KR102224204B1 - Anti vibration pad of low specific gravity with improved anti vibration property at high temperature - Google Patents

Abstract

The present invention relates to a vibration damping pad of low specific gravity with improved vibration damping properties at high temperatures. More particularly, the present invention relates to a vibration damping pad of low specific gravity, comprising a vibration damping sheet made of a composition containing butyl rubber, polyisobutylene and a flow inhibitor, wherein the composition of the vibration damping sheet further includes glass bubbles, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber, and polybutene.

Description

Anti vibration pad of low specific gravity with improved anti vibration property at high temperature}

The present invention relates to a low specific gravity vibration damping pad, and more particularly, to a low specific gravity vibration damping pad with improved vibration damping properties at high temperatures.

Conventional automobiles use vibration damping materials such as roof panel, dash panel, floor panel, side panel, door panel, etc. for the purpose of reducing vibration. As the material of vibration damping material, there are asphalt-based materials and rubber-based materials, and most of these materials have a high specific gravity, which causes musculoskeletal disorders of workers due to manual load problems, and vibration suppression performance as the weight of the vehicle increases and the temperature increases. There was a problem with this decreasing.

As a conventional technology, Patent No. 232094 includes acrylic resin emulsion or vinyl acetate resin emulsion 15 to 35% by weight, filler 30 to 40% by weight, antifoaming agent 2 to 6% by weight, emulsifier 2 to 7% by weight, stabilizer 0.3 to 3% by weight. , 1 to 5% by weight of deionized water, 0.3 to 3% by weight of a foaming agent, 10 to 30% by weight of mica powder, and 1 to 6% by weight of a phenolic resin adhesive are disclosed. The composition has been evaluated as a composition having superior sealing properties and vibration damping properties compared to the conventional one, but has a limit in weight reduction due to its high specific gravity, and there is room for improvement in vibration damping properties as well.

In order to solve this problem, Korean Patent Application Publication No. 2010-0083422 is configured to include a resin mixture, a filler, a defoamer, an emulsifier, a dispersant, a heat-resistant stabilizer, a freeze stabilizer, deionized water, a foaming agent, a pigment, mica powder, and a phenol resin-based adhesive. , It discloses a vibration damping paste-like composition that can be used by integrating a sealing function and a vibration suppression function in an automobile panel, can reduce the weight of the vehicle, and has excellent vibration suppression performance at high temperatures. However, Patent Publication No. 2010-0083422 has a specific gravity of 1.18 to 1.19, and the weight reduction effect is still insignificant.

On the other hand, as a conventional low specific gravity vibration damping sheet, Registered Patent No. 733619 adds glass bubbles having excellent weight reduction effect properties to a vibration damping sheet composition containing butyl rubber, polyisobutylene, flow inhibitor and carbon black, and as a tackifier. By containing maleic anhydride polyetherene wax and polybutene having a specific molecular weight, the problem of the heavy weight of the conventional vibration damping sheet has been solved, but there is a problem that the vibration damping property is reduced at high temperatures.

Accordingly, the present inventors are studying a low specific gravity vibration suppression pad with improved vibration damping at high temperatures, in a low specific gravity vibration suppression pad comprising a vibration suppression sheet made of a composition containing butyl rubber, polyisobutylene, and a flow inhibitor, When the composition of the vibration damping sheet further includes mica modified with glass bubbles, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber, polybutene and titanium dioxide, the present invention is improved by confirming that vibration damping properties and impact resistance are improved at high temperatures. Completed.

Republic of Korea Patent Registration No. 733619 (announcement date 2007. 06. 28)

Accordingly, an object of the present invention is to provide a low specific gravity damping pad with improved vibration damping at high temperatures.

Another object of the present invention is to provide a low specific gravity vibration isolation pad with improved vibration damping properties and impact resistance at high temperatures.

In order to achieve the above object, a low specific gravity vibration suppression pad with improved vibration damping at high temperatures according to an embodiment of the present invention includes a vibration suppression sheet made of a composition containing butyl rubber, polyisobutylene, and a flow inhibitor. In the vibration suppression pad, the composition of the vibration suppression sheet further comprises glass bubbles, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber, and polybutene.

In addition, in the low specific gravity vibration damping pad with improved vibration damping at high temperature according to an embodiment of the present invention, the composition of the vibration damping sheet comprises 2 to 6 parts by weight of polyisobutylene, and 11 parts by weight of the anti-flow agent based on 10 parts by weight of butyl rubber. ~15 parts by weight, 8 to 12 parts by weight of glass bubbles, 8 to 12 parts by weight of carbon nanotubes, 13 to 17 parts by weight of polyvinyl acetal resin, 1 to 3 parts by weight of stearic acid, 8 to 12 parts by weight of styrene butadiene rubber and polybutene It is characterized by containing 24 to 28 parts by weight.

In addition, in the low specific gravity vibration damping pad with improved vibration damping at high temperatures according to an embodiment of the present invention, the composition of the vibration damping sheet further comprises a mica modified with titanium dioxide.

In addition, in the low specific gravity vibration damping pad with improved vibration damping at high temperature according to an embodiment of the present invention, the composition of the vibration damping sheet further comprises 8 to 10 parts by weight of mica modified with titanium dioxide.

In addition, in the low specific gravity vibration damping pad with improved vibration damping at high temperature according to an embodiment of the present invention, the mica modified with titanium dioxide is a mixture of acetic acid, distilled water, and titanium tetraisopropoxide (TTIP). It is characterized in that it is prepared by adding a mica dispersion dispersed with distilled water to the TTIP mixed solution.

According to the low specific gravity vibration damping pad with improved vibration damping at high temperatures of the present invention, the composition of the vibration damping sheet further includes glass bubbles, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber, and polybutene, thereby improving vibration damping at high temperatures. Has an excellent effect of being.

In addition, the composition of the vibration damping sheet includes mica modified with glass bubbles, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber, polybutene and titanium dioxide, thereby improving not only vibration damping properties but also excellent impact resistance at high temperatures. There is.

Since the present invention can apply various transformations and can have various embodiments, a preferred embodiment will be described in detail.

In the low specific gravity vibration isolation pad comprising a vibration isolation sheet made of a composition containing butyl rubber, polyisobutylene, and a flow inhibitor, the low specific gravity vibration isolation pad with improved vibration damping at high temperatures according to an embodiment of the present invention, wherein the vibration isolation sheet The composition of the glass bubble, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber and polybutene further comprises.

In the present invention, glass bubbles having a specific density, carbon nanotubes, polyvinyl acetal, stearic acid, styrene butadiene rubber and polybutene are added as fillers to a vibration damping sheet composition containing butyl rubber, polyisobutylene and a flow inhibitor. A composition was prepared, and it is a low specific gravity vibration damping sheet composition that has a lower specific gravity than the existing composition due to the characteristics of a low specific gravity filler and has excellent vibration resistance as well as impact resistance at high temperatures.

Butyl rubber (isobutylene-isoprene copolymer) has a property that contributes to vibration damping, and its amount is used in the range of 8 to 12 parts by weight, and if it is less than 8 parts by weight, vibration damping property is lowered due to deterioration of viscoelastic function. If it exceeds parts by weight, the workability is lowered due to excessive rubber content.

Polyisobutylene has a property of improving viscoelasticity by blending with butyl rubber, and its usage is in the range of 2 to 6 parts by weight, and when it is less than 2 parts by weight, there is a problem that the flexibility and workability effect are deteriorated, and 6 parts by weight When the amount is exceeded, the problem of increasing the hardness of the composition occurs.

The anti-flow agent acts to eliminate flow when attached to the vertical part, and uses fatty acid-coated calcium carbonate with excellent oil absorption properties, and the amount used is in the range of 10 to 40 parts by weight, and flowability decreases when it is less than 20 parts by weight. And, when it exceeds 40 parts by weight, there is a problem that the hardness increases, and 11 to 15 parts by weight are preferable.

Glass bubbles are used as the filler used in the present invention, and the glass bubbles have the characteristics of lowering the specific gravity of the product and exhibiting vibration damping performance, using borosilicate glass bubbles with a density of 0.3 to 0.5 (g/cc), and having a density of 0.3. If it is less than (g/cc), workability and vibration suppression performance are deteriorated, and if it exceeds 0.5 (g/cc), the specific gravity of the product increases. The amount used is in the range of 6 to 30 parts by weight, and if less than 6 parts by weight, the specific gravity increases and the vibration damping performance decreases, and if it exceeds 30 parts by weight, the high-temperature impact property decreases, causing difficulties in dispersion and mixing, and 8 to 12 parts by weight. Part by weight is preferred.

The carbon nanotubes may be selected from single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, or mixtures thereof. For example, the carbon nanotube particles may be multi-wall carbon nanotubes. When the carbon nanotube particles are multi-walled carbon nanotubes, the diameter may be 5 nm to 30 nm, and the length may be 3 μm to 40 μm.

In one embodiment of the present invention, carbon nanotubes have excellent affinity with butyl rubber, polyisobutylene, styrene butadiene rubber, and polybutene, and play a role in improving vibration damping at high temperatures. For this, the carbon nanotubes are preferably 8 to 12 parts by weight.

Polyvinyl acetal imparts mixing and tackiness of carbon nanotubes in the composition, and is preferably 13 to 17 parts by weight.

Stearic acid improves the storage stability of the composition, and if it is added in an excessive amount, vibration damping properties and adhesive strength may decrease, so 1 to 3 parts by weight is preferable.

Styrene butadiene rubber and polybutene are used to impart self-adhesive performance, and styrene butadiene rubber is preferably 8 to 12 parts by weight, and polybutene is preferably 24 to 28 parts by weight.

In addition, in order to improve impact resistance at high temperatures, the composition of the vibration damping sheet may further include mica modified with titanium dioxide. At this time, the mica modified with titanium dioxide is preferably 8 to 10 parts by weight.

Hereinafter, the present invention will be described in more detail through examples, but the following examples are for illustrative purposes only, and are not intended to limit the scope of the present invention.

<Example 1>

10 parts by weight of butyl rubber and 4 parts by weight of polyisobutylene are mixed using a roll mill, and this is mixed with 13 parts by weight of a flow inhibitor, 10 parts by weight of glass bubbles, 10 parts by weight of carbon nanotubes, and 15 parts by weight of polyvinyl acetal resin. , 2 parts by weight of stearic acid, 10 parts by weight of styrene butadiene rubber, and 26 parts by weight of polybutene were put into a blender, stirred at 90° C. and 27 RPM, and the composition was completed through a mixing process, and the sheet and release paper formed by extruding with an extruder were laminated. A vibration suppression pad was manufactured through the process of

<Example 2>

In the same manner as in Example 1, but in order to improve high-temperature impact resistance, 10 parts by weight of mica modified with titanium dioxide were additionally mixed in the blender to prepare a vibration suppression pad.

Mica modified with titanium dioxide was prepared as follows. In a 500 mL round-bottom flask, 2.0 g of mica (Na-type fluorophlogopite) and 200 mL of distilled water were added and magnetically stirred at room temperature for 24 h. 7.0 mmole of titanium tetraisopropoxide (TTIP) was added to a mixed solution of 40 mL of acetic acid and 10 mL of distilled water in a 250 mL beaker, and magnetically stirred at 50 °C for 40 min. The mixed solution of TTIP was added to the mica dispersion and magnetically stirred at room temperature for 2 h. The resulting solid material was filtered using a sintered glass filter, washed 5 times with distilled water, and dried in an oven at 60°C. The dried product was fired in an electric furnace (Thermo Scientific) at varying firing temperatures (600 to 1000° C.) and firing time (1 to 3 h) to obtain mica modified with titanium dioxide.

<Comparative Example>

It was carried out in the same manner as in Example 1, but in Comparative Examples 1 to 4, a composition was completed by mixing each component as shown in Table 1 below, and a vibration suppression pad was prepared.

division
(Part by weight) Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Butyl rubber 10 10 10 10 10 10 Polyisobutylene 4 4 4 4 4 4 Flow inhibitor 13 13 13 13 13 13 Glass Bubble 10 10 10 10 10 10 Carbon nanotube 10 5 - 10 10 5 Polyvinyl acetal resin 15 15 15 - 15 15 Stearic acid 2 2 2 2 - 2 Styrene Butadiene Rubber 10 10 10 10 10 10 Polybutene 26 26 26 26 26 26 Mica modified with titanium dioxide - 10 - - - - Carbon black - - 10 - - - Mica - - - - - 5

<Experimental Example>

The test was carried out by the following test method, and the test results are shown in Table 2 below.

1) Specific gravity

A container such as a glass beaker whose volume was known in advance was filled so that no air bubbles or foreign substances entered, and the weight of the composition was measured to obtain specific gravity.

2) vibration damping

The measurement of the vibration loss coefficient, one of the performance of the vibration damper, was carried out in accordance with the Korean Industrial Standard KS F 2808, and the standard of the test piece is 150 ℃ after coating a sample of the composition in a thickness of 2 mm on 20 x 200 mm of 0.8 mm steel sheet. It was used by heating and curing for 30 minutes.

3) Impact resistance

Using a DuPont type impact tester (DuPont type, 1/2"*500g*30), it was measured whether cracks occurred in a specimen manufactured in a size of 1/2"×500g×30cm, and excellent (○), depending on the crack condition, It was judged by classifying it into three stages: good (△) and bad (x).

division Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 importance 0.85 0.87 0.88 0.82 0.84 0.87 Vibration suppression effect 20℃ 0.24 0.26 0.25 0.23 0.23 0.24 40℃ 0.28 0.29 0.20 0.21 0.19 0.20 60℃ 0.26 0.27 0.15 0.18 0.16 0.18 Impact resistance 20℃ ○ ○ △ △ △ ○ 60℃ X ○ X X X X

From the above test results, the vibration damping composition of Example 1 of the present invention exhibits excellent vibration damping properties even when the temperature is increased to 20°C, 40°C, and 60°C. Therefore, it is applied to a vibration damping pad with a low specific gravity and a wide temperature range. It is suitable for use in vehicles running in In addition, the vibration damping composition of Example 2 of the present invention exhibits excellent vibration damping properties at high temperatures as well as excellent impact resistance at high temperatures.

Meanwhile, the above detailed description should not be construed as restrictive in all respects and should be considered as illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (5)

In the low specific gravity vibration damping pad comprising a vibration damping sheet made of a composition containing butyl rubber, polyisobutylene and a flow preventing agent,
The composition of the vibration damping sheet further comprises mica modified with glass bubble, carbon nanotube, polyvinyl acetal, stearic acid, styrene butadiene rubber, polybutene and titanium dioxide. .
The method of claim 1,
The composition of the vibration damping sheet includes 2 to 6 parts by weight of polyisobutylene, 11 to 15 parts by weight of anti-flow agent, 8 to 12 parts by weight of glass bubbles, 8 to 12 parts by weight of carbon nanotubes, based on 10 parts by weight of butyl rubber. Characterized in that it contains 13 to 17 parts by weight of vinyl acetal resin, 1 to 3 parts by weight of stearic acid, 8 to 12 parts by weight of styrene butadiene rubber, 24 to 28 parts by weight of polybutene, and 8 to 10 parts by weight of mica modified with titanium dioxide Low specific gravity vibration suppression pad with improved vibration suppression at high temperatures.
The method of claim 1,
The composition of the vibration damping sheet includes 4 parts by weight of polyisobutylene, 13 parts by weight of anti-flow agent, 10 parts by weight of glass bubbles, 10 parts by weight of carbon nanotubes, 15 parts by weight of polyvinyl acetal resin, and stearic acid based on 10 parts by weight of butyl rubber. 2 parts by weight, 10 parts by weight of styrene butadiene rubber, 26 parts by weight of polybutene, and 10 parts by weight of mica modified with titanium dioxide.
The method of claim 1,
The composition of the vibration damping sheet is a mixture of butyl rubber and polyisobutylene using a roll mill, and the mixed butyl rubber and polyisobutylene as a flow inhibitor, glass bubble, carbon nanotube, polyvinyl acetal resin , Stearic acid, styrene butadiene rubber, polybutene, and titanium dioxide-modified mica and put in a blender and agitated to form a low specific gravity vibration damping pad with improved vibration damping properties at high temperatures.
The method of claim 1,
The mica modified with titanium dioxide is prepared by adding a mica dispersion dispersed with distilled water to a TTIP mixture solution of acetic acid, distilled water, and titanium tetraisopropoxide (TTIP). This improved low specific gravity damping pad.