JPH0460065B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention effectively utilizes iron concentrate slag, a by-product of the copper smelting process, and mixes it with a powdered lead compound to create a high-density sound-insulating filler. The present invention relates to a sound insulating material which has improved workability and flexibility by using a liquid rubber that can disperse the filler well. (Prior art) Noise includes traffic noise such as cars, trains, and airplanes, as well as external noise from nearby facilities such as factories, schools, parks, and ball fields, and internal noise generated within the same residence. There is something. Musical noise from televisions, stereos, pianos, etc. is also a serious social problem in residential areas. In order to obtain a sound insulation material that has a high blocking effect against these noises, it is necessary to use the sound insulation mass law [TL = a log mf + b, TL is transmission loss (dB), m is Areal density (Kg/m ² ), f is frequency (Hz),
a, b are constants], it is necessary to mix a filler with a large specific gravity into a binder material with good processability. Therefore, the sound insulation material is made flexible by mixing a filler with a high specific gravity into an organic binder material, and the specific gravity of the sound insulation material is increased to enhance the sound insulation effect. However, when a large amount of filler with small particle size and high specific gravity is mixed into a thermoplastic organic binder material, it is difficult to fill it uniformly, and the matrix of the binder material is extremely diluted, resulting in poor mechanical strength. In addition to insufficient elongation, the binder itself does not have good filling retention ability, resulting in an apparent filling state. That is, the resulting sound insulating material has a problem in that the filler falls off due to contact, vibration, cutting, bending, etc., and the function of the sound insulating material deteriorates. As fillers, heavy metal powders with high specific gravity, heavy metal oxides, carbonate or sulfate barites, iron oxide slag, etc. are usually used. However, metal powders, metal oxides, etc. are preferable due to their high specific gravity, but their high price makes the sound insulating material itself expensive, making it difficult to popularize it as a general building material. Therefore, inexpensive sound insulating materials with high specific gravity are desired. It is rare. On the other hand, the binder material for sound insulation materials for noise prevention is
Since most of them use flammable materials, once they come into contact with flames and burn, they generate a large amount of black smoke and harmful gases, which can hinder fire extinguishing efforts and guided evacuation efforts. (Problems to be Solved by the Invention) In order to solve the above problems, the filler used must have a high specific gravity, be inexpensive, be thermally stable, not generate toxic gas in the event of a fire, and The objective is to obtain a sound insulating material with a high specific gravity (3.0 or more) that can greatly reduce the amount of smoke generated at times, does not cause the filler to fall off, is highly workable, and has excellent flexibility. The present invention aims to solve the above problems and provides a flexible sound insulating material with high specific gravity. (Means for Solving the Problems) The present inventors have completed the present invention as a result of intensive studies to solve the above objects. The structure of the present invention consists of ethylene vinyl acetate copolymer
To 100 parts by weight, 400 to 1500 parts by weight of a sound insulation filler made by mixing iron concentrate slag and powdered lead compound, which are by-produced in the copper smelting process, with a specific gravity of 4.3 or more, and 10 to 70 parts by weight of liquid rubber. It is characterized by being made by blending. Hereinafter, the composition of the sound insulation material according to the present invention will be explained in more detail. The ethylene vinyl acetate copolymer used in the present invention has a vinyl acetate content of 15% by weight or more, preferably 30 to 60% by weight. If the vinyl acetate content is less than 15% by weight, it is not preferable because the sound insulation filler having a specific gravity of 4.3 or more used in the present invention cannot be highly filled, and the desired sound insulation material with a high specific gravity cannot be obtained. The iron concentrate slag that is produced as a by-product in the copper smelting process used in the present invention is made by adding silicon dioxide and oxygen to the matte obtained from the flash furnace in the copper smelting process in a converter to convert it into silicate and oxidize it. Iron concentrate slag is obtained by magnetically separating the generated slag, flotation of the obtained slag, and dehydrating the residue after recovering copper concentrate. An example of the chemical composition of the iron concentrate slag is:
2FeO・_SiO2 (40-50% _by weight as FeO, 15-30% by weight as _SiO2 ), 10-30% _by weight as _Fe3O4 , _Fe2O3
5% by weight, MgO 5% by weight or less, and almost no CaO is contained. Since the iron concentrate slag is a by-product obtained in the copper smelting process, it is inexpensive and produced in large quantities. Moreover, it has undergone flotation,
Advantageously, they are crushed particles. Since the bulk density of the slag is 3 to 4 and the specific gravity is 4 to 4.2, it is preferable as a filler for sound insulation materials. The particle size of the iron concentrate slag used in the present invention is preferably 100 mesh or less, particularly preferably 200 mesh or less. Powdered lead compounds used in the present invention include lead monoxide, lead hydroxide, lead tetroxide, lead sesquioxide, lead dioxide, lead zinc oxide, lead octoxide, lead carbonate, lead sulfate, lead sulfide, etc. Among these, lead monoxide and lead zinc oxide are particularly preferred because of their high specific gravity. Particle size of powdered lead compound is 0.5
A thickness of approximately 100 μm is preferable. A sound insulating filler having a specific gravity of 4.3 or more can be easily obtained, for example, by blending iron concentrate slag powder, which is a by-product in the copper smelting process, and has a specific gravity of 4 to 4.2, and lead monoxide, which has a specific gravity of 9.3. In this case, the particle size of the iron concentrate slag powder is larger than the particle size of the powdered lead compound, so when the two are mixed, the powdered lead compound of smaller particle size enters the void between the larger particle sizes and is uniformly distributed. When mixed, the bulk density is reduced and a product with high specific gravity is obtained. The amount of the sound insulation filler blended is in the range of 400 to 1,500 parts by weight, preferably 500 to 1,300 parts by weight, based on 100 parts by weight of the ethylene-vinyl acetate copolymer. If the amount of the sound insulating filler is less than 400 parts by weight, it is not preferable because a sound insulating material with the desired high specific gravity (3.0 or more) cannot be obtained. On the other hand, if it exceeds 1500 parts by weight, the kneading processability is poor, the resulting sound insulating material lacks flexibility, and its mechanical strength decreases, which is not preferable. The liquid rubber used in the present invention is liquid chloroprene rubber (LCR), butadiene acrylonitrile rubber (NBR), and styrene butadiene rubber (SBR).
In order to modify the ethylene-vinyl acetate copolymer to make it softer and to make it easier to fill with the sound-insulating filler having a specific gravity of 4.3 or higher as described above, it is possible to achieve a high filling rate. Mix together. In particular, those with an LCR molecular weight in the range of 1500 to 2500,
Hiker 1312 from Nippon Seon Co., Ltd. is preferably used as the NBR. The amount of liquid rubber blended is in the range of 10 to 70 parts by weight, preferably 15 to 40 parts by weight, based on 100 parts by weight of the ethylene vinyl acetate copolymer. If the amount of liquid rubber blended is less than 10 parts by weight, it becomes difficult to fill the sound insulating filler to a high level, which is not preferable. On the other hand, if it exceeds 70 parts by weight, it is not preferable because the adhesiveness increases, making it difficult to roll off the sound insulating material sheet, and resulting in poor sheet roll-out processability. In addition, when a plasticizer is blended with the ethylene-vinyl acetate copolymer in the blended composition according to the present invention, the windability around a roll at the initial stage of blending becomes better. Of course, ethylene vinyl acetate copolymer alone may be used. (Examples) Hereinafter, the present invention will be explained in more detail based on Examples and Comparative Examples, but the present invention is not limited only to these Examples. The blended compositions of Examples and Comparative Examples shown in Table 1 were
The mixture was kneaded using an open roll at 150 to 160°C for 10 to 15 minutes to produce sheets with a width of 200 mm and a thickness of about 1 mm. Table 1 also shows the results of examining the various properties shown below for each sheet. Specific gravity: Since sound insulation depends largely on the density of the material, sound insulation was evaluated based on specific gravity. Flexibility: A 30 x 70 x 1 mm test piece was punched out from the prepared sheet, and the test piece was bent 180 degrees to examine its flexibility. ○: No cracks occur. ×: Cracks occur. Workability: When kneading each compounded composition of Examples and Comparative Examples with an 8-inch open roll at 150 to 160°C for 10 to 15 minutes. The wrapping properties, stickiness, and filling properties of the filler were examined and evaluated. ○ mark: Good workability △ mark: Slightly poor workability × mark: Poor workability As can be seen from the results, Examples 1 to 5 showed that the specific compounding materials used in the present invention were not properly applied. Since the sound insulating material has a specific gravity in the range of 3.02 to 4.43, it exhibits good sound insulating properties and also has good flexibility and workability. Next, in Comparative Example 1, the amount of sound insulation filler was not appropriate, so the specific gravity of the resulting sound insulation material was 3.0 or less,
Undesirable. In Comparative Example 2, the amount of sound insulating filler is large, so the flexibility is significantly reduced, which is not preferable.
Comparative Example 3 is not preferable because the vinyl acetate content of the ethylene-vinyl acetate copolymer is low, making it impossible to highly fill the sound insulating filler. Comparative example 4 is a liquid
The large amount of NBR reduces workability. (Effects of the Invention) As explained above, since the flexible sound insulating material according to the present invention uses ethylene vinyl acetate copolymer as the organic binder material, it produces less smoke in the event of a fire, and By effectively using iron concentrate slag, a by-product of iron concentrate, we aim to reduce the need for raw materials by recycling resources, and mix it with powdered lead compounds to create a high-density flexible sound-insulating material as a high-density sound-insulating filler. Since it can be supplied at low cost, it can be used as a sound insulating material for a wide range of building materials. 【table】

Claims (1)

[Claims] 1. Sound insulation filler 400, which is made by mixing 100 parts by weight of ethylene-vinyl acetate copolymer with iron concentrate slag by-produced in the copper smelting process and powdered lead compound to have a specific gravity of 4.3 or more. A flexible sound insulating material characterized by comprising ~1500 parts by weight and 10 to 70 parts by weight of liquid rubber. 2. The flexible sound insulating material according to claim 1, wherein the vinyl acetate content of the ethylene vinyl acetate copolymer is 15% by weight or more. 3. Claim 1, wherein the liquid rubber is one or more of liquid chloroprene rubber, butadiene acrylonitrile rubber, or styrene butadiene rubber.
Flexible sound insulating material as described in section.