JPH0742390B2 - Composition for composite type damping material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for a composite type vibration damping material which is used at a high temperature from room temperature to about 100 ° C., more specifically, a constituent member of a vehicle, an electric part, a machine or a structure, or a component thereof. It is used to manufacture a composite vibration damping material that has a high vibration absorption performance, which constitutes a part of it and reduces these vibrations when used at high temperatures from room temperature to about 100 ° C and can reduce noise. Composition.

[0002]

2. Description of the Related Art In recent years, the problems of noise and vibration have become a social problem as pollution due to the development of transportation facilities and the approach of houses to factories, and noise is also improved in the workplace to improve the working environment. And tends to regulate vibration. In response to such a trend, it is required to impart vibration damping performance to a rigid substrate such as a metal material that is a noise source or a vibration source and to improve the vibration damping performance.

Therefore, as one of the materials that have conventionally exhibited such vibration damping performance, a composite vibration damping having a three-layer structure in which a viscoelastic intermediate layer made of a viscoelastic resin is sandwiched between two rigid substrates. Materials have been proposed, for example, when the rigid substrate is metal, automobile oil pans, engine covers, dashboard panels and floors, hopper chute parts, transport equipment stoppers, home appliances,
In addition, it has been variously studied and adopted as a vibration reducing member of a metal working machine or a structural member of a precision machine for which vibration prevention is desired.

In this case, the metal material constituting the two metal layers may be any metal material which can face each other and sandwich a viscoelastic resin in the middle to form a vibration damping material, for example, 2
Examples include a metal plate, two concentric metal tubes, two shaped steels, two molded bodies that can be stacked on top of each other, a metal molded body and a contact plate, and other materials having a two-layer structure. . And the metal forming the metal layer here is not particularly limited, but usually, iron, aluminum, copper, lead or alloys containing these as one component,
Further, it may be a metal material plated with zinc, tin, chromium or the like, or a material surface-treated with an epoxy resin, a melamine resin or the like.

As a viscoelastic resin forming the viscoelastic intermediate layer of such a composite type vibration damping material, a polyester resin or a resin composition composed of a polyester resin and a polyolefin resin (JP-A-61-89, 842), a resin composition comprising an amorphous polyester resin and a low-crystalline polyester resin (JP-A-62-18,160), and an acrylonitrile-butadiene copolymer (JP-A-60-245, 550) and a composition containing a hydroxyl group-containing liquid diene polymer (JP-A-60-190-).
350, JP-A-61-207,746, JP-A-61
-261,040, JP-A-62-167,042), ethylene / maleic anhydride copolymer and /
Alternatively, a composition comprising a terpolymer of ethylene / maleic anhydride / alkyl (meth) acrylate (JP-A-62-4)
6,638, JP-A-62-46,639)
Alternatively, a composition comprising a styrene-based copolymer and an olefin-based copolymer (JP-A-62-64,844) has been proposed.

By the way, as a characteristic required for such a composite type vibration damping material, first, it is mentioned that the vibration damping performance is high, and this is generally expressed by the magnitude of the loss coefficient. Secondly, since the composite type vibration damping material is used as a structural member and is subjected to secondary processing such as press working, the adhesive strength with the viscoelastic intermediate layer composed of viscoelastic resin, especially shear It has high adhesive strength. Furthermore,
Third, the composite type damping material that has been pressed is 200 ° C.
The intermediate layer resin composition may not flow out around this temperature because it may undergo a baking coating process that is heated to a certain degree, and fourthly, when the intermediate layer resin composition is put into practical use, the intermediate layer resin composition is placed and bonded. Water resistance that does not significantly reduce the force is required.

Particularly, in the case of a damping material which exhibits excellent damping performance in a temperature range of 0 to 100 ° C. from normal temperature to high temperature,
The glass transition region of the viscoelastic intermediate layer resin composition needs to be around room temperature or lower, and the composition has a low elastic modulus at room temperature. On the other hand, the shear adhesive strength, which has an important influence on the press workability, is generally superior to the composition showing a high elastic modulus. That is, the vibration damping performance required for the composite type vibration damping material and the shear adhesive strength related to the press workability are contradictory requirements regarding the elastic modulus of the viscoelastic intermediate layer resin, and the durability is also low. Durability is also a very strict required property. The composite type vibration damping material produced by the above conventional viscoelastic composition cannot fully satisfy both the characteristics of the vibration damping performance and the shear adhesive strength, and the water resistance, and thus the viscoelastic composition for the vibration damping material is used. Is inadequate.

For example, among the above-mentioned conventional techniques, JP-A-62-46,638 and JP-A-62-46,6.
The techniques described in JP-A No. 39 have excellent vibration damping performance in a high temperature region, but have low vibration damping performance in a normal temperature region, and a composition for a composite vibration damping material used in a temperature region from normal temperature to high temperature. The thing is not completely satisfactory. Further, the technique described in JP-A-59-80,454 uses a polymer obtained by modifying a crystalline polyolefin with an unsaturated carboxylic acid and an amorphous polymer as essential components. Crystalline polyolefin modified with unsaturated carboxylic acid has very low vibration damping performance in the temperature range from room temperature to high temperature because of its crystallinity, and even when it is combined with an amorphous polymer, it has high vibration control performance. The vibration damping property in the temperature range is still low, and it is not sufficiently satisfactory as a composite type vibration damping material composition.

Further, in the case of the composition composed of the polyester resin disclosed in JP-A-62-18,160, the hydrophilicity thereof causes insufficient water resistance, and thus it is sufficient as a composition for a composite type vibration damping material. I'm not satisfied.

[0010]

Therefore, as a result of intensive investigations by the present inventors to obtain a composite damping material that does not have the above problems, a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon is obtained. A modified block copolymer obtained by modifying the above with a vinyl compound having a functional group, a vinyl aromatic hydrocarbon-based polymer comprising a vinyl aromatic hydrocarbon and a vinyl compound having a functional group, and a specific tackifying resin are further blended. It was found that the composite vibration damping material using the composition as a viscoelastic intermediate layer has excellent balance between vibration damping property and adhesive strength in a temperature range from normal temperature to high temperature and has excellent water resistance. The present invention has been reached.

Therefore, an object of the present invention is to impart excellent vibration damping properties particularly in a temperature range from low temperature to room temperature, and further to a high temperature range of about 100 ° C., and to achieve extremely good adhesion to metal materials. It is an object of the present invention to provide a composition for a composite type vibration damping material, which is suitable for producing a composite type vibration damping material having excellent water resistance.

[0012]

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. The softening point is 160 ° C. with respect to 100 parts by weight of a composition obtained by mixing 5 to 80 parts by weight of a vinyl aromatic hydrocarbon polymer B composed of a vinyl aromatic hydrocarbon and a vinyl compound having a functional group. A composition for a composite type vibration damping material, which comprises 10 to 150 parts by weight of the following tackifying resin, and a cross-linking agent capable of reacting with the functional group of the vinyl compound in the polymer A and / or the polymer B. A composition for a composite vibration damping material, which comprises 0.01 to 40 parts by weight based on 100 parts by weight of the total amount of the polymers A and B (A + B), and further, a block copolymerization weight of a conjugated diene and a vinyl aromatic hydrocarbon. Coalesce Functional group is a composite vibration-damping material composition modified block copolymer A modified with a vinyl compound is hydrogenated hydrogenated modified block copolymer having.

The present invention will be described in detail below. First, the composite damping material in the present invention has a so-called three-layer structure in which a viscoelastic intermediate layer for joining these two metal layers is sandwiched between two metal layers as described above. Is.

The first component of the resin composition forming the 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. is there. The modified block polymer A has a functional group containing a block copolymer containing at least one polymer block of a conjugated diene compound and at least one polymer block of vinyl aromatic hydrocarbon, and preferably two or more. It is a thermoplastic elastomer modified with a vinyl compound and has a thermoplastic property at a considerably high temperature and a rubber property at a normal 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 1
The range of 50,000 to 100,000 is preferable. Also,
Its molecular structure may be linear, branched, radial or a combination thereof.

The conjugated diene compound constituting the block copolymer A in the present invention has a carbon number of 4 to 8, and includes butadiene, isoprene, 2,3-dimethyl-1,3-butadiene and 1,3- Pentadiene and the like can be mentioned, but a preferred conjugated diene is butadiene. Examples of vinyl aromatic hydrocarbons include styrene, o-methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, α-methylstyrene, vinylnaphthalene, and the like. Suitable vinyl aromatic hydrocarbons are 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. Further, the modification with a vinyl compound having a functional group,
The production method is not particularly limited, and it can be generally achieved by adding a functional group-containing vinyl compound in a solution or in a molten state with or without a radical initiator.

Next, as the functional group-containing vinyl compound, there are α, such as acrylic acid, methacrylic acid, maleic acid, fumaric acid and cis-4-cyclohexene-1,2-carboxylic acid.
Examples thereof include β-unsaturated carboxylic acid, alicyclic unsaturated carboxylic acid and their anhydrides, and derivatives such as esters, amides, imides and metal salts. Further, vinyl triethoxysilane, vinyl group-containing silane compounds such as γ-methacryloxypropyltrimethoxysilane and N-vinyl caprolactam, vinyl group-containing nitrogen compounds such as N-vinyl succinimide, and the like, suitable functional groups The vinyl compound contained is maleic anhydride.

In the present invention, the reason why the block copolymer of the conjugated diene and the vinyl aromatic hydrocarbon needs to be modified with the vinyl compound having the functional group is that the metal compound is modified by the vinyl compound having the functional group. In addition to significantly improving the adhesiveness with, when a cross-linking agent capable of reacting with the functional group is further added, the functional group reacts with the cross-linking agent, so that the block copolymer changes from thermoplasticity to thermosetting. This is because the heat resistance and the oil resistance can be remarkably improved, and the adhesive strength can be further improved.

Further, it is more preferable that the modified block copolymer is hydrogenated. The reason for this is that the unsaturated bond derived from the conjugated diene in the modified block copolymer is hydrogenated, so that the mechanical strength is remarkably improved and it becomes very stable against heat, and the coating is baked. This is because it is possible to impart excellent heat resistance that can almost eliminate the decrease in adhesive strength even after the heating.

The hydrogenation in the method for producing the hydrogenated modified block copolymer is generally carried out by hydrogenating the block copolymer in a solution or a molten state using a catalyst such as Ni, Pd or Co. Achieved by

On the other hand, the second component used together with the modified block copolymer A is a vinyl aromatic hydrocarbon polymer B composed 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 added to the vinyl aromatic hydrocarbon polymer or copolymerized as a copolymerization component to be contained in the polymer. 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 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, and the preferable vinyl aromatic hydrocarbon is It is styrene. Further, as the functional group-containing vinyl compound, the block copolymer A is similarly used.
The functional group-containing vinyl compound is maleic anhydride. However, the above-mentioned block copolymer A and vinyl aromatic hydrocarbon polymer B
The functional group-containing vinyl compounds therein need not be the same.
Further, the vinyl aromatic hydrocarbon polymer B may contain a thermoplastic rubber, an unvulcanized rubber or a low polymer thereof. Further, the reason why the functional group-containing vinyl compound is contained in the vinyl aromatic hydrocarbon polymer B is the same as that of the block copolymer A described above.

The method for producing the vinyl aromatic hydrocarbon polymer B is not limited, and in the case of modification with a vinyl compound having a functional group, a radical initiator is generally used in a solution or a molten state, or is not used. Can be achieved by adding a vinyl compound having a functional group with
In the case of a copolymer, it can be generally achieved by a polymerization method such as solution polymerization or bulk polymerization.

Further, the third component used in the present invention together with the modified block copolymer A and the vinyl aromatic polymer B is a tackifying resin having a softening point of 160 ° C. or lower. With a tackifying resin having a softening point of more than 160 ° C., the adhesive strength (T peeling, shearing) becomes strong, but the vibration damping property at the room temperature side is remarkably lowered and it becomes unusable.

The tackifying resin having a softening point of 160 ° C. or less used in the present invention includes terpene resins such as terpene and hydrogenated terpene, rosin resins such as rosin, rosin ester and hydrogenated rosin ester, and aliphatic petroleum resins, Aromatic petroleum resins, petroleum-based resins such as polydicyclopentadiene and the like can be mentioned, and among them, terpenes, hydrogenated terpene resins or aliphatic petroleum resins are particularly preferable.

The reason why the three resin components, namely the modified block copolymer A, the vinyl aromatic hydrocarbon polymer B and the tackifying resin are used in the present invention, is as follows.
That is, the modified block copolymer A alone has excellent adhesive strength, but has low vibration damping property from room temperature to high temperature range, and the vinyl aromatic hydrocarbon polymer B alone is very hard, and the tackifying resin also Alone, it is extremely hard and brittle and cannot be used as a vibration damping material for applications from room temperature to high temperatures. However, by blending these three components, the tackifying resin acts on the modified block copolymer A and the vinyl aromatic hydrocarbon-based polymer B to increase the flexibility, and the vibration damping property from room temperature to high temperature range is improved. Since the vinyl aromatic hydrocarbon polymer B having extremely strong tensile strength coexists, it can be used as a reinforcing material for adhesive strength (particularly shear adhesive strength). Furthermore, each resin is originally excellent in water resistance, and by blending these three materials, a material having excellent water resistance can be obtained.

The blending ratio of the modified block copolymer A and the vinyl aromatic hydrocarbon polymer B is 2 parts by weight of the modified block copolymer A in a total amount of 100 parts by weight of A and B.
It is 0 to 95 parts by weight, preferably 40 to 90 parts by weight.
The compounding ratio of the tackifying resin is 10 to 150 parts by weight, preferably 2 parts, based on 100 parts by weight of the total amount of A and B.
It is 0 to 120 parts by weight. When the compounding ratio of the three kinds of resins is out of the range specified in the present invention, the vibration damping property and / or the adhesive strength from normal temperature to high temperature region becomes low, and an excellent composition for composite vibration damping material is obtained. I can't.

Further, in the present invention, it is possible to incorporate a crosslinking agent into the composition. This cross-linking agent is a functional group derived from a functional group-containing vinyl compound which is a constituent of the modified block copolymer A and / or a functional group derived from a functional group-containing vinyl compound which is a constituent of the vinyl aromatic polymer B. It is capable of reacting with, and significantly improves the heat resistance of the composition through the crosslinking reaction, suppresses the outflow near the baking temperature of the paint, and significantly improves the oil resistance that was lacking in the composition containing no crosslinking agent. Can be made. Further, the adhesive strength (T peeling, shearing) can be further improved, and a very preferable composition can be obtained.

As such a cross-linking agent, a compound capable of reacting with the functional group derived from the functional group-containing vinyl compound under specific conditions, such as an epoxy compound, an amine compound, an isocyanate compound, a metal alcoholate compound,
Examples thereof include any one compound selected from a guanamine / melamine compound, an aziridyl compound or an oxazoline compound, or a mixture of two or more compounds. Among these, when the functional group is a carboxylic acid or a carboxylic acid anhydride, an isocyanate compound such as diphenylmethane diisocyanate having a high reactivity with these and an epoxy compound such as a bisphenol A type epoxy resin are particularly preferable.

The amount of these cross-linking agents used depends on the type, but the total amount (A + B) of the modified block copolymer A and the vinyl aromatic hydrocarbon polymer B is 100.
0.01 to 40 parts by weight, preferably 0.0
It is 1 to 30 parts by weight. If the amount used is less than 0.01 part by weight, the use effect cannot be obtained. On the other hand, if it exceeds 40 parts by weight, the composition becomes extremely hard and the vibration damping property at room temperature is deteriorated, which is not preferable. The cross-linking agent may have any mixing method, mixing order, or the like as long as it is in the above-mentioned mixing range.

The adhesive strength of the composition of the present invention (T peeling,
An inorganic filler may be further added to further improve (shear). The inorganic filler used for this purpose is 25
It must be one that does not thermally decompose even when heated to approximately 0 ° C, and examples include talc, clay, titanium oxide, silica, alumina, mica, zinc white, carbon black, graphite, etc., but especially shear strength is improved. From the standpoint of great effect, it is preferable to use one or more of talc, clay, silica or carbon black.

Further, the composition of the present invention contains the above-mentioned modified block copolymer for improving the vibration damping performance or the elastic modulus as long as the overall performance as the vibration damping material is not impaired. Resins other than A, the vinyl aromatic hydrocarbon polymer B and the tackifying resin may be mixed and used. Examples of these resins include polystyrene, AS resin,
Styrene resin such as ABS resin and SBR (block or random) resin, and ethylene / α-olefin copolymer,
Olefin resin such as ethylene / vinyl acetate copolymer, propylene / ethylene copolymer, propylene / butene copolymer, rubber resin such as natural rubber, polyisoprene rubber (IR), butyl rubber (IIR), polyester Examples of the resin include elastomers and elastomers such as polyamide elastomers.

Further, a plasticizer may be added in order to shift the glass transition temperature of the resin composition to a desired value. Examples of the plasticizer used for this purpose include polyester plasticizers, polyether ester plasticizers, phosphoric acid esters, epoxy plasticizers, phthalic acid diesters, sebacic acid diesters and other ester plasticizers, and trimellitate. Examples thereof include acid plasticizers and chlorinated paraffins, which are appropriately selected and used according to the types of the modified block copolymer A, vinyl aromatic hydrocarbon polymer B and tackifying resin used. Further, a coupling agent such as silane or titanium may be added in order to improve the adhesiveness with the metal material. Then, in order to improve heat resistance, a phenol-based antioxidant, a phosphorus-based antioxidant, a sulfur-based antioxidant or the like may be added.

Further, by adding a conductive solid substance as a filler to the viscoelastic composition, conductivity can be imparted, and the obtained damping material can be made into a spot-weldable material. Examples of the conductive substance used for such purpose include metal substances obtained by processing metals such as stainless steel, zinc, tin, copper, brass and nickel into powder, flakes, fibers and wires. . These conductive materials may be used alone or in combination of two or more kinds as a mixture. Further, in this case, in order to obtain better spot weldability, the maximum particle diameter of the conductive substance when the conductive substance is in a powder state, the maximum thickness thereof when the conductive substance is in a flake state, and In the case of a fibrous shape, when the maximum diameter is taken as the respective representative length (L), the ratio (L) between the representative length (L) and the thickness (T) of the intermediate resin layer of the composite vibration damping material / T) is 0.5 or more, preferably 0.8 or more, and more preferably 1.0 or more.

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

The method for producing the composite damping material using the composition of the present invention is not particularly limited, and any method such as a batch method using a cutting plate and a continuous method using a coil is used. Can be adopted. On the other hand, as a method for forming a composite of a viscoelastic resin and a metal material, a method in which a viscoelastic resin is dissolved in a solvent to form a paint and applied to a metal material and bonded, or a T-die extruder or the like is used. Examples include a method of forming an intermediate layer of a viscoelastic resin on a metal material, a method of sandwiching a film-shaped viscoelastic resin produced offline as an intermediate layer between metal materials, and adhering by hot melt adhesion. Any method can be adopted depending on the purpose of the properties of the composition or the kind of the composite vibration damping material to be obtained.

[0038]

EXAMPLES The present invention will be specifically described 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 The modified block copolymer A used in Examples and Comparative Examples is
A modified SEBS resin obtained by modifying a block copolymer composed of styrene and butadiene with maleic anhydride and hydrogenation, wherein the weight ratio of styrene to ethylene / butylene is 30/7.
It is a copolymer (modified SEBS) having an acid value of 0 (mg, CH ₃ ONa / g) of 10, and the hydrogenated block copolymer used in the comparative example is the above-mentioned modified hydrogenated block copolymer and styrene / styrene. The weight ratio of ethylene and butylene was the same, and the copolymer was not modified with maleic anhydride (unmodified 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 having a softening point of 70 ° C., a coumarone resin having a softening point of 120 ° C., and a hydrogenated aliphatic petroleum resin having a softening point of 140 ° C. were used. Further, as a cross-linking agent, an epoxy equivalent of 184 to 19
4 bisphenol A type epoxy resin (Epicoat 82
8: Yuka Shell Epoxy Co., Ltd. was used. Further, talc having a particle size of 3 to 4 μm was used as the filler.

In these examples and comparative examples, the compositions and damping steel sheets used for the tests were prepared by the following method. Modified hydrogenated block copolymer (modified SEB
S) or a hydrogenated block copolymer (SEBS), a styrene-maleic anhydride copolymer, and a tackifier resin.
Roll kneading at ˜180 ° C., and when further adding a filler, a filler was added and kneaded well, and the obtained composition was dissolved in xylene to obtain a paint type composition. When an epoxy resin was added to this coating composition, a predetermined amount of the epoxy resin was added and mixed well, then the composition was applied onto a cold-rolled steel sheet using a bar coater and dried at a temperature of 180 ° C. for 3 minutes. The layers were laminated together 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 having a thickness of about 50 μm. With respect to the composite damping material thus prepared, its adhesive strength (T peeling and shearing) and damping performance were measured. The results are shown in Table 1.

The T-peel adhesion strength is JIS K 6
It was evaluated at a pulling speed of 50 mm / min based on the 854 test method, and the shear adhesive strength was evaluated at a pulling speed of 5 mm / min based on the JIS K 6850 test method. Also,
The damping performance is evaluated by measuring the loss coefficient (η) representing the vibration absorption capacity by the mechanical impedance method, measuring the maximum value of η (η _max ) and the temperature (Tp) at which this η _max is exhibited, and The low temperature vibration damping performance was evaluated by the loss coefficient (η _{20 C} ) at 20 ° C. Further, the water resistance was evaluated by holding a predetermined notch in the composite vibration-damping material, immersing the composite vibration-damping material in boiling water for 6 hours, and then evaluating the shear adhesive strength retention rate. Further, the outflow starting temperature of the composition was evaluated by applying a paint-type composition on release paper,
The composition was dried at ℃ for 3 minutes and peeled off from the release paper. The outflow starting temperature was measured and determined using an elevated flow tester (manufactured by Shimadzu Corporation) under conditions of a die diameter of 0.5 mmφ, a die length of 1 mm and a pressure of 10 kgf / cm ² .

[0043]

[Table 1]

From the results shown in Table 1, in Examples 1 to 7 of the present invention, the adhesive strength (T peeling, shearing) is very high, and the vibration damping property from room temperature to high temperature is also high. In addition, the outflow starting temperature shows a value of 190 ° C. or higher, and the water resistance also shows a high value. When a crosslinking agent is added (Examples 3 to 5), the functional groups in the modified hydrogenated block copolymer and vinyl aromatic polymer react with the crosslinking agent to give a thermosetting composition. Instead, there is no outflow of the composition due to heating, and the water resistance is almost complete.

On the other hand, as shown in Comparative Examples, Comparative Examples 1 and 2 are compositions having a slightly low vibration damping property and adhesive strength from room temperature to high temperature, unsatisfactory physical properties, and low outflow temperature due to heat. Further, in Comparative Examples 3 to 4 using the unmodified hydrogenated block copolymer, the block copolymer does not have a functional group, so that the adhesive strength is low and the composition flows out at about 150 ° C. and the water resistance is poor.

From the above results, 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 are used. The composition consisting of the vinyl aromatic hydrocarbon polymer and the tackifying resin, and the composition to which a cross-linking agent is added have a good balance of vibration damping performance and adhesive strength (T peeling, shearing), and the composition flows out even at high temperature. However, it was found that the composition was an excellent composite type vibration damping material composition having improved water resistance.

[0047]

The composition of the composite type vibration damping material of the present invention is 2
Sandwiched between two metal materials, the resulting composite vibration damping material has excellent adhesiveness and exhibits excellent vibration damping performance from around room temperature to a high temperature of about 100 ° C, as well as excellent durability (high temperature resistance). It has excellent runoff and water resistance and is extremely useful in industry.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location C08L 51/04 LKY F16F 1/30 8917-3J (72) Inventor Nobuo Kadowaki Fuchinobe, Sagamihara City, Kanagawa Prefecture 5-10-1, Nippon Steel Corporation Second Research Laboratory

Claims (3)

[Claims] 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 tackifying resin having a softening point of 160 ° C. or lower with respect to 100 parts by weight of a composition obtained by blending 5 to 80 parts by weight of a vinyl aromatic hydrocarbon polymer B composed of a vinyl compound. A composition for a composite vibration damping material, characterized in that: 2. A cross-linking agent capable of reacting with a functional group of a vinyl compound in the polymer A and / or the polymer B is added to the polymer A.
0.01 with respect to 100 parts by weight of the total amount of A and B (A + B)
The composition for a composite vibration damping material according to claim 1, wherein the composition is mixed in an amount of -40 parts by weight. 3. 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, wherein the modified block copolymer A is a hydrogenated hydrogenated modified block copolymer. Item 1. The composition for composite type damping material according to Item 1 or 2.