional group and the crosslinking agent react, changing the block copolymer from thermoplastic to thermosetting. This is because it is possible to significantly improve heat resistance and oil resistance, and also to further improve adhesive strength.

Furthermore, it is more preferable that the modified block copolymer is hydrogenated. The reason for this is that the unsaturated bonds derived from the conjugated diene in the modified block copolymer are hydrogenated, which significantly improves its mechanical strength and makes it extremely stable against heat, making it difficult to bake paints. This is because excellent heat resistance can be imparted, with almost no decrease in adhesive strength even after drying.

[0021] Further, hydrogenation in this method for producing a hydrogenated modified block copolymer is generally performed by hydrogenating the block copolymer in a solution or molten state using a catalyst such as Ni, Pd, or Co. This is achieved by

On the other hand, the second component used together with the modified block copolymer A is a vinyl aromatic hydrocarbon polymer B consisting of a vinyl aromatic hydrocarbon and a vinyl compound having a functional group. The vinyl compound having a functional group in the polymer B is incorporated into the vinyl aromatic hydrocarbon polymer by addition or copolymerization as a copolymerization component. The weight ratio of the vinyl aromatic hydrocarbon to the vinyl compound having a functional group in the vinyl aromatic hydrocarbon polymer B is preferably in the range of 99.9/0.1 to 70/30.

Examples of the vinyl aromatic hydrocarbon constituting the vinyl aromatic hydrocarbon polymer B include the compounds mentioned in the description of the block copolymer A above, and preferred vinyl aromatic hydrocarbons include It is styrene. Similarly, as a functional group-containing vinyl compound, block copolymer A
The preferred functional group-containing vinyl compound is maleic anhydride. However, the above-mentioned block copolymer A and vinyl aromatic hydrocarbon polymer B
It is not necessary that the functional group-containing vinyl compounds therein be the same. Furthermore, the vinyl aromatic hydrocarbon polymer B may contain thermoplastic rubber, unvulcanized rubber, or a low polymer thereof. Furthermore, the reason why the vinyl aromatic hydrocarbon polymer B contains a functional group-containing vinyl compound is the same as that for the block copolymer A described above.

[0024] There are no restrictions on the method for producing the vinyl aromatic hydrocarbon polymer B, and in the case of modification with a vinyl compound having a functional group, a radical initiator is generally used in a solution or molten state, or a radical initiator is not used. This can be achieved by adding a vinyl compound with a functional group,
In the case of a copolymer, it can generally be achieved by a polymerization method such as solution polymerization or bulk polymerization.

Furthermore, the third component used together with the modified block copolymer A and the vinyl aromatic polymer B in the present invention is a tackifying resin having a softening point of 160° C. or less. A tackifier resin with a softening point exceeding 160° C. will have a strong adhesive strength (T-peel, shear), but its damping properties at room temperature will be significantly reduced, making it unusable.

[0026] As the tackifier resin having a softening point of 160°C or less used in the present invention, terpene resins such as terpene and hydrogenated terpene, rosin resins such as rosin, rosin ester, and hydrogenated rosin ester, aliphatic petroleum resins, Examples include aromatic petroleum resins and petroleum resins such as polydicyclopentadiene, among which terpenes, hydrogenated terpene resins, and aliphatic petroleum resins are particularly preferred.

The reason why three resin components, namely the modified block copolymer A, the vinyl aromatic hydrocarbon polymer B and the tackifier resin, are used in the present invention is as follows. In other words, modified block copolymer A has excellent adhesive strength when used alone, but has low vibration damping properties from room temperature to high temperature range, and vinyl aromatic hydrocarbon polymer B is extremely hard when used alone, and the tackifying resin also has poor vibration damping properties. When used alone, it is extremely hard and brittle, so it cannot be used as a damping material for applications ranging from room temperature to high temperatures. However, by blending these three, the tackifying resin acts on the modified block copolymer A and the vinyl aromatic hydrocarbon polymer B, increasing flexibility and improving vibration damping properties from room temperature to high temperature range. At the same time, since the vinyl aromatic hydrocarbon polymer B, which has a very strong tensile strength, coexists, it can become a material for reinforcing adhesive strength (particularly shear adhesive strength). Furthermore, each resin originally has excellent water resistance, and by blending these three resins, a material with excellent water resistance can be obtained.

Furthermore, the blending ratio of the modified block copolymer A and the vinyl aromatic hydrocarbon polymer B is such that, in 100 parts by weight of the total amount of A and B, the modified block copolymer A is 2 parts by weight.
The amount is 0 to 95 parts by weight, preferably 40 to 90 parts by weight. The blending ratio of the tackifier resin is 10 to 150 parts by weight, preferably 2 parts by weight, based on 100 parts by weight of the total amount of A and B.
It is 0 to 120 parts by weight. If the blending ratio of the three resins deviates from the range specified in the present invention, the damping properties and/or adhesive strength from room temperature to high temperatures will be low, making it impossible to obtain an excellent composite vibration damping material composition. I can't.

In the present invention, it is also possible to incorporate a crosslinking agent into the composition. This crosslinking agent is a functional group derived from a functional group-containing vinyl compound that is a component of the modified block copolymer A and/or a functional group derived from a functional group-containing vinyl compound that is a component of the vinyl aromatic polymer B. The crosslinking reaction significantly improves the heat resistance of the composition, suppresses the run-off near the baking temperature of the paint, and significantly improves the oil resistance, which was lacking in compositions that do not contain a crosslinking agent. can be done. In addition, adhesive strength (
T-peel and shear) can be further improved, and a very preferable composition can be obtained.

Examples of such crosslinking agents include compounds that can react under specific conditions with the functional groups derived from the functional group-containing vinyl compounds, such as epoxy compounds, amine compounds, isocyanate compounds, metal alcoholate compounds, and guanamine. - Any one type of compound selected from melamine compounds, aziridyl compounds, and oxazoline compounds or a mixture of two or more types can be mentioned. Among these, when the functional group is a carboxylic acid or a carboxylic acid anhydride, isocyanate compounds such as diphenylmethane diisocyanate and epoxy compounds such as bisphenol A type epoxy resin, which are highly reactive with carboxylic acids and carboxylic anhydrides, are particularly preferred.

The amount of these crosslinking agents used varies depending on the type, but the total amount of modified block copolymer A and vinyl aromatic hydrocarbon polymer B (A+B) 100
0.01 to 40 parts by weight, preferably 0.0 parts by weight
It is 1 to 30 parts by weight. If the amount used is less than 0.01 parts by weight, no effect will be obtained, while if it exceeds 40 parts by weight, the composition will become very hard and the damping properties at room temperature will deteriorate, which is not preferable. The crosslinking agent may be blended in any manner or in any order as long as it is within the above blending range.

[0032] Furthermore, the adhesive strength (T-peel,
An inorganic filler may be added to further improve the shearing properties. The inorganic filler used for this purpose is 25
It must be a material that does not thermally decompose even when heated to about 0°C, such as talc, clay, titanium oxide, silica, alumina, mica, zinc white, carbon black, graphite, etc., but it especially improves shear strength. It is preferable to use one or more of talc, clay, silica, and carbon black in order to have a large effect on the carbon black.

The composition of the present invention may also contain the above-mentioned modified block copolymer in order to improve the damping performance or the elastic modulus within a range that does not impair its overall performance as a vibration damping material. Resins other than A, the vinyl aromatic hydrocarbon polymer B, and the tackifying resin may be used in combination. Examples of these resins include polystyrene, AS resin,
Styrenic resins such as ABS resins and SBR (block or random) resins, ethylene/α-olefin copolymers,
Olefin resins such as ethylene/vinyl acetate copolymer, propylene/ethylene copolymer, propylene/butene copolymer, rubber resins such as natural rubber, polyisoprene rubber (IR), butyl rubber (IIR), and polyester. Examples include resins such as elastomers and elastomers such as polyamide elastomers.

Furthermore, a plasticizer may be added in order to shift the glass transition temperature of the resin composition to a desired value. Plasticizers used for this purpose include, for example, polyester plasticizers, polyether ester plasticizers, phosphoric acid esters, epoxy plasticizers, ester plasticizers such as phthalic acid diesters, sebacic acid diesters, etc. Examples include acidic plasticizers, chlorinated paraffins, etc., and are appropriately selected and used depending on the types of modified block copolymer A, vinyl aromatic hydrocarbon polymer B, and tackifier resin used. Furthermore, a coupling agent such as silane or titanium may be added to improve adhesion to metal materials. In order to improve heat resistance, phenol-based, phosphorus-based, sulfur-based, and other antioxidants may be added.

Furthermore, conductivity can be imparted to the viscoelastic composition by blending a conductive solid substance as a filler, and the resulting damping material can be made into a spot weldable material. Conductive substances used for this purpose include metal materials such as stainless steel, zinc, tin, copper, brass, and nickel processed into powder, flake, fiber, wire, etc. . These conductive substances may be used alone, or two or more of them may be used as a mixture. In order to obtain better spot weldability at this time, if the conductive substance is in powder form, the maximum particle size should be adjusted, and if it is in flake form, the maximum thickness should be adjusted. If it is in the form of a fiber, its maximum diameter is taken as its representative length (L), and the ratio (L) of this representative length (L) to the thickness (T) of the intermediate resin layer of the composite vibration damping material. /T) to 0
．． 5 or more, preferably 0.8 or more, more preferably 1.
It is preferable to set it to 0 or more.

The thickness of the viscoelastic intermediate layer formed from the composition of the present invention is appropriately selected depending on the required vibration damping performance, etc., but from the viewpoint of vibration damping performance, it is 10 μm or more, preferably 20 μm or more. The thickness is 300 μm or less, preferably 200 μm or less from the viewpoint of press workability of the composite damping material.

[0037] The method for producing the composite damping material using the composition of the present invention is not particularly limited, and may be any method such as a batch method using a cut plate or a continuous method using a coil. can be adopted. On the other hand, methods for compounding viscoelastic resin and metal materials include methods such as dissolving the viscoelastic resin in a solvent and applying it to the metal material in the form of a paint, and pasting it together using a T-die extruder. Examples include a method of forming an intermediate layer of viscoelastic resin on a metal material, and a method of sandwiching a film-like viscoelastic resin produced offline between metal materials as an intermediate layer and bonding with hot melt adhesive. Any method can be adopted depending on the purpose, such as the properties of the composition or the type of composite damping material to be obtained.

[0038]

EXAMPLES The present invention will be specifically explained below based on Examples and Comparative Examples, but the scope of the present invention is not limited by the Examples.

Examples 1 to 7 and Comparative Examples 1 to 4 Modified block copolymer A used in Examples and Comparative Examples was obtained by modifying a block copolymer of styrene and butadiene with maleic anhydride and hydrogenating it. It is a modified SEBS resin with a weight ratio of styrene and ethylene/butylene of 30/70 and an acid value (
mg, CH3 ONa/g) of 10 (modified S
EBS), and the hydrogenated block copolymer used in the comparative example was a copolymer with the same weight ratio of styrene/ethylene/butylene as the above-mentioned modified hydrogenated block copolymer but not modified with maleic anhydride ( Native SEBS).

Next, the vinyl aromatic hydrocarbon polymer B used in the Examples and Comparative Examples is a copolymer of styrene and maleic anhydride, and the weight ratio of styrene and maleic anhydride is about 91/9. belongs to. As the tackifying resin, a hydrogenated terpene resin with a softening point of 70°C, a coumaron resin with a softening point of 120°C, and a hydrogenated aliphatic petroleum resin with a softening point of 140°C were used. In addition, as a crosslinking agent, the epoxy equivalent is 184 to 19
4 bisphenol A type epoxy resin (Epicote 82
8; manufactured by Yuka Shell Epoxy Co., Ltd.) was used. Furthermore, talc with a particle size of 3 to 4 μm was used as a filler.

[0041] In these Examples and Comparative Examples, the compositions and vibration damping steel plates used for the tests were produced by the following method. Modified hydrogenated block copolymer (modified SEB
S) or a hydrogenated block copolymer (SEBS), a styrene-maleic anhydride copolymer, and a tackifying resin.
Roll kneading was carried out at ~180°C, and when a filler was added, the filler was added and thoroughly kneaded, and the resulting composition was dissolved in xylene to form a paint-type composition. When adding an epoxy resin to this paint type composition, after adding a predetermined amount of epoxy resin and mixing well, the composition was applied onto a cold rolled steel plate using a bar coater and dried at a temperature of 180°C for 3 minutes. They were then overlapped and heat-pressed at a temperature of 150 to 220° C. for 3 minutes to prepare a composite vibration damping material having a viscoelastic resin intermediate layer with a thickness of about 50 μm. The adhesive strength (T-peel and shear) and vibration damping performance of the composite damping material thus prepared were measured. The results are shown in Table 1.

[0042] The T-peel adhesive strength is determined according to JIS K
Evaluated at a tensile speed of 50 mm/min based on the JIS K 6854 test method, and the shear adhesive strength was JIS K 6850.
Evaluation was performed at a tensile speed of 5 mm/min based on the test method. In addition, vibration damping performance is determined by measuring the loss coefficient (η) representing vibration absorption ability using the mechanical impedance method, and measuring the maximum value of η (ηmax
) and the temperature (Tp) at which this ηmax is exhibited.The low-temperature vibration damping performance was evaluated by the loss coefficient (η20 C) at 20°C. Further, water resistance was evaluated by making a predetermined notch in the composite damping material and immersing it in boiling water for 6 hours, and then evaluating the retention rate of shear adhesive strength. Furthermore, the outflow start temperature of the composition was evaluated by applying the paint-type composition onto release paper, drying it at 180° C. for 3 minutes, and peeling it off from the release paper. The outflow start temperature was measured using an elevated flow tester (manufactured by Shimadzu Corporation) with a die diameter of 0.5 mmφ, a die length of 1 mm, and a pressure of 10 kgf/.
It was determined by measuring under the condition of cm2.

[0043]

[Table 1]

From the results in Table 1, Examples 1 to 7 of the present invention have a well-balanced composition that exhibits very high adhesive strength (T-peel, shear) and high vibration damping properties from room temperature to high temperature. The outflow starting temperature is 190°C or higher, and the water resistance is also high. In addition, when a crosslinking agent is added (Examples 3 to 5), the functional groups in the modified hydrogenated block copolymer and the vinyl aromatic polymer react with the crosslinking agent, resulting in a thermosetting composition. On the other hand, there is no leakage of the composition due to heating, and the water resistance is almost perfect.

On the other hand, as shown in the comparative examples, in comparative examples 1 and 2, the vibration damping properties and adhesive strength from room temperature to high temperature were rather low, and the compositions were unsatisfactory in terms of physical properties, and the outflow temperature due to heat was also low. Furthermore, in Comparative Examples 3 and 4 using unmodified hydrogenated block copolymers, the block copolymers did not have functional groups, so the adhesive strength was low, the composition flowed out at about 150° C., and the water resistance was also poor.

From the above results, it was found that a modified block copolymer obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group, a vinyl aromatic hydrocarbon and a vinyl compound having a functional group, A composition consisting of a vinyl aromatic hydrocarbon polymer and a tackifier resin, as well as a composition in which a crosslinking agent is added, has a well-balanced vibration damping performance and adhesive strength (T-peel, shear), and the composition does not flow out even at high temperatures. However, it was found that the composition was an excellent composite vibration damping material composition with improved water resistance.

[0047]

[Effects of the Invention] The composite vibration damping material composition of the present invention has two
The composite vibration damping material obtained by sandwiching between two metal materials has excellent adhesive properties, exhibits excellent vibration damping performance from around room temperature to high temperatures of around 100 degrees Celsius, and has excellent durability (high temperature resistance). It is extremely useful industrially as it exhibits excellent flowability and water resistance).

Claims (3)

[Claims] Claim 1: 20 to 95 parts by weight of a modified block copolymer A obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group, and a vinyl aromatic hydrocarbon and a functional group. 10 to 150 parts by weight of a tackifier resin having a softening point of 160° C. or less per 100 parts by weight of a composition obtained by blending 5 to 80 parts by weight of a vinyl aromatic hydrocarbon polymer B consisting of a vinyl compound. A composition for a composite vibration damping material, characterized in that it contains the following. 2. A crosslinking agent capable of reacting with the functional group of the vinyl compound in the polymer A and/or polymer B is added in an amount of 0.0 parts by weight per 100 parts by weight of the total amount of the polymers A and B (A+B).
2. The composite vibration damping material composition according to claim 1, comprising 1 to 40 parts by weight. 3. The modified block copolymer A obtained by modifying a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon with a vinyl compound having a functional group is a hydrogenated modified block copolymer. Item 2. Composite vibration damping material composition according to item 1 or 2.