JP3406516B2 - 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 damping material useful for applications such as dampers and damping walls for earthquake-proof reinforcement of buildings.

[0002]

2. Description of the Related Art Conventionally, various damping materials made of polymer viscoelastic materials have been developed for the purpose of preventing vibration generated from general vehicles, floors of buildings, machinery, etc., and soundproofing of acoustic equipment. ing.

[0003]

However, although the conventional damping material exhibits a good damping effect against vibration in a relatively high frequency range of about several tens Hz to several thousands Hz, There is a problem that the damping effect in the low frequency region of several Hz or less is insufficient. Therefore, it has been difficult to apply it to applications such as viscoelastic dampers and damping walls used for seismic reinforcement of buildings and various structures that require damping in a low frequency range.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a vibration damping material exhibiting a good vibration damping effect even in a low frequency region of several Hz or less such as earthquake motion. .

[0005]

The damping material of the present invention is
(A) 100 parts by weight of a liquid diene rubber containing an active hydrogen group, (B) a liquid diene containing an isocyanate group at the end
Of the liquid diene rubber of (A) described above such that the equivalent ratio of active hydrogen groups to isocyanate groups is 1: 0.5 to 0.9, and (C) the bituminous substance is 10 parts by weight or more 50 parts by weight or more.
It is characterized in that it comprises a rubber composition containing less than 1 part by weight.

The liquid diene rubber as the component (A) used in the present invention is a liquid natural rubber or isoprene rubber containing a functional group having active hydrogen, such as --OH or --COOH, at the molecular chain end. Styrene-butadiene rubber,
Examples thereof include butadiene rubber, chloroprene rubber, nitrile butadiene rubber, butyl rubber, halogenated butyl rubber, ethylene propylene diene rubber and polyoxypropylene chloroprene rubber. These may be used alone or in combination of two or more.

Examples of the rubber having an isocyanate group at the terminal of the molecular chain of the component (B) include those having the same main chain component as the above liquid diene rubber and having the terminal substituted with an isocyanate group. Also for these, one kind may be used alone, or two or more kinds may be mixed and used.

In the present invention, such a rubber containing an isocyanate group at the terminal of the component (B) has the above-mentioned (A).
It is used in an amount such that the equivalent ratio of active hydrogen groups to isocyanate groups of the liquid diene rubber as a component is 1: 0.5 to 0.9. By using in such a range, large elongation and linearity at the time of deformation are secured, and as a result, a vibration damping material that exhibits vibration damping performance in a wide range from small deformation to large deformation can be obtained. In addition,
A more desirable amount of the rubber containing an isocyanate group at the terminal of the component (B) is such that the equivalent ratio is 1: 0.65 to 0.
The range is 9.

Next, as the bituminous substance as the component (C), there are straight asphalt, semi-broth asphalt, blown asphalt, etc., and these are one kind or two kinds.
Used as a mixture of two or more species.

The bituminous substance of the component (C) is 10 parts by weight or more per 50 parts by weight of the liquid diene rubber of the component (A), 50 parts by weight or more.
It is blended in less than parts by weight. If it is less than 10 parts by weight, the effect due to addition, that is, the effect of enhancing the damping performance and improving the vibration damping performance is not sufficiently obtained, and if it is 50 parts by weight or more, the rigidity decreases when used in a high temperature atmosphere. Sometimes.

In the present invention, as the fourth component,
It is desirable to blend (D) an aromatic hydrocarbon resin. This aromatic hydrocarbon resin is one type of petroleum hydrocarbon resin, and many products are commercially available as tackifiers for natural rubber and synthetic rubber. In the present invention, one or more of these are used. Can be arbitrarily selected and used. Examples of commercially available products include Nisseki Neopolymer 120 manufactured by Nippon Oil Co., Ltd. and Petrosin (trade name) manufactured by Mitsui Petrochemical Co., Ltd.

The aromatic hydrocarbon resin as the component (D) also has an effect of enhancing the damping performance, similarly to the bituminous substance as the component (C), but if too much is added, the rigidity becomes too high, and when it is slightly deformed. Since it becomes difficult to obtain the vibration damping performance of
It is desirable to add the component (A) in an amount of 10 parts by weight or more and 500 parts by weight or less per 100 parts by weight of the liquid diene rubber. More desirably, the liquid diene rubber as the component (A)
It is 50 parts by weight or more and 200 parts by weight or less per 100 parts by weight.

In the rubber composition used in the present invention, in addition to the above-mentioned components, additives which are usually compounded in this type of rubber composition, for example, fillers such as carbon black and clay, and softening of process oils are also included. Agents, plasticizers, anti-aging agents and the like can be added within a range that does not impair the effects of the present invention.

As described above, in the vibration damping material of the present invention, (A) a liquid diene rubber containing an active hydrogen group, (B) a rubber containing an isocyanate group at the end, and (C) a bituminous substance are added as described above. Since it is mixed in a specific ratio, the vibration damping performance in the low frequency region is improved. Moreover, since the elongation is good and the linearity at the time of deformation is ensured, excellent vibration damping performance is exhibited over a wide range from small deformation to large deformation.

Accordingly, it can be widely used for various applications such as viscoelastic dampers and damping walls for buildings, which require high damping effect in a low frequency region, and general vehicles.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to examples. Needless to say, the present invention is not limited to such an embodiment.

Examples 1 to 5 and Comparative Examples 1 and 2 With the formulations shown in the upper columns of Table 1, the components were uniformly mixed using a stirrer, and then heat-cured into a predetermined shape to obtain a damping material. Got

In order to evaluate the vibration damping performance of these vibration damping materials, two vibration damping material sheets (10 cm × 10 cm × 1 cm) were used, and a small duplexer (shear shear type) as shown in FIG. 1 was used. Create an area of 200.0 cm ² and shear gap of 1.0 cm) at 20 ℃
At the temperature of 10 ° C., vibration with a frequency of 0.2 Hz, amplitude of 10% and 100% was applied, and tan δ and shear modulus G ′ for each vibration were measured. 1A is a top view,
(B) is a side view, and in these figures, 1 is a damping material sheet, 2 is an actuator mounting portion, and 3 is a reaction force frame mounting portion.

The elongation was also measured according to JIS K 6301. The results of these measurements are shown in the lower column of Table 1.

[0020]

[Table 1] As is clear from Table 1, the damping material according to the present invention is
It was confirmed that the damping performance was high and the elongation was large even in the low frequency region, and that a good damping effect was exhibited.

[0021]

As is clear from the above examples, the damping material of the present invention comprises an active hydrogen group-containing liquid diene rubber,
Since the terminal diisocyanate group-containing liquid diene rubber and the bituminous substance are mixed in a specific ratio, not only high frequency regions but also good vibration damping performance in low frequency regions such as earthquake motions, and This excellent vibration damping performance is sufficiently exhibited even during minute deformation or large deformation.

[Brief description of drawings]

FIG. 1A is a top view and FIG. 1B is a side view showing the configuration of a sample for evaluating damping performance of a damping material.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C08L 95:00) (72) Inventor Katsuhiro Teshirogi 2-1-1 Oda Sakae, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Showa Densen Denpa Co., Ltd. (56) References JP 58-189243 (JP, A) JP 58-196227 (JP, A) JP 57-127139 (JP, A) JP 5-320307 (JP, A) Kaihei 5-171135 (JP, A) JP-A-61-261040 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00 C08L 15/00

Claims (2)

(57) [Claims] 1. A liquid diene rubber containing (A) an active hydrogen group.
With respect to 100 parts by weight, (B) the liquid diene rubber having an isocyanate group at the terminal is used, and the equivalent ratio of the active hydrogen groups and the isocyanate groups of the liquid diene rubber of (A) is 1: 0.5.
A vibration-damping material comprising a rubber composition in which the bituminous substance (C) is blended in an amount of up to 0.9, and at least 10 parts by weight and less than 50 parts by weight. 2. The vibration damping material according to claim 1, wherein the rubber composition is (A) an active hydrogen group-containing liquid diene rubber.
A damping material, which further comprises 10 to 500 parts by weight of (D) an aromatic hydrocarbon resin per 100 parts by weight.