JPS6040143A - Resin composition for vibration damping material - Google Patents

Abstract

PURPOSE:The titled composition having improved vibration-damping properties in a wide temperature range from low temperature to high temperature, comprising a styrene-acrylic acid ester copolymer, a vinyl acetate polymer and a polyamide- epoxy compound. CONSTITUTION:(A) 100pts.wt. styrene-acrylic acid ester copolymer is blended with (B) 30-400pts.wt. vinyl acetate copolymer, and (C) 1-400pts.wt. polyamide epoxy compound, to give the titled composition. Addition of a scaly inorganic filler (e.g., mica) to the composition is effective for widening further a usable range of the composition and improving heat resistance.

Description

[Detailed description of the invention] The present invention relates to a novel resin composition for vibration damping materials.

Further details: A composition containing styrene-acrylic acid ester copolymer, vinyl acetate polymer, and polyamide epoxy compound as all essential components, and has performance over a wide temperature range from low to high temperatures. The present invention relates to a resin composition for damping material having excellent vibration damping properties.

Traditionally, we have been manufacturing vehicles, ships, two types of automobile parts, various machines,
In order to prevent vibrations on the surface of structural members such as building materials and acoustic materials, and the associated noise, K, prevent them by making the members themselves thicker or by making improvements to the equipment itself11.
To prevent this, vibration-damping materials have been used. Such vibration-damping materials include sheet-like, film-like, or paint-like materials that are bonded or applied to the surface of structural members (substrates) to an appropriate thickness, and vibration energy is absorbed by the expansion and contraction deformation caused by bending vibrations of the substrate. A non-restrictive damping material that absorbs h'
In addition, there are two types of constraint-type damping materials that have a multilayer structure by laminating a constraint layer with a high elastic modulus on the viscoelastic H・1 and absorb vibration energy through stretching and shearing deformation caused by bending vibration. This is well known. Conventionally, compositions for non-constrained distribution materials that have been disclosed include compositions consisting solely of polymers such as rubber, asphalt lv1, various synthetic resin emulsions, and latex, which have the viscoelastic properties of the polymer itself. There are also those that use polymers filled with inorganic powder such as goufite, mica, vermiculite, calcium carbonate, talc, and clay to increase mechanical hysteresis and internal friction. Examples of material compositions include those containing copolymers such as vinyl acetate and diester maleate, vinyl chloride and ethylhexyl acrylate as main components (Japanese Patent Publication No. 39-1245'1), foamed polyurethane, or polyurethane. Foam rubber and vinyl acetate, modified vinyl acetate, and bituminous substances.

Butyl rubber, acrylic resin, coumaron, indene.

Those made of coumaron-indene and styrene-indene resins (Japanese Patent Publication No. 45-34991), those using polyvinylformer/L' (Japanese Patent Publication No. 46-5830)
, Polyvinylformer)
11975), those whose main component is an acidic copolymer of ethylene and an α/β-monoethylenically unsaturated carboxylic acid in which 5 to 25 wt% of carboxylic acid groups are neutralized to 0 to 50% with metal ions ( Japanese Patent Publication No. 54-1354) and one consisting of a copolymer of acrylonitrile and styrene and a plasticizer (Japanese Patent Publication No. 54-22478) have been disclosed.

However, many of these conventional products are designed to be used at around room temperature, and even though they have high vibration damping performance at around room temperature, they only work in a narrow temperature range around the applicable temperature. It also has the drawbacks of softening in high-temperature atmospheres, extremely decreasing mechanical properties, and poor heat resistance. On the other hand, many materials designed to be applied in relatively high temperature ranges use thermosetting resins, and are therefore organic solvent-based or two-component types consisting of a base agent and a curing agent. Because, made''!#
There were problems with the safety and handling of the fR1 boundary.

In view of the above-mentioned current situation, the present inventors have discovered that a fiber material containing an emulsion-like styrene-acrylic acid ester copolymer, a vinyl acetate polymer, and a scale-like inorganic powder as essential components can be used at low to high temperatures. It is a water-dispersible vibration damping paint that has excellent vibration damping performance over a wide temperature range up to As a result of repeated studies to develop a vibration damping ratio that has a high vibration damping ratio, we found that a composition consisting of a styrene-acrylic acid ester copolymer, a vinyl acetate polymer, and a polyamide epoxy compound has high vibration damping performance over a wide temperature range, including high temperature regions. It was discovered that the present invention can be used for both non-constraint type and constraint type vibration damping materials.

That is, the present invention includes a styrene-acrylic acid ester copolymer (A), a vinyl acetate polymer (uniform) and a polyamide epoxy compound (qf!: an essential component, and component (A) 10
This is a resin composition for a damping material, which contains 30 to 400 parts by weight of component (to) 0 parts by weight, and 21 to 400 parts by weight of component 0.

Theoretical analysis of damping performance is 1. For example, E, E, Ungar
(,I.

Acoustic Soc, Am, vol, 34
+ 1082-1089 + 1962), etc., and the main point is that the damping performance of a structure is determined by the tan δ (dissipation factor, loss tangent) and E'(Young's modulus, real part); in the case of a constrained type, these are the tan δ and G' (shear modulus, real part) of the composition forming the intermediate layer; and in the case of an unconstrained type, The larger the value of janδ E/, the better.

In the constrained type, it is preferable that tan δ is large (]
′ has an optimal value.

Although it is difficult to clearly explain this, the excellent effects of the composition for vibration damping materials of the present invention are probably due to the fact that the jan δ of the styrene-acrylic acid ester copolymer maintains a high level from low to high temperature ranges. 1 of the vinyl acetate polymer.
An δ shows a high level /I/ especially in the low temperature range, and a synergistic effect between the two is expected.The styrene-acrylic acid ester iV copolymer, vinyl acetate polymer, and polyamide epoxy compound are mixed uniformly and in a well-balanced manner. In addition to exhibiting desirable E/ and 0' values, the polyamide epoxy compound suppresses macroscopic flow of the composition through a crosslinking reaction, and can be used in high-temperature atmospheres. It maintains its shape stably even at low temperatures, and is thought to be caused by scales, etc.

Styrene-acrylic acid ester copolymer ij used in the present invention: In addition to styrene, a styrene component consisting of a lower alkyl, lower alkoxy or halogen rust conductor such as 4-methoxystyrene, 4-methylstyrene, 2-chlorostyrene, etc. , usually having about 1 to 10 carbon atoms) acrylic acid methyl.

791J of acrylic acid esters, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc.
It is a copolymer consisting of an alkyl ester component. The composition ratio of the constituent monomers in the copolymer is styrene component 1
It is desirable that the amount of the acrylic acid ester component is 50 to 400 (preferably 80 to 200) parts by weight relative to 00 parts by weight, and if it is out of this range, the effect on damping performance will be small. In the above copolymer, a small amount of a third component may be further copolymerized. For example, monomers having hydroxyl groups, carboxyl groups, etc. may be copolymerized, and acrylic acid, 2-hydroxyethyl acrylate,
Single ff such as 2-hydroxyethyl acrylate/l/
It may be combined in an amount of 0.5 to 10 parts by weight per 100 parts by weight of the styrene-acrylic acid ester component.

The vinyl acetate polymer used in the present invention has a composition ratio of constituent monomers in the polymer of vinyl acetate/l/1.
Examples include a vinyl acetate homopolymer and a copolymer mainly composed of vinyl acetate (vinyl acetate) containing about 0 to 45 parts by weight of a monomer for copolymerization based on 00 parts by weight. Here, as the monomer for copolymerization, ethylene, Ak! J/I' acid,
Acrylic acid alkyl esters may be present, and the copolymer may contain one or more of these.

The polyamide epoxy compound used in the present invention is mixed with epichlorohydrin t (
Epoxidized polyamide polyamines with added =J are preferred. Diamines containing f-class amide 7 groups in the molecule include aliphatic diamines such as diethylenetriamine, I-lyethylenetetramine, and tetophethylenepentamine, and dicarboxylic acids include oxalic acid, malanic acid, and succinic acid. ,
Examples include aliphatic acids such as lv acid, adipic acid, pimelic acid and their alkyl derivatives, phthalic acid, isophthalic acid, terephthalic acid and their alkyl derivatives.

Styrene-acrylic acid ester copolymer of the present invention IA)
, a vinyl acetate polymer (B), and a polyamide epoxy compound (Q).
0 parts by weight, and the component (Cl) is carried out at 21 to 400 parts by weight (preferably 40 to 400 parts by weight). If it is outside this range and the mixing ratio of the vinyl acetate polymer is less than 30 parts by weight, low temperature The allocation performance in the area decreases, and conversely
If the amount exceeds 00 parts of heavy oil, the vibration damping performance in the high temperature range will deteriorate, and a synergistic effect on the vibration damping performance of the styrene-acid ester copolymer and the vinyl acetate polymer cannot be expected. In addition, the mixing ratio of the polyamide epoxy compound is 2
If it is less than 1 part by weight, the crosslinking reaction of the polyamide epoxy compound will proceed, and depending on the reaction conditions, the viscosity of the mixture solution will be too high and the fluidity will be poor, making it unsuitable for practical use. Cases may arise. Also,
If the amount is more than 400 parts by weight, the effect of improving damping properties will appear.
Depending on the manufacturing conditions after the composition is mixed, the composition may not be too hard, making it difficult to obtain E' and G' with good vibration damping properties.

By including the scale-like inorganic powder in the resin composition used in the present invention, the scale-like inorganic powder can be used at the usable temperature, although the peak level of tan δ of the resin composition may be slightly lowered. It has the effect of further expanding the range of gold and improving the heat resistance of resin compositions (suppression of flow at high temperatures of 17 Jl, reduction of decomposed gas generation during spot welding and fusing), and improvement of the heat resistance of resin compositions. It is valid. The flake diameter and aspect ratio of the scaly inorganic powder used in the present invention are not particularly limited, but usually the flake diameter is in the range of 407z+n to 2%, and the weight average aspect ratio is preferably 10 or more. If the flake diameter is too large, the fluidity of the composition when made into a paint is poor.
When spraying, the nozzle sometimes bleeds, making uniform brushing and casting difficult. Also, it is difficult to form it into a sheet or film.

Also, if the flake diameter is too small, the viscosity of the paint will increase and the smooth spraying will become 9 (IF).
The effect of addition on IJ vibration performance becomes smaller.

1. If the heavy ring average aspect ratio is smaller than 10, the effect of addition on vibration damping performance will be small. The scaly +! ! ! !
Although the mixing ratio of organic powder is not particularly limited,
If there is too much sweetener, the effect of addition on vibration damping performance and heat resistance will not increase any further, and the viscosity of the composition will increase too much, reducing workability during production.
) It is preferably 1500 parts by weight or less per 10 parts by weight. Among various scale-like inorganic powders, mica is preferred from the viewpoint of performance and cost.

The resin composition for vibration damping materials according to the present invention includes, for example, emulsion-like components (A) and (13), an aqueous solution-like component ((
It is possible to produce a paint by mixing (a) and gradually adding scale-like inorganic powder while continuing to stir and mix. For example, by mixing (5), (c), (C) After that, it is extruded into a sheet from an extruder, rolled between rolls to a predetermined thickness, or (A), σ(), 0
It can also be manufactured into sheets or films by mixing the essential ingredients, casting it onto heated rollers using a doctor blade, drying it, and rolling it between rolls to a specified thickness. It is possible.

Furthermore, in the resin composition of the present invention, inorganic fillers such as calcium carbonate, silica sand, gypsum dihydrate, various clay minerals, and barium sulfate are used as necessary.

High-density inorganic 'C7 fillers such as iron oxide, iron powder, lead powder,
Rock wool, asbestos, glass RKM, M1
m 1mi+a, bi=IJ y /Irj, 1Mt
m, varnish T/' short He IJU, etc. inorganic and organic fibers, plasticizers, antifoaming agents, thickeners, water repellents, water/4
F may be added.

In the present invention, 1: The resin composition for a vibration damping material is used as a non-restrictive damping material by coating or sealing on the square structure part 4J]
It is also possible to use adhesives formed into a shape or a film, but they have excellent adhesion to the extent that no separate adhesive is required, and even when used in a high temperature atmosphere, the adhesive
Since i does not flow out, it can also be used as a constraint type vibration damping material. As described above, the resin composition for vibration damping materials according to the present invention can be applied to both non-constrained damping materials and constrained damping materials. Alternatively, its performance can be exerted by applying it to a structural member and then drying it. Specifically, the vehicle in slurry form,
Ships, automobile parts (1 machine)) g, Spray spray or 619 on the surface of 41 construction parts such as various machines, or spray or paint on metal plates 1 plywood 2 gypsum boards, cement concrete boards, cement mortar boards, slate boards, etc. Alternatively, the above-mentioned tM structural member can be obtained by dipping a plate or the like in the slurry, applying 1+', f to one surface, and then drying it, so that there is no slurry dripping or the like (1 is completely applied to one material or plate, etc.). If the method of spraying, smearing, or immersing the object in slurry form is used, it is possible to adhere to the object closely and exhibit sufficient distribution performance, especially if the object has a curved or uneven surface. This is very effective when it is difficult for a sheet-shaped damping material to come into close contact with the object sufficiently, such as when a large number of parts or 11 parts are connected.

Furthermore, in ID3 cases in which the resin composition for vibration damping materials according to the present invention is used as a constrained vibration damping material, a slurry or sheet-like or film-like material made of the 411 composition is coated or laminated on the base material, and an intermediate layer is formed. ), a constraining layer material is laminated on the intermediate layer. This base material, intermediate layer, and restraint material are all integrated, and further, bending processing, stress processing,
The desired structural member can also be obtained by performing secondary processing such as grain D7J processing.

The thickness of the composition as an intermediate layer is not particularly limited, and the thicker it is, the better it is for vibration damping properties, but the amount of gas generated during welding and fusing is large, which may be disadvantageous in terms of disaster prevention, and it may be difficult to perform secondary processing. When this happens, problems such as the structural member (base material) and the material for the constraint layer peeling off or wrinkles may occur. The thickness of the through hole should be selected.

Materials for the restraint layer include various steel plates, aluminum plates, copper plates, 2 F-P plates, 1 plywood, 1 stone, 11 boards.

Cement concrete board, cement mortar board.

Examples include slate plates, plastic plates, and various foils. Specifically, the main uses of the resin composition for vibration damping materials of the present invention include blower duct pipe empty % FJIJ
Metal plates for Japanese equipment, hoppers, conveyors, chutes, etc.
Engines and door parts of vehicles, ships, automobiles, etc., piping and parts of refrigerators and heating/cooling units H't'r, casings and backs of office calculators, stainless steel sinks, shutters, roofing materials, and backs of doors. 1. Removing kitchen utensils and building materials such as stairs, sound equipment such as acoustic diaphragms and speaker boxes, and metal plate pipes of soundproof panels that are widely used to prevent factory noise, traffic noise, and vibration. By pasting, spraying, or coating them, or by further providing a restraining layer to form a multilayer structure, it is possible to prevent the solid vibration sound generated.

As described above, the composition for vibration damping material of the present invention can be applied to various articles to damp vibrations and reduce noise due to the vibrations.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples in any way.

Examples 1, 2.5 and Comparative Examples A, B Compositions according to the invention are shown as Examples 1, 2.5, and compositions not according to the invention are shown as Comparative Example A.

8g was shown as B in the table. The composition according to the invention is made up to 1% by adding to the emulsion the polyamide elastomer compound in aqueous solution and, if necessary, a thickening agent, and then gradually adding mica and mixing.

The compositions shown in Table 1 have a coating weight force after drying of 2 k
400 shoulder*X40'Omm(
It was applied with a spray gun onto a cold-rolled steel plate with a thickness of 0.8%, dried for 2 days at room temperature, and then completely dried for 1 hour on a hot air drying table Gc13 at 130°C. The control property fi12 of the obtained test piece is determined by the vibration acceleration level (V
AL) was evaluated by determining 71111. That is, two points of the test piece are suspended by a string, and a steel ball is placed in the center of the test piece to generate vibration.
The magnitude of the existing vibration can be determined by fixing the lower end of the test piece.
It was detected by a vacuum pump and read through a vibration level meter. And the cold rolled j! used as the base material! The difference from the value of the vibration acceleration level of 'i4 only was taken as ΔVAL (d, B) and used as a measure of the vibration reduction effect. That is, vibration 111Jii young fruit △vAL (dB) - t74 plate (Dmi (1) VAL ('dB) - vAL (dB) of the test piece with the composition fully applied to the steel plate, △VA
L (dB), so the larger the directivity, the better the damping performance. The results are shown in Table 2.

As shown in Table 2 below, in the button, the composition according to the present invention:
A high level of vibration reduction effect of 18dB or more can be expected.
Moreover, no decrease in ΔVAL is observed over a wide temperature range. On the other hand, it can be seen that although compositions not based on the present invention exhibit considerably high effects in a certain temperature range, their effects decrease in low or high temperature ranges.

Examples 4, 5, 6, Comparative Examples C, D Compositions based on the present invention are shown as Examples 4, 5, and 6. After uniformly mixing an emulsion of styrene-acrylic ester copolymer, a vinyl acetate polymer, and an aqueous solution of a polyamide epoxy compound, the mixture was cast onto a release paper using a doctor blade and heated to a temperature of 100"C. It was dried under ambient air to produce a film with a thickness of 0.2 JFJl.

A composition not according to the invention is designated as C,l) and a 0.2M thick film was produced in a similar manner. Each blending composition f: shown in Table 3. 1 The film was sandwiched between two cold-rolled steel plates with a thickness of 0.2 mm and hot pressed at a temperature of 180°C (however, Comparative Example C21) would flow, so it would not work for a short time at 100°C. Ta. ) Integrated restraint type vibration damping 1
111 boards were created. Regarding this restrained type side JFA steel plate, the temperature value TF property of the loss factor was measured by the vibration lead method (cantilever beam, resonance method), and the results are shown in Part 11. (#+!l Constant frequency is converted to 50011z) Below margin The composition based on the present invention shows an extremely large loss coefficient over a wide temperature range from low temperature to high temperature, while the composition not based on the present invention shows an extremely large loss coefficient. Although it shows a high loss coefficient in a narrow temperature range, the loss coefficient drops extremely in areas outside of this range, as shown in Table 6.
During processing, the middle layer softened, flowed, and peeled off, making it completely unusable.

Example 7.8 Invention KII! Example 7.8 is shown in Table 4. 0.211J by the same method as the previous ++3 example
A film with a thickness of I was produced, and the temperature dependence of the loss factor was similarly measured. The results are shown in Figure 2.

Table 4 Note 7) Styrene-diethylhexyl acrylate copolymer (copolymerization ratio 2:5) Note 8) Ethylene-vinyl acetate copolymer (containing 18% by weight of ethylene) Note 9) 8UZOaITE MICA (MfR average flake diameter 90.1tm, weight average aspect ratio 50,
Tea Kuraray Sales) Figure 2 shows that by incorporating mica as a scale-like inorganic powder into the resin composition based on the present invention, although the peak level of the loss factor /L/ is slightly lowered, the loss factor curve becomes a broad button. It is clear that it can be used in a wider temperature range.

[Brief explanation of drawings]

Figure 1 is based on the vibration lead method! 711+! FIG. 4 is a diagram showing the temperature dependence of the loss coefficient of Example 4.5.6 and Comparative Examples C and D. Figure 2 shows Example 7, which was also measured using the vibration lead method.
, 8 is a diagram showing the temperature dependence of the loss coefficient of . In the figure, numbers 1 to 7 refer to the loss coefficient measurement results of Examples 4, 5, and 6, Comparative Example C, ]), and Examples 7 and 8, respectively. Patent Applicant: RiRashi Co., Ltd. Agent: Patent Attorney Dobokuta Kendai 1. Degree of clarity ('C) 2. Temperature (°C)

Claims (1)

[Scope of Claims] (1) Styrene-acrylic acid ester/' copolymer (~
, 111: Acid vinyl-based IF combination (uniform and polyamide epoxy compound (C'l 'f: essential component, component (A
) 60 to 400 parts of component (13) per 100 parts by weight
A resin composition for an allocation material, which contains component 0 in an amount of 21 to 400 parts by weight. (7) The styrene-acrylic acid ester copolymer is styrene 100% (1 part nialic acid ester) v50~
The damping material 11J resin composition according to claim (1), which is a copolymer composed of 400 parts ff+:. ('i) The vinyl acetate polymer is vinyl acetate/L'100
Parts by weight: A polymer composed of 0 to 45 parts by weight of 7 polymers.
) The resin composition for vibration damping material according to item 1. (4) The resin composition for a damping material according to claim 1, 2, or 3, further comprising a scaly inorganic powder. (5) The resin composition for an allocation material according to claim (4), wherein the scale-like inorganic powder is mica.