JP5571332B2 - Primer composition for viscoelastic damper and viscoelastic damper - Google Patents

Description

  The present invention relates to a viscoelastic damper primer composition and a viscoelastic damper containing the primer composition.

  Viscoelastic dampers are used in various fields. For example, it is used for building skeleton structure forming materials in the building field for the purpose of absorbing displacement and vibration due to wind, earthquake, etc., and electronic parts such as computer disk drives for the purpose of preventing damage or malfunction due to vibration It is used for.

  When installed as a viscoelastic damper, viscoelastic dampers of various thicknesses are required for the desired damper performance or damper shape. In order to produce viscoelastic dampers with various thicknesses, it is possible to efficiently produce viscoelastic dampers with a desired thickness by creating a thinner viscoelastic body layer and laminating them. Useful to do.

  However, if the adhesion between the viscoelastic layers is poor, peeling between layers occurs due to repeated vibration and displacement, and the performance as a viscoelastic damper cannot be exhibited. Therefore, it is preferable to provide a primer layer between the viscoelastic layers to increase the adhesion between the viscoelastic layers.

  As a material for the viscoelastic layer, it is desirable to exhibit stable vibration damping performance in a wide range of frequencies and operating temperatures, and rubber-based, silicone-based, acrylic-based resins, etc. have been proposed. Among these, acrylic resins are generally excellent in weather resistance and heat resistance, so they are suitable for viscoelastic dampers used for a long period of time. Primers that increase the adhesion between various acrylic viscoelastic layers are available. Was needed.

  The inventors of the present invention provide a mixture containing a (meth) acrylic monomer having an alkyl group having 14 to 22 carbon atoms as an acrylic viscoelastic body having a low temperature dependence and exhibiting stable vibration damping performance over a wide range of operating temperatures. An acrylic viscoelastic body obtained by polymerizing acrylonitrile has been developed (Patent Document 1), but such an acrylic viscoelastic body layer has low adhesion to each other, and a primer that increases the adhesion between the layers is desired. It was.

  On the other hand, although acrylic pressure-sensitive adhesives containing nitrogen-containing monomers are described (Patent Documents 2 and 3), these pressure-sensitive adhesives are intended to be used for plasticized vinyl resins by having high plasticizer resistance. . As disclosed in Patent Documents 4 and 5, there are some that exhibit excellent adhesion performance to acid rain resistant automotive paints.

  Further, as an adhesive composition exhibiting excellent bond strength to a polycarbonate substrate at a high relative humidity and a high temperature, an acrylic acid having an N-vinyl-containing monomer and an alkyl group containing 4 to 20 carbon atoms is used. Adhesive polymers containing reactive organisms with ester monomers have been described (Patent Document 6).

  In addition, it is described that a pressure-sensitive adhesive containing a nitrogen-containing vinyl monomer is used for a stretch release tape that maintains excellent adhesion to a plasticized vinyl substrate having an uneven surface (Patent Document 7).

  Also, use a pressure-sensitive adhesive composition containing a nitrogen-containing (meth) acrylic copolymer in a re-peelable pressure-sensitive adhesive tape that does not cause adhesive residue on the adherend or cause damage to the adherend. Is described (Patent Document 8).

Japanese Patent Application No. 2008-98445 JP-A-2-018486 Japanese Patent Laid-Open No. 8-31114 JP 2000-096012 A JP-A-7-003236 Japanese translation of PCT publication No. 2003-501296 US Patent Application Publication No. 2008/0135159 JP 2005-194525 A

  An object of this invention is to provide the primer composition for viscoelastic dampers which improves the adhesiveness between various acrylic viscoelastic body layers. Another object of the present invention is to provide a viscoelastic damper that includes the above-described primer composition to enhance adhesion between viscoelastic layers and prevent peeling between layers against repeated vibrations.

  That is, the present invention has at least one nitrogen-containing monomer selected from the group consisting of dialkyl (meth) acrylamide, dialkylaminoalkyl (meth) acrylate, and N-vinylimidazole, and an alkyl group having 4 to 22 carbon atoms. A primer composition for a viscoelastic damper obtained by polymerizing a monomer mixture containing a (meth) acrylic monomer (C4-22 monomer), wherein the nitrogen-containing monomer is another monomer mixture containing the C4-22 monomer. The primer composition for a viscoelastic damper contained in an amount of 5.0 to 40 parts by mass with respect to 100 parts by mass is provided.

  Furthermore, this invention provides the viscoelastic damper which has arrange | positioned the said primer composition for viscoelastic dampers between the layers of a viscoelastic body layer.

  The primer composition for a viscoelastic damper of the present invention can enhance the adhesion between various acrylic viscoelastic layers. Preferably, a polymer obtained by polymerizing a mixture containing a (meth) acrylic monomer having an alkyl group having 14 to 22 carbon atoms, a block copolymer containing a polyolefin block and an aromatic vinyl monomer block, a polyolefin And an acrylic viscoelastic body containing a resin selected from the group consisting of these, and can improve the adhesion between the layers.

  Furthermore, the viscoelastic damper of the present invention increases the adhesion between the viscoelastic body layers by including the above-mentioned primer composition, prevents peeling between layers against repeated vibrations, and improves the performance as a viscoelastic damper. it can.

It is the figure which showed typically sectional drawing of the viscoelastic damper of this invention. It is the figure which showed typically sectional drawing of the measurement sample of T peel strength. It is the figure which showed typically sectional drawing of the measurement sample of T peel strength. It is the figure which showed typically the cross-sectional view of the storage elastic modulus G1 ', G2' measurement sample before and behind repeated vibration. It is the figure which showed typically the cross-sectional view of the storage elastic modulus G1 ', G2' measurement sample before and behind repeated vibration. 10 is a stress-strain curve of Example 13. It is a stress-strain curve of Example 14. 10 is a stress-strain curve of Comparative Example 7. 10 is a stress-strain curve of Comparative Example 8.

  The primer composition for a viscoelastic damper of the present invention comprises at least one nitrogen-containing monomer selected from the group consisting of dialkyl (meth) acrylamide, dialkylaminoalkyl (meth) acrylate, and N-vinylimidazole (Vim), and carbon. It is obtained by polymerizing a monomer mixture containing a (meth) acrylic monomer (C4-22 monomer) having 4 to 22 alkyl groups.

  The dialkyl (meth) acrylamide is selected from the group consisting of N, N-dimethylacrylamide (DMAA), N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N, N-diethylmethacrylamide, and mixtures thereof. However, it is not limited to these.

  The dialkylaminoalkyl (meth) acrylate is selected from the group consisting of N, N-dimethylaminoethyl methacrylate, N, N-dimethylaminopropyl methacrylate, N, N-dimethylaminoethyl acrylate, and mixtures thereof. Although it is mentioned, it is not limited to these.

  Of the nitrogen-containing monomers, Vim is preferably used from the viewpoint of increasing the adhesion between the viscoelastic layers.

  The nitrogen-containing monomer is preferably added in an amount of 5.0 parts by mass or more with respect to 100 parts by mass of another monomer mixture containing a C4-22 monomer. If the amount is less than 5.0 parts by mass, sufficient adhesiveness cannot be obtained.

C4-22 monomer is generally the formula CH ^₂ = ^CR 1 COOR ₂ in (in the formula, R ¹ is a hydrogen or a methyl group, R ² is an alkyl group.) Represented by. Examples of the C4-22 monomer include n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, isobutyl (meth) acrylate, 2-methylbutyl (meth) acrylate, and n-octyl (meth) ) Acrylate, isononyl (meth) acrylate, isodecyl (meth) acrylate, isostearyl (meth) acrylate, cetyl (meth) acrylate, n-stearyl (meth) acrylate, n-behenyl (meth) acrylate, isomyristyl (meth) acrylate Isopalmityl (meth) acrylate and the like can be used. In the present specification, “(meth) acryl” means acryl or methacryl.

  The monomer mixture to be polymerized may contain monomers other than the nitrogen-containing monomer and the C4-22 monomer described above. For example, acidic monomers including unsaturated carboxylic acids, unsaturated sulfonic acids, and unsaturated phosphoric acids may be included. Examples of acidic monomers include those selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, fumaric acid, crotonic acid, maleic acid, sulfoethyl methacrylate, and the like, and mixtures thereof. It is not limited.

  Examples of the method for polymerizing the monomer mixture include known polymerization methods such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization.

  In particular, in order to obtain a primer layer having a thickness of 0.05 mm or more, it is preferable to use an environment-friendly solvent-free process and bulk polymerization by photopolymerization excellent in productivity. In this case, a photopolymerization initiator is added to the monomer mixture. It is made to contain and superpose | polymerize by irradiating light. In the following, the polymerization method will be described taking photopolymerization with ultraviolet rays as an example.

  In a suitable reaction vessel, a monomer mixture containing a C4-22 monomer and a nitrogen-containing monomer, and a photopolymerization initiator are added, and a cross-linking agent or other additive is added as necessary to add an appropriate amount of ultraviolet light, etc. A polymerization reaction is performed by light irradiation to obtain a primer composition. The reaction is usually carried out in an inert atmosphere such as a nitrogen atmosphere.

  As a photopolymerization initiator, for example, benzoin such as benzoin, benzoin methyl ether, benzoin isopropyl ether, and α-acryl benzoin, 2,2-dimethoxy-1,2-diphenylethane-1-one (manufactured by Ciba Specialty Chemicals) Irgacure 651), 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure 184 manufactured by Ciba Specialty Chemicals), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Darocure 1173 manufactured by Ciba Specialty Chemicals) ), 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one (Irgacure 2959, manufactured by Ciba Specialty Chemicals), 2-methyl-1 [4 -(Methylthio) phenyl] -2-mo Ruforinopropan-1-one (Irgacure 907 manufactured by Ciba Specialty Chemicals), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (Irgacure 369 manufactured by Ciba Specialty Chemicals) Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (Irgacure 819, manufactured by Ciba Specialty Chemicals) 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (produced by Ciba Specialty Chemicals) (Trademark) TPO), 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propyl) -benzyl] -phenyl} -2-methyl-propan-1-one (Ciba Specialty Chemicals) Irgacure 127), 2-dimethylamino 2- (4-methyl-benzyl) - 1 - (4-morpholin-4-yl-phenyl) - - butan-1-one (Ciba Specialty Chemicals Inc. Irgacure 379) can indicate the like.

  A photoinitiator is mix | blended by 0.01-5.0 mass parts with respect to 100 mass parts of monomer mixtures.

  An ultraviolet lamp is usually used for light irradiation. As the ultraviolet lamp, a lamp having an emission spectrum distribution at a light wavelength of 300 to 400 nm is used. Examples thereof include a chemical lamp, a black light lamp (manufactured by Toshiba Denshi Co., Ltd.), a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, and a metal halide lamp. And a microwave-excited mercury lamp.

  Light irradiation may be performed at one time, but may be performed in two or more stages. For example, a mixture containing a polymerization initiator is irradiated with light and partially reacted to obtain a polymerizable prepolymer syrup having an appropriate viscosity. Thereafter, additional monomer is placed in the syrup, and this mixture is introduced between two exfoliated substrates such as polyethylene terephthalate (PET), followed by light irradiation to obtain the final primer composition. You can also.

  A crosslinking agent can also be used in order to increase the adhesive strength and thermal characteristics of the primer composition obtained. As the crosslinking agent, a crosslinking monomer such as a polyvalent acrylate can be used. As polyvalent acrylate usable as a crosslinking agent, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate , Polyacrylates such as dipentaerythritol hexaacrylate, polyether acrylates such as ethylene glycol diacrylate, diethylene glycol diacrylate, propylene glycol diacrylate, dipropylene glycol, acrylic acid adducts of 1,6-hexanediol diglycidyl ether, etc. Epoxy polyacrylate, polyester polyacrylate, polyurethane polyacrylate, etc. It is.

  The primer composition may contain a tackifier in order to further improve the adhesion with the viscoelastic damper layer. Examples of such tackifiers include rosin resins, modified rosin resins (hydrogenated rosin resins, disproportionated rosin resins, polymerized rosin resins, etc.), terpene resins, terpene phenol resins, aromatic modified terpene resins, There are C 5 and C 9 petroleum resins, coumarone resins and the like. Of these, a saturated hydrocarbon resin having good weather resistance can be preferably used.

  As long as the effect of the present invention is not impaired, one or more of other additives such as an antioxidant, an ultraviolet absorber, a light stabilizer, a plasticizer, a lubricant, an antistatic agent, a flame retardant, and a filler are added. It may be added to the primer composition.

  When arrange | positioning the primer composition of this invention as a primer layer between viscoelastic body layers, the thickness of a primer layer is 0.01-0.30 mm, Preferably it can be 0.05-0.30 mm.

  An acrylic viscoelastic body is mentioned as a viscoelastic body by which a primer composition is arrange | positioned. Polymer, polyolefin, polyolefin block and aromatic vinyl monomer block obtained by polymerizing a mixture containing a (meth) acrylic monomer having an alkyl group having 14 to 22 carbon atoms (hereinafter referred to as C14-22 monomer) The primer composition of the present invention can also be used in the case where a resin selected from the group consisting of a block copolymer containing the above (hereinafter referred to as a block copolymer) and a mixture thereof is used as the viscoelastic damper.

  Examples of the C14-22 monomer include isostearyl (meth) acrylate, cetyl (meth) acrylate, n-stearyl (meth) acrylate, n-behenyl (meth) acrylate, isomyristyl (meth) acrylate, and isopalmityl (meth) acrylate. Etc. can be used. Depending on the purpose, one or more C14-22 monomers can be used to obtain the desired properties.

  Examples of polyolefins include polyethylene, polybutene, polypropylene, polyisobutylene, poly α-olefin, ethylene / propylene copolymer, ethylene / α-olefin copolymer, propylene / α-olefin copolymer, hydrogenated polybutadiene, and the like. Can be mentioned. These may be used alone or in combination of two or more.

  The block copolymer includes a block made of polyolefin and a block made of aromatic vinyl monomer. Examples of the aromatic vinyl monomer include styrene, p-methylstyrene, α-methylstyrene, and indene. These may be used alone or in combination of two or more. Examples of the block copolymer include a styrene-ethylene-propylene-styrene block copolymer, a styrene-ethylene-propylene block copolymer, and a styrene-ethylene-butylene-styrene block copolymer.

  A saturated polyolefin may be used as the polyolefin. The saturated polyolefin is a polyolefin having substantially no carbon double bond or triple bond, and more specifically, a polyolefin in which 90% or more of carbon-carbon bonds contained in the saturated polyolefin are single bonds. is there.

  The blending ratio of the saturated polyolefin and / or the block copolymer can be 2 to 40 parts by mass with respect to 100 parts by mass of the (meth) acrylic monomer mixture. If it is less than 2 parts by mass, it becomes difficult to obtain a viscoelastic damper having a small temperature dependency. If it exceeds 40 parts by mass, the weather resistance and heat resistance are poor, and the reliability of long-term use becomes low. This is because the adhesion to the kimono also deteriorates.

  The weight average molecular weight of the saturated polyolefin and the block copolymer may be in the range of 10,000 to 2,000,000. This is because when the molecular weight is decreased, the elastic modulus tends to decrease, the heat resistance is poor, and the reliability of long-term use may be lowered.

  Examples of the method for polymerizing a (meth) acrylic monomer mixture containing a C14-22 monomer include known polymerization methods such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization. After polymerizing a (meth) acrylic monomer mixture containing a C14-22 monomer, a viscoelastic damper can be obtained by adding a polyolefin and / or block copolymer. In the presence, a (meth) acrylic monomer mixture containing C14-22 monomer can also be polymerized.

  In order to obtain a thick viscoelastic body, it is preferable to use photopolymerization. In this case, the polymerization is carried out by containing a photopolymerization initiator and irradiating light. Moreover, although light irradiation may be performed at once, it may be performed in two or more stages. For example, a mixture containing a polymerization initiator is irradiated with light and partially reacted to obtain a polymerizable prepolymer syrup having an appropriate viscosity. Then, an additional monomer is put in a syrup, and this mixture is introduced between two exfoliated polyethylene terephthalate (PET) base materials and then irradiated with light to form a viscoelastic damper.

  The viscoelastic body thus obtained is a viscoelastic body having a small ratio of shear storage modulus at 0 ° C. and 40 ° C. (G′0 / G′40) and less temperature dependency. In order to further reduce the temperature dependence, it is preferable to use a viscoelastic body whose G′0 / G′40 value does not exceed 15.0.

A viscoelastic body having a shear storage modulus G ′ of 1.5 × 10 ^{4 to} 5.0 × 10 ⁶ Pascals (Pa) in the range of 0 ° C. to 40 ° C. can also be used. In order to further increase the cohesive force, it is preferable to use a viscoelastic body having G ′ of 1.5 × 10 ⁴ Pa or more. In order to further improve the adhesion to the adherend, G ′ is 5 It is preferable to use a viscoelastic body having a viscosity of 0.0 × 10 ⁶ Pa or less.

  In order to make the vibration absorption higher, a viscoelastic body having a loss tangent tan δ of 0.5 or more can be used.

Method for Measuring Shear Storage Elastic Modulus G ′ and Loss Tangent Tan δ Using Rheometric Scientific Advanced System Expansion System (ARES), frequencies of 0.1, 0.3, 1.0, 3.0 and 10. At 0 Hz, the shear storage modulus G ′ and loss tangent tan δ at temperatures of 0, 10, 20, 30, and 40 ° C. are measured in shear mode.

  The thickness of the viscoelastic body obtained by using photopolymerization is usually 0.5 to 2.0 mm, and in order to obtain the desired damper performance and shape, the viscoelastic body is layered to obtain a desired thickness. A viscoelastic damper with a thickness is produced.

  When a viscoelastic damper is produced by laminating viscoelastic layers, a primer layer composed of the primer composition of the present invention is placed between the viscoelastic layers, and pressure or temperature is applied to apply the viscoelasticity of the present invention. A damper can be obtained. As shown in FIG. 1, the viscoelastic damper of the present invention is a multilayer structure in which at least two viscoelastic damper layers and a primer layer are laminated therebetween.

  By using the primer composition of the present invention, adhesion between viscoelastic layers can be enhanced. As for the adhesiveness between layers, the value measured by T peel strength is preferably 27 N / 25 mm or more, and more preferably 30 N / 25 mm or more.

Method for measuring T peel strength T peel strength can also be measured by the following method.
An anodized aluminum film (manufactured by 3M), a viscoelastic body layer, a primer layer, a viscoelastic body layer, and an anodized aluminum film are laminated in this order and laminated as shown in FIG. The sample without the primer layer is laminated as shown in FIG. The peel strength when the ends of the two anodized aluminum films are pulled and peeled is measured under the following conditions.
Measuring device: TENSILON RTC-1325 manufactured by ORIENTEC
Measurement temperature: 25 ° C
Peeling speed: 50 mm / min

  By using the primer composition of this invention, the reliability with respect to the repeated vibration of a viscoelastic damper can be improved. By giving shear deformation of 50%, 100%, 200%, 300%, 350%, 400%, 450%, 500% to the viscoelastic damper, repeated vibration is given, and storage elastic modulus G1 ′ before and after repeated vibration, In G2 ′, the retention rate (G2 ′ / G1 ′) is preferably 70% or more, and more preferably 80% or more.

Method for Measuring Storage Elastic Modulus G1 ′, G2 ′ Before and After Repeated Vibration The storage elastic modulus G1 ′, G2 ′ before and after repeated vibration can also be measured by the following method.
Four viscoelastic material layers of 50 mm × 50 mm × 1.2 mm and three primer layers are laminated as shown in FIG. 4 and further adhered between three steel plates to prepare a measurement sample. The measurement sample is subjected to shear deformation, and the dynamic viscoelastic property of the storage elastic modulus G1 ′ (N / cm ² ) is obtained under the following conditions.
Test apparatus: MTS uniaxial vibrator MTS 810 (maximum displacement 250 mm, maximum speed 75 kine, maximum load 25 kN)
Measurement temperature: 20 ° C
Measurement frequency: 1.0Hz
Shear strain: 50%, 100%, 200%, 300%, 350%, 400%, 450%, 500%
Further, after measuring the storage elastic modulus G1 ′ at each shear strain, the storage elastic modulus G2 ′ after repeated vibration is again measured in the same manner as described above under the conditions of a measurement temperature of 20 ° C., a frequency of 1.0 Hz, and a shear strain of 50%. taking measurement.

In the present specification, the following abbreviations may be used.
ISA: Isostearyl acrylate (Shin Nakamura Chemical Co., Ltd. NK Ester ISA)
HEDA16: Isopalmityl acrylate (HEDA16 manufactured by Toho Chemical Industry Co., Ltd.)
2-EHA: 2-ethylhexyl acrylate (AEH manufactured by Toa Gosei Co., Ltd.)
IOA: Isooctyl acrylate (manufactured by 3M)
BA: n-butyl acrylate (Mitsubishi Chemical Corporation)
AA: Acrylic acid (manufactured by Toa Gosei Co., Ltd.)
Vim: N-vinylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.)
DMAA: N, N-dimethylacrylamide (manufactured by Kojin Co., Ltd.)
DMAEA: N, N-dimethylaminoethyl acrylate (manufactured by Kojin Co., Ltd.)
NVP: N-vinylpyrrolidone (Wako Pure Chemical Industries, Ltd.)
V-CAP: N-Vinylcaprolactam (V-CAP / RC made by ASP Japan)
HDDA: 1,6-hexanediol diacrylate (Kyoeisha Chemical Co., Ltd. Light Acrylate ^TM 1,6HX-A)
Oppanol ^™ B-100: Polyisobutylene (manufactured by BASF Opanol ^™ B-100, weight average molecular weight 1,100,000)
Septon ^TM 1001: styrene - ethylene - propylene block copolymer (manufactured by Kuraray Co. Septon ^TM 1001,35wt% styrene content, weight average molecular weight 190,000)
RR6108: (Regalrez ^™ 6108, Eastman Chemical Co., Ltd., partially hydrogenated hydrocarbon tackifier, softening point 108 ° C., weight average molecular weight 1,400)
Darocur ^™ TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (Darocur ^™ TPO manufactured by Ciba Specialty Chemicals)
Irgacure ^™ 651: 2,2-dimethoxy-1,2-diphenylethane-1-one (Irgacure ^™ 651 manufactured by Ciba Specialty Chemicals)

  EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated in more detail, this invention is not limited to these.

Production of viscoelastic body Viscoelastic body (VEM-1)
92 parts by weight of ISA, 8 parts by weight of AA, 5.5 parts by weight of Oppanol ^™ B-100, 0.1 part by weight of HDDA, and 0.3 parts by weight of Darocur ^™ TPO as a photopolymerization initiator were mixed. The resulting mixed solution was sandwiched between two exfoliated PET films with a thickness of 50 μm so as to have a film thickness of 1.2 mm, and irradiated with an ultraviolet ray with a cumulative amount of 3000 mJ / cm ^{2 with} a fluorescent black bulb (Sylvania ™ F20T12B). Then, viscoelastic body layer VEM-1 was produced by reaction curing.

Viscoelastic body (VEM-2)
Similarly to VEM-1, 92 parts by weight of HEDA16, 8 parts by weight of AA, 8 parts by weight of Septon ^™ 1001, 0.1 part by weight of HDDA, 0.3 parts by weight of Darocur ^™ TPO as a photopolymerization initiator Mixed. The resulting mixed solution was sandwiched between two peeled PET films with a thickness of 50 μm so as to have a film thickness of 1.2 mm, and reacted and cured by irradiating 3000 mJ / cm ² of UV light with a Sylvania ^™ F20T12B, and viscoelastic. Body layer VEM-2 was created.

  Table 1 shows the measurement results of the shear storage modulus G ′ and loss tangent tan δ of these viscoelastic single layers.

Example 1
100 parts by mass of 2-EHA, 7.5 parts by mass of Vim, 0.11 parts by mass of HDDA, and 0.16 parts by weight of Irgacure ^™ 651 as a photopolymerization initiator were mixed. The resulting mixed solution was sandwiched between two exfoliated PET films with a thickness of 50 μm so as to have a film thickness of 0.1 mm, and reacted and cured by irradiating an ultraviolet ray with a cumulative amount of 3000 mJ / cm ² with Sylvania ^™ F20T12B. A primer layer of Example 1 of 0.1 mm was produced.

  The primer layer was laminated with each of VEM-1 and VEM-2 as shown in FIG. 2, and the T peel strength was measured. Peeling of the interface between the anodized aluminum and the viscoelastic material layer was not observed, and peeling was caused by the interface between the viscoelastic material layer and the primer layer or cohesive failure. The results are shown in Table 2.

Example 2 to Example 8
In the same manner as in Example 1, a mixed solution was prepared with the formulation shown in Table 2, and reacted and cured with ultraviolet rays to prepare a primer layer. As a result of evaluating the adhesiveness of the primer layer to VEM-1 and VEM-2 with T peel strength as in Example 1, peeling of the interface between the anodized aluminum and the viscoelastic body layer was observed in all the primer layers. However, it peeled off at the interface between the viscoelastic material layer and the primer layer or cohesive failure. The results are shown in Table 2.

Comparative Example 1
Without using a primer layer, VEM-1 and VEM-2 were laminated as shown in FIG. 3 to evaluate the self-adhesiveness of the viscoelastic body. VEM-1 has a low peel strength of 25 N / 25 mm, and VEM-2 has a low peel strength of 11 N / 25 mm.

Comparative Examples 2-5
In the same manner as in Example 1, a mixed solution was prepared with the formulation shown in Table 2, and reacted and cured with ultraviolet rays to prepare a primer layer. Table 2 shows the results of evaluating the adhesion of the primer layer to VEM-1 and VEM-2 with T peel strength. In all the formulations, peeling occurred at the interface between the viscoelastic material layer and the primer layer.

Examples 9-12, Comparative Example 6
In the same manner as in Example 1, a mixed solution was prepared with the formulation shown in Table 3, and reacted and cured with ultraviolet rays to prepare a primer layer. The adhesiveness of the resulting primer layer to the VEM-1 layer was evaluated by T peel strength. The results are shown in Table 3. Except for the blending of Comparative Example 6, sufficient strong adhesion of 30 N / 25 mm or more was exhibited.

Example 13
The case where the result of the present invention was used as a vibration control device for a building structure was simulated, and dynamic viscoelasticity measurement was performed in a situation close to its practical form.
Four VEM-1 layers of 50 mm × 50 mm × 1.2 mm size and three primer layers used in Example 9 were laminated as shown in FIG. 4, and further three steel plates (60 mm × 150 mm size, the center being 12 mm thick) And the outside is 9 mm thick). Shear deformation was applied, and storage elastic modulus (storage elastic modulus G1 ′ before repeated vibration) (N / cm ² ) and loss factor (tan δ1) were determined under the following conditions.
Test apparatus: MTS uniaxial vibrator MTS 810 (maximum displacement 250 mm, maximum speed 75 kine, maximum load 25 kN)
Measurement temperature: 20 ° C
Measurement frequency: 1.0Hz
Shear strain: 50%, 100%, 200%, 300%, 350%, 400%, 450%, 500%
Further, after measuring the storage elastic modulus G1 ′ at each shear strain, the storage elastic modulus G2 ′ after repeated vibration is again measured in the same manner as described above under the conditions of a measurement temperature of 20 ° C., a frequency of 1.0 Hz, and a shear strain of 50%. It was measured. Table 4 shows the storage elastic modulus G1 ′ and loss factor tan δ1 at each shear strain, and FIG. 6 shows the stress-strain curve.

  From the results, it was confirmed that the stress-strain curve of the viscoelastic body showed an ellipse and absorbed energy, which was confirmed to be useful as a viscoelastic damper.

  Furthermore, it was found that the storage elastic modulus retention rate was 80% or more even for a shear strain of 500%, and the primer layer suppressed breakage due to peeling and exhibited sufficient reliability against repeated vibration.

Example 14
In the same manner as in Example 13, the dynamic viscoelasticity measurement was performed using the VEM-2 layer and the primer layer used in Example 3. FIG. 7 shows a stress-strain curve, and Table 4 shows the storage elastic modulus and loss factor for each shear strain. From the results, it was confirmed that the stress-strain curve of the viscoelastic body showed an ellipse and absorbed energy, which was confirmed to be useful as a viscoelastic damper. Furthermore, it was found that the storage elastic modulus retention rate was 80% or more even for a shear strain of 500%, the primer layer suppressed breakage due to peeling, and exhibited sufficient reliability against repeated vibration.

Comparative Example 7
Except not using a primer layer, it carried out similarly to Example 13, and laminated | stacked only four VEM-1 layers of 50 mm x 50 mm x 1.2 mm size as shown in FIG. 5, and it was made to adhere between three steel plates. . The dynamic viscoelasticity measurement was performed in the same manner as in Example 13. FIG. 8 shows a stress-strain curve, and Table 5 shows the storage elastic modulus and loss factor for each shear strain.

  Breaking due to peeling was confirmed when the shear strain exceeded 450%, and the stress-strain curve shape was significantly collapsed due to the shear strain of 500%, and the storage modulus decreased significantly. From this result, it was found that the reliability was inferior to repeated vibration.

Comparative Example 8
Except not using a primer layer, it carried out similarly to Example 13, and laminated | stacked only the VEM-2 layer of 50 mm x 50 mm x 1.2 mm size as shown in FIG. 5, and it was made to adhere between three steel plates. . The dynamic viscoelasticity measurement was performed in the same manner as in Example 13. FIG. 9 shows a stress-strain curve, and Table 5 shows the storage elastic modulus and loss factor for each shear strain.

  Breaking due to peeling was confirmed by a shear strain exceeding 300%, the stress-strain curve shape was greatly broken, the storage elastic modulus was significantly lowered, and it was found that the reliability was inferior to repeated vibration.

10 Viscoelastic damper 20 Primer layer 30 Viscoelastic body layer 32 Viscoelastic body layer (VEM-1 or VEM-2)
40 T peel strength measurement sample 1
42 T peel strength measurement sample 2
50 Anodized aluminum film 60 Storage elastic modulus G1 ′, G2 ′ measurement sample 1 before and after repeated vibration
62 Storage elastic modulus G1 ′, G2 ′ measurement sample 2 before and after repeated vibration
70 steel plate

Claims (5)

(Meth) acrylic monomer having at least one nitrogen-containing monomer selected from the group consisting of dialkyl (meth) acrylamide, dialkylaminoalkyl (meth) acrylate, and N-vinylimidazole, and an alkyl group having 4 to 22 carbon atoms A primer composition for a viscoelastic damper that is obtained by polymerizing a monomer mixture containing (C4-22 monomer) and is suitable for application between acrylic viscoelastic layers of an acrylic viscoelastic layer including an acrylic viscoelastic layer. There,
The nitrogen-containing monomer is a primer composition for a viscoelastic damper that is contained in an amount of 5.0 to 40 parts by mass with respect to 100 parts by mass of another monomer mixture containing the C4-22 monomer.   The primer composition for a viscoelastic damper according to claim 1, wherein the nitrogen-containing monomer is N-vinylimidazole.   The primer composition for a viscoelastic damper according to claim 1 or 2, further comprising a tackifier. A viscoelastic damper including an acrylic viscoelastic layer, wherein the acrylic viscoelastic layer is obtained by polymerizing a mixture containing a (meth) acrylic monomer having an alkyl group having 14 to 22 carbon atoms. containing polymers, viscoelastic dampers arranged between the layers of the viscoelastic layer viscoelastic damper primer composition according to any one of claims 1 to 3. The viscoelastic damper according to claim 4 , wherein the primer composition for the viscoelastic damper has a thickness of 0.01 to 0.30 mm.

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