JPH03294329A - Resin composition - Google Patents

Abstract

PURPOSE:To provide a composition containing an epoxy resin, a specific acrylonitrile-butadiene copolymer, an acryloyl-containing (meth)acrylate, an organic peroxide and an epoxy resin hardener, having excellent vibration- damping property and heat-resistance and useful as an adhesive. CONSTITUTION:The objective composition contains (A) an epoxy resin (e.g. epoxy resin modified with acrylonitrile-butadiene or urethane-modified epoxy resin), (B) an acrylonitrile-butadiene copolymer (preferably having a molecular weight of 1,000-7,000) having polar groups (e.g. carboxyl group or amino group) on both terminals, (C) a (meth)acrylate having acryloyl group, (D) an organic peroxide (e.g. ketone peroxide) and (E) an epoxy resin hardener (e.g. dicyandiamide).

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention has excellent vibration damping properties over a wide temperature range from extremely low temperatures to high temperatures, and has excellent heat resistance properties, and is suitable for use as a structural adhesive. First, it relates to a novel resin composition that can be effectively used for a variety of purposes.

[Conventional technology]

Structural adhesives are used when assembling structures such as aircraft and automobiles, and when joining steel and aluminum alloys with rivets, etc.
It is used in place of traditional joining methods such as bolts and welding. It is also used as a weld bonding method in combination with conventional bonding methods.

On the other hand, in recent years, noise and vibration have become a problem (becoming a social problem), and measures to improve the environment are strongly desired. However, the structural strength of the polymer material used to provide the III vibration performance is low, and due to processing, it is difficult to follow the wAvi and restraint layers. , Adhesive strength (poor, improvement is desired).

Conventional structural adhesives have vibration damping properties in a narrow temperature range, but lack damping performance over the entire temperature range of the usage environment. At present, only vibration-damping adhesives are selected and used, and social demands are not met because there is no vibration-damping structural adhesive suitable for use in a wide range of environmental temperatures.

As is clear from the above description, there is a strong desire for structural adhesives and resin compositions that exhibit excellent vibration damping performance and adhesive properties over a particularly wide temperature range.

As mentioned above, there are structural adhesives as adhesives with high adhesive properties.They are highly reliable adhesives with little deterioration in adhesive properties even under large loads for long periods of time, and nitrile-phenolic, nitrile-epoxy , modified epoxy,
The main component is a polymer such as modified acrylic or polyimide, but because it is a highly rigid material, it cannot exhibit vibration damping properties over a wide temperature range. In order to improve vibration damping properties, a resin composition must have high vibration energy absorption.

A typical epoxy resin composition is in a glass state at room temperature, and therefore has extremely high shear adhesive strength but extremely low peel adhesive strength. One way to increase energy absorption in such systems is to add plasticizers or flexibilizers. Although it improves, shear adhesive strength and heat resistance decrease.

Another method is to add liquid rubber, etc., such as carboxyl group-terminated acrylonitrile-butadiene copolymer (cTBN).
Although there are many reports on the modification of epoxy resins with This phenomenon can be explained by the intermolecular compatibilization of the art dealer molecules.

Ordinary polymer alloys aim to realize various morphologies and physical properties based on them by utilizing or limiting the compatibility between different types of polymers, but as mentioned above, they have no effect on vibration damping properties. I can't see it. Also,
For example, even if a polymer alloy of different types of polymers with poor compatibility is employed, only a resin composition having two so-called vibration damping property peaks can be obtained. In addition, this composition is inherently poor in compatibility and has extremely poor uniform dispersibility and storage stability, making it impractical.

Therefore, the IPN (Interpenetrating Network Polymer) method has been considered, which results in an increase in the elastic modulus and a rise in the glass transition temperature compared to ordinary polymer alloys.

The IPN method has been reported for polyacrylate-polystyrene, polyacrylate-urethane, polybutadiene-polyacrylonitrile butadiene, and urethane-urea systems, but no practical examples have been found for adhesives and resin compositions. Further, even when the present inventors evaluated the damping characteristics, the temperature dependence was not improved.

On the other hand, as examples of compositions, adhesive compositions are proposed in JP-A-59-159866 and JP-A-63-186786. Although these adhesive compositions have excellent oil surface adhesion, their vibration damping properties are not sufficient.

[Problem to be solved by the invention]

The above-described IPN method is considered to be free from the constraints of compatibility between different polymer components and to obtain a new degree of freedom.

As a result of extensive research, the present inventors have succeeded in developing a completely new resin composition that has low temperature dependence in vibration damping properties and excellent heat resistance properties.

The present invention exhibits excellent vibration damping properties and adhesive performance over a wide temperature range from extremely low temperatures to high temperatures, and also has excellent heat resistance properties, and can be effectively used in a variety of applications including structural adhesives. The purpose is to provide a new resin composition.

[Means to solve the problem]

In order to solve the above problems, the resin composition of the present invention includes: (a) an epoxy resin; (b) an acrylonitrile-butadiene copolymer having polar groups at both ends; (c) a resin composition having one or more acryloyl groups; (meth)acrylate; (d) an organic peroxide; and (e) an epoxy resin curing agent.

The epoxy resin (a) of the present invention has an average of -
Epoxy compounds having more than one epoxy group can be used. Specific examples include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol A
D-type epoxy resin, phenol novolac type epoxy resin, Talesol novolank type epoxy resin, aliphatic glycidyl ester type epoxy resin, aliphatic glycidyl ether type epoxy resin, aromatic glycidyl ester type epoxy resin, aromatic glycidyl ether type epoxy resin ,
Multifunctional epoxy resins, various halogenated epoxy resins,
Examples include dimer acid-modified epoxy resins, oil-modified epoxy resins, cycloaliphatic epoxy resins, glycidylamine-type epoxy resins, heterocyclic epoxy resins, and hydantoin-type epoxy resins.

Furthermore, as the epoxy resin (a) of the present invention, an acrylonitrile-butadiene-modified epoxy resin (hereinafter referred to as rubber-modified epoxy resin) can be used. for example,
Bisphenol A type epoxy resin or bisphenol F
A rubber-modified epoxy resin obtained by copolymerizing a type epoxy resin and a carboxyl group-terminated acrylonitrile-butadiene copolymer or an acrylonitrile-butadiene copolymer can be used. As a typical product of this type,
Examples include Adeka Resin EP-4023 (manufactured by Asahi Denka Kogyo ■), Adeka Resin EP-4024 (manufactured by Asahi Denka Kogyo ■), Adeka Resin EP-4026 (manufactured by Asahi Denka Kogyo ■), and the like.

Furthermore, as the epoxy resin (a) of the present invention, a urethane-modified epoxy resin can be used. For example, a liquid urethane-modified epoxy resin whose skeleton is a copolymer of bisphenol A type epoxy, a polyether polyol or a polyester polyol, and a urethane prepolymer containing terminal isocyanate groups obtained from an organic polyisocyanate can be used. Typical products of this type include Adekal Resin EPU-6 (manufactured by Asahi Denka Kogyo), Adekal Resin EPU-7A (manufactured by Asahi Denka Kogyo), Adekal Resin EPU-73 (manufactured by Asahi Denka Kogyo), and Adekal Resin EP.
LI-79 (manufactured by Asahi Denka Kogyo ■) and the like can be mentioned.

Examples of the acrylonitrile-butadiene copolymer (b) having polar groups at both ends of the present invention include liquid rubbers having the following structural formula and having a molecular weight of about 1,000 to 7,000.

N (In the above formula, X = about 5, Y = about Lm - about 10, R
: A group of functional groups having a polar group such as a carboxyl group, an amino group, a vinyl group, a hydroxyl group, an epoxy group, or a mercapto group at the end. ) Typical products of this type include Hiker TBN1300X8 (B, F, manufactured by Gutdrich), Hiker ATBN1300x16 (B
, F, manufactured by Gutdrich), Hiker ATBN1300
x42 (B, F, manufactured by Gutdrich), Squid-VTB N X 1 300 x 23 (B,
F, Hiker VTBNX 1300 x33 (B.

F, Gutdrich), Hiker HTBN1300X
17 (B, F, manufactured by Gutdrich), Hiker E
Examples include TBNI300x40 (B, F, manufactured by Gutdrich). In particular, those having a vinyl group are preferred.

Examples of the (meth)acrylate having one or more acryloyl groups (c) of the present invention include compounds having the following structural formula. Note that (meth)acrylate is a general term for acrylate and/or methacrylate.

(In the above formula, m + n = 2) H3 I (In the above formula, m + n = 2) (In the above formula, n = 2 to 14) (In the above formula, n = 2 to 14) In addition to the above compounds, Neopentyl glycol di(meth)acrylate, 1.3-butanediol di(meth)acrylate, 1.5-pentadiol di(meth)acrylate, 1.6-hexanethiol di(meth)acrylate, trimethylolpropane triacrylate (meth)acrylate, pentaerythritol tri(meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, allyl glycidyl ether, (meth)acrylic acid adduct of epoxy ester, 2
-Hydroxyethyl (meth)acryloyl phosphate, etc. can be mentioned.

The organic peroxide (d) of the present invention includes known organic peroxides, such as ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate, peroxy Peroxides containing esters, silanes, phthalate esters, etc. can be used.

Furthermore, organic or inorganic acid salts such as iron, cobalt, manganese, and vanadium, or known accelerators such as ascorbic acid and gallic acid may be used in combination.

The resin composition of the present invention is crosslinked by heating, and the organic peroxide and accelerator to be used are selected depending on the heating conditions.

As the epoxy resin curing agent (e) of the present invention, a known epoxy resin curing agent and/or curing accelerator can be used, but since the resin composition of the present invention can be cured by heating. , so-called latent curing agents and/or latent curing accelerators that suit the curing conditions may be selected, such as - dicyandiamide, hydrazide compounds, epoxy resin adducts of imidazole, alkyl urea compounds, etc. One or more of these may be used.

The above-mentioned components are mixed in the following proportions.

10 to 8 parts of component (b) per 100 parts by weight of component (a)
If 0 parts by weight and 5 to 50 parts by weight of component (c) are blended,
The effects of the present invention can be achieved.

Note that the components (d) and (e) may be added in appropriate amounts depending on the blending ratio of the other components.

The resin composition of the present invention is prepared by uniformly mixing the above-mentioned components in a predetermined ratio using a defoaming mixer, a three-roll mill, a whole mill, etc., and if necessary, known additives may be added. , for example, viscosity modifiers, adhesion agents, fillers, pigments, dyes, conductivity agents, leveling agents, dispersants,
Flame retardants (flame retardants), plasticizers, organic solvents, thermoplastic polymer compounds, figuration agents, antifoaming agents, coupling agents, rust preventives,
Flavoring agents and the like may be added.

As the viscosity modifier, known viscosity reducing agents and thixotropic agents used in epoxy resin adhesives may be used. As the viscosity reducing agent, those having a reactive group such as aliphatic diglycidyl ether, triglycidyl ether of trimethylolpropane, and diglycidyl ether of polyoxyalkylene glycol are preferred. As the thixotropic agent, colloidal silica and organic bentonite compounds are preferred.

As the adhesion agent, N-β-(aminoethyl)-r
- Silane-based adhesion promoters such as aminopropyltrimethoxysilane and T-glycidoxypropyltrimethoxysilane, oil adhesion promoters such as 2-hydroxyethyl (meth)acryloyl phosphate, nitrogen-containing (meth)acrylate, and epoxy acrylate. etc. can be used.

As a filler, you can of course use a bulking agent, but
In particular, known fillers that improve vibration damping properties are preferred.

For example, layered compounds (mica, graphite, molybdenum disulfide, boron nitride, etc.), acicular compounds (zonolite, potassium titanate, asbestos, carbon fiber, etc.), granular and platy compounds (ferrite, talc, vermiculite, etc.)
kaolin, clay, etc.). In addition, the filler may be used in combination with a silane camping agent, titanate coupling agent, etc., or may be surface-treated with such agents in advance.The conductivity imparting agent may be used to improve weldability or rust prevention. In order to improve the properties, for example, carbon-based fillers such as acetylene black, Ketchien black, carbon fiber, sintered metal oxide-iron oxide composite ferrite, α-iron oxide particle powder, various metal powders and metals are used. Metal fillers such as fibers, metal compounds, metal composite fillers coated with metal, etc. can be used.

Thermoplastic polymer compounds are used to improve damping performance in a specific temperature range and to improve durability. For example, polybutadiene, polybutadiene with a polar group, acrylonitrile-butadiene copolymer, acrylic rubber, chloroprene rubber, urethane rubber, ethylene-vinyl acetate copolymer, chlorosulfonated polyethylene, ethylene-acrylic acid copolymer, thermoplastic polyurethane , saturated polyester, nylon, polyethylene, polybutene, polyisobutylene, silicone rubber, polysulfide rubber, butyl rubber, urethane-acrylate copolymer, urethane-thiocol copolymer, coal tar, bituminous material, etc. may be used. .

The stabilizer is appropriately selected from known deterioration inhibitors, polymerization inhibitors, etc. in consideration of the formulation, and may be used alone or in combination of two or more. In particular, to improve storage stability, phenols such as hydroquinone, hydroquinone monomethyl ether, 2,6-di-butyl-4-methylphenol alone, amine salts such as N-nitrosophenylhydroxylamine, organic tin It is preferable to use a combination of compounds.

[Effect]

Since the resin composition of the present invention has excellent vibration damping and adhesive properties in the range from extremely low temperatures to high temperatures, it is expected to have extremely good use as a structural adhesive, as well as vibration damping properties. It is effectively used as an adhesive for steel plates, and is also suitable for casting and molding products used in vibrating parts of electrical parts and the like.

〔Effect of the invention〕

As described above, the resin composition of the present invention has excellent vibration damping properties and adhesive properties over the range from extremely low temperatures to surface temperatures in general usage environments, and also has excellent heat resistance properties and durability. etc., and are particularly useful as structural adhesives and vibration-damping steel plate adhesives, and are also suitably used as cast products and molded products, and are effectively used industrially.

〔Example〕

The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples unless the gist thereof is exceeded.

Examples 1 to 7 and Comparative Examples 1 to 3 The compositions shown in Table 1 were prepared by uniformly mixing them using a defoaming mixer.

The results of various tests conducted on these compositions are shown in Table 2 and FIGS. 1 and 2.

Shear adhesive strength and peel adhesive strength tests are conducted according to JIS
It was conducted based on K6850 and JISK6854. However, the test piece material is 5P specified in JISC; 3141.
CC-3D steel plates with a thickness of about 1.6 mm and about 0.8 mm, respectively, were immersed in rust prevention oil (RC-55, manufactured by Idemitsu Petrochemical Co., Ltd.) and left vertically for 24 hours. was used.

The adhesive was cured at 170°C12O min. The tensile speed in the test was 50mm/min and 200ffi, respectively.
The adhesion strength was 20°.
Measurements were made in a C atmosphere and a 100°C atmosphere.

The mechanical loss coefficient was measured using a torsional free damping type viscoelasticity measuring device (R
D-1100AD (manufactured by RESCA).

Preparation of cured product: 1 mm on a Teflon-coated steel plate with a thickness of about 2 mm
Sandwich the liquid using a spacer of about 5
Press for 5 minutes with a load of kg/ci. Next, this is cured in a dryer at 170°C for 20 minutes to obtain a sheet-like cured product with a size of approximately 1 cylinder. Then, this cured product was made into a 5m wide
m, cut to a length of 100 mm, and use it as a sample for a viscoelasticity measuring device.

Measuring method of mechanical loss coefficient: The above sample was measured at a torsion angle of about 1° from -50°C to +150°C using the above-mentioned torsional free damping type viscoelasticity measuring device.

(Margin below) Table 1 The explanation of the note symbols in Table 1 is as follows ■) Bisphenol A type epoxy resin (Oilized shell epoxy ■
2) Dimer acid modified epoxy resin (manufactured by Yuka Shell Epoxy ■) 3) Castor oil modified epoxy resin (manufactured by N.C.R. ■
4) Rubber-modified epoxy resin (manufactured by Asahi Denka Kogyo ■) 5) Urethane-modified epoxy resin (manufactured by Asahi Denka Kogyo ■) 6) Glycidyl methacrylate-modified acrylonitrile-butadiene copolymer (B,
F, manufactured by Gutdrich) 7) Acrylonitrile-butadiene copolymer having carboxyl groups at both ends (B,
F, manufactured by Gutdrich) 8) PEG #200 diacrylate (manufactured by Kyoeisha Yushi Kagaku Kogyo ■) (The scolding in the m1 table is a heavy old hatred.) 9) Table 2 10) 11) Dimethylurea of L-butylperoxy-2-ethylhexanoate) 50% diluted product (manufactured by NOF ■) 3-(3,4-dichlorophenyl)-1,1-dimethylurea (manufactured by Maruwa Biochemical ■) ) (Hereafter the margin) (<1 in Table 2 indicates 1 or less.) The above-mentioned second
As is clear from the results in the table, the resin composition of the present invention
It was confirmed that it has excellent heat resistance and adhesion to oil surfaces, and has excellent performance as a structural adhesive.

Furthermore, as shown in FIGS. 1 and 2, it was confirmed that the resin composition of the present invention has excellent distribution characteristics over a wide temperature range M from extremely low temperatures to high temperatures.

[Brief explanation of drawings]

FIG. 1 is a graph showing the mechanical loss coefficients of Examples 1 to 7, and FIG. 2 is a graph showing the mechanical loss coefficients of Comparative Examples 1 to 3. 1st

Claims (2)

[Claims] (1) (a) Epoxy resin, (b) Acrylonitrile-butadiene copolymer having polar groups at both ends, (c) (meth)acrylate having one or more acryloyl groups, (d) Organic peroxide, ( e) An epoxy resin curing agent. A resin composition comprising: e) an epoxy resin curing agent; (2) The resin according to claim (1), wherein 10 to 80 parts by weight of component (b) and 5 to 50 parts by weight of component (c) are blended with 100 parts by weight of component (a). Composition.