KR101201521B1 - Adhesive compound for backing acrylonitril butadien rubber having low-nitril componenet - Google Patents

Abstract

The present invention relates to a phenolic resin adhesive used for the adhesion of a low nitrile-containing NBR rubber (NBR: Acrylonitile-Butadien Rubber) of the present invention, and more particularly, to a hydrogenated acrylonitrile butadiene rubber (H-NBR) in addition to a phenol resin which is an effective adhesive component. : Hydrogenated Acrylonitile-Butadien Rubber) and a certain amount of fluorine rubber, and the H-NBR rubber and the fluorine rubber provide affinity and heat resistance of the low nitrile-based NBR rubber at the same time, the low-nitrile NBR rubber Provided is an NBR rubber adhesive adhesive composition of a low nitrile component configured to be strongly adhered to a metal.

Description

Adhesive composition for adhesion of envial rubber of low nitrile component {ADHESIVE COMPOUND FOR BACKING ACRYLONITRIL BUTADIEN RUBBER HAVING LOW-NITRIL COMPONENET}

The present invention relates to a phenolic resin adhesive used for the adhesion of a low nitrile component NBR rubber (NBR: Acrylonitile-Butadien Rubber) of the present invention, and more particularly, to a hydrogenated acrylonitrile butadiene rubber containing a phenol resin which is an effective adhesive component. H-NBR: Hydrogenated Acrylonitile-Butadien Rubber) and fluorine rubber provide both affinity and heat resistance of low-nitrile NBR rubber at the same time, thus making it possible to strongly bond low-nitrile NBR rubber to metal. It relates to an NBR rubber adhesive adhesive composition.

NBR (Acrylonitrile-Butadiene Rubber) is a copolymer of butadiene and acrylonitrile. It is low nitrile (18-20 mol%) and medium-low nitrile (ACN content 28-29 mol%) according to acrylonitrile (ACN) content. It can be classified into 5 grades of NBR rubber, heavy nitrile (ACN content 33 ~ 34 mol%), high nitrile (ACN content 38 ~ 39 mol%), ultra high nitrile (ACN content 45 ~ 48 mol%). The physical properties of NBR rubbers are related to the content of acrylonitrile in the rubber, which increases the resistance to hydrocarbon fuels and petroleum fluids, tensile strength, hardness, density, heat resistance, ozone resistance and abrasion resistance. On the other hand, the rebound elasticity, gas permeability, and compressive permanent shrinkage tend to decrease.

NBR rubber is widely used in products such as dustproof rubber, base rubber, rubber rolls, external strips, pressure-resistant hoses, oil seals, rubber linings and gaskets.NBR rubbers of high nitrile and NBR rubbers of ultra high nitrile are generally used for gasoline, etc. Like this, it is used as a material for products that require high resistance to hydrocarbons with high aromatic content, and NBR rubber of heavy nitrile is used as a material for products that do not have swelling problems or in contact with oils with low aromatic content. NBR rubber and NBR rubber of medium and low nitrile are used as materials for products that come into contact with liquids with minimal swelling effects, such as paraffin oil and polyalphaolefin, or products that place more emphasis on low temperature flexibility than oil resistance.

Most of the products manufactured using NBR rubber are manufactured by adhesion of metal and NBR rubber, and there are direct and indirect adhesion methods using vulcanizing adhesives for manufacturing products by bonding NBR rubber and metal. The direct vulcanization method is a method of injecting NBR rubber and metal into a mold without an adhesive, and crosslinking the NBR rubber to bond the metal. In practice, however, the metal and the NBR rubber are first bonded by applying an adhesive to the metal, and then a metal and an unvulcanized rubber in which the adhesive is applied are injected into the molding die, thereby completing the adhesion of the metal with the vulcanization of the rubber. Indirect vulcanization bonding method is mainly used.

In particular, the indirect vulcanization method is generally used when the final product of NBR rubber and metal is contacted with temperature, water, oil, various chemicals, or applied to the harsh environment such as tension, compression, shear, and agitation. Used as

The indirect vulcanizing adhesive is based on the premise of causing an adhesive reaction with the counterpart rubber and needs to be suitable for the use environment conditions of the counterpart rubber material. Indirect vulcanizing adhesives are classified by composition as chlorinated rubber, chlorosulfonated polyethylene (CSM), modified olefin, etc. These are general purpose rubbers (NR), SBR (Styrene-Butadiene Rubber) and BR (Butyl Rubber). , IIR (Isobutylene-Isoprene Rubber) is mainly used for indirect vulcanization. However, the above indirect vulcanizing adhesive is a rubber adhesive such as urethane, NBR, Epichloro-hydrine Ruuber (ECO), Hydrogenated NBR (H-NBR), Acryl Rubber (ACM), etc. requiring oil resistance and heat resistance. This may not be satisfied, and in this case, an adhesive using a heat resistant thermosetting resin is used. In addition, silicone adhesives are widely used in silicone rubber (VMQ) and silicone fluoride rubber (FVMQ) that require heat resistance.

Currently, various chlorinated rubber adhesives are used as adhesives for bonding NBR rubbers. However, since chlorinated rubber adhesives are adhesives based on chlorinated rubber, which is a polar polymer, they cannot be adhesively processed at high temperatures after the adhesive is applied. do. When the chlorinated rubber adhesive is injected into a molding die of about 180 ° C., the chlorinated rubber adhesive melts and contaminates the mold before adhesion with the NBR rubber. There is a problem that the product value is degraded by contaminating the product appearance.

The thermosetting resin-based adhesive is evenly applied to the metal, so that the adhesive film is uniformly applied, so that a large amount of small items can be processed, and the coating workability is good. In addition, it can be used in the temperature range of 150 ~ 200 ℃ depending on the type of thermosetting resin, the type of three-dimensional curing reaction is basically used, oil resistance is also good. However, since a thermosetting resin adhesive is hard, an adhesive film is difficult to use for the adhesive processing of the component which requires bending process.

In the case of phenol resin adhesive, which is a kind of thermosetting resin adhesive, the heat resistance of phenol resin is high, and unlike chlorinated rubber adhesive, it can be adhesively processed at high temperature of 180 ~ 200 ℃ after applying adhesive to metal. After the injection into the mold, the phenomenon that the adhesive melts into the mold before vulcanization adhesion with the rubber does not occur, and the adhesive coating is relatively flexible. As such, the phenolic resin adhesive can be used for adhesive processing of NBR rubber products that require a relatively flexible adhesive coating, and can be extended due to the high heat resistance, thereby preventing mold contamination and contaminating the appearance of the product. It does not lower the commodity value because it does not.

However, the conventional phenol resin-based adhesive, as shown in Figure 1, heavy nitrile (ACN content 33 ~ 34 mol%), high nitrile (ACN content 38 ~ 39 mol%), ultra-high ACN content of more than 30 mol% When the NBR rubber with nitrile (ACN content 45 ~ 48 mol%) is bonded, the adhesion of the adhesive film is excellent, but the affinity with the NBR rubber with low ACN content is insufficient so that the ACN content of the NBR rubber is reduced to 30 mol% or less. At the outset, the peel strength of the adhesive film to the NBR rubber and the residual ratio of the rubber rapidly decrease.

Specifically, NBR rubber and metals having low nitrile (ACN content of 18-20 mol%) and medium-low nitrile (ACN content of 28-29 mol%) having an ACN content of 30 mol% or less using a conventional phenolic resin adhesive inside the mold. When the NBR rubber products are bonded to each other, the peel strength and the rubber residual ratio of the adhesive film between the NBR rubber and the metal are greatly reduced, thereby causing a significant decrease in adhesive strength. Connected. Therefore, it is practically very difficult to produce NBR rubber products by adhering a low nitrile-based NBR rubber and a metal by using a conventional phenolic resin-based adhesive having a phenol resin as a main component, so that a low-nitrile-based NBR rubber can not be bonded. There is a problem.

Accordingly, an object of the present invention is to provide a low nitrile-containing NBR rubber because the hydrogenated acrylonitrile butadiene rubber and the fluorine rubber contained together with the phenolic resin as the effective adhesive ingredient simultaneously impart the affinity and heat resistance of the low-nitrile-based NBR rubber. It is to provide a low-nitrile component NBR rubber adhesive adhesive composition configured to be strongly adhered to a metal.

In order to achieve the above object, in the present invention, a phenol resin adhesive, hydrogenated acrylonitrile butadiene rubber and fluorine rubber is provided, the adhesive composition for NBR rubber adhesive of the low-nitrile component is provided.

Preferably, the adhesive composition comprises 4 to 25% by weight of hydrogenated acrylonitrile butadiene rubber and 2 to 15% by weight of fluororubber.

More preferably, the adhesive composition contains 6 to 14% by weight of hydrogenated acrylonitrile butadiene rubber and 3 to 7% by weight of fluororubber.

The adhesive composition for NBR rubber adhesion of the low-nitrile component according to the present invention simultaneously gives affinity and heat resistance of hydrogenated acrylonitrile butadiene rubber and fluorine rubber to NBR rubber of low nitrile component, and thus, NBR rubber of low nitrile component in the mold. Strong adhesion to metals has the effect of supporting the manufacture of high quality NBR rubber products.

In addition, the adhesive composition for NBR rubber adhesion of the low-nitrile component of the present invention can be subjected to adhesive processing at high temperatures, and the adhesive coating is relatively flexible and has an effect suitable for adhesive processing of NBR rubber products requiring bending processing.

1 is a chart showing the peel strength and residual rubber ratio of a conventional phenolic resin adhesive according to the ACN content of NBR rubber
Figure 2 is a chart showing the peel strength and rubber residual ratio of the phenolic resin adhesive of the present invention according to the ACN content of NBR rubber

The present invention provides affinity and heat resistance of hydrogenated acrylonitrile butadiene rubber and fluorine rubber with NBR rubber of low nitrile component together with phenolic resin as an effective adhesive component, thereby reducing the low nitrile component of ACN content of 30 mol% or less. It is a technical idea to provide an adhesive composition for NBR rubber adhesion of a low nitrile component capable of strongly adhering NBR rubber to a metal.

With reference to the Example, the adhesive composition for NBR rubber adhesion of the low nitrile component of this invention is demonstrated in detail.

The adhesive composition for NBR rubber adhesion of the low nitrile component of the present invention comprises hydrogenated acrylonitrile butadiene rubber (H-NBR) and fluorine rubber in addition to phenol resins and solvents such as toluene, methyl ethyl ketone and ethanol.

It can be adhesively processed at a high temperature of 180 ~ 200 ℃, and it is used for the adhesive processing of NBR rubber products which require a relatively flexible adhesive film, and is mainly composed of phenol resin for adhesive and toluene, methyl ethyl ketone, and ethanol. Conventional phenolic resin adhesives containing solvents such as heavy nitrile having an ACN content of more than 30 mol% (ACN content of 33 to 34 mol%), high nitrile (ACN content of 38 to 39 mol%), ultra high nitrile (ACN 45 ~ 48 mol%) of NBR rubber, the adhesion of the adhesive film is excellent, but it lacks the affinity with NBR rubber with low ACN content, and when the ACN content of NBR rubber starts to drop below 30 mol%, There is a problem in that the peel strength of the adhesive film to the NBR rubber and the rubber residual ratio are sharply lowered.

In order to solve this problem, the present inventors conducted continuous research and repetitive experiments, and as a result, hydrogenated acrylonitrile butadiene rubber (H-NBR) formed by modifying NBR rubber has excellent affinity with NBR rubber of low nitrile component. And flexible properties. Accordingly, the adhesive composition containing hydrogenated acrylonitrile butadiene rubber (H-NBR) together with the phenol resin for the adhesive, which is an effective adhesive component, can strongly adhere the low-nitrile component NBR rubber to the metal in the mold. The film is relatively flexible and is suitable for the adhesive processing of NBR rubber products that require bending.

However, the content of acrylonitrile group in the molecule is a very important factor in determining the adhesion of the hydrogenated acrylonitrile butadiene rubber (H-NBR) contained in the adhesive composition. When the acrylonitrile group is less than 25 mol% in the hydrogenated acrylonitrile butadiene rubber (H-NBR) molecule, the adhesive strength of the hydrogenated acrylonitrile butadiene rubber (H-NBR) is very insufficient, and thus it is included in the adhesive composition of the present invention. Hydrogenated acrylonitrile butadiene rubber (H-NBR) is essential to have at least 25 mol% of acrylonitrile groups in the molecule. In addition, when the content of acrylonitrile group is less than 30 mol% in the hydrogenated acrylonitrile butadiene rubber (H-NBR) molecule, the adhesion of the hydrogenated acrylonitrile butadiene rubber (H-NBR) is insufficient, and the hydrogenated acrylonitrile When the content of acrylonitrile group in the butadiene rubber (H-NBR) molecule exceeds 50 mol%, the hydrogenated acrylonitrile butadiene rubber (H-NBR) is cured, so the acrylonitrile group is 30 to 50 mol in the molecule. It is preferable to use the hydrogenated acrylonitrile butadiene rubber (H-NBR) with which% is provided. However, when the hydrogenated acrylonitrile butadiene rubber (H-NBR) maintains the properties of the rubber even when the content of acrylonitrile group exceeds 50 mol% in the molecule, the hydrogenated acrylonitrile butadiene rubber (H -NBR) can be used to construct the adhesive composition.

As described above, the hydrogenated acrylonitrile butadiene rubber (H-NBR) included in the adhesive composition has a property of insufficient heat resistance. When the adhesive composition containing the hydrogenated acrylonitrile butadiene rubber (H-NBR) is injected into a high temperature molding mold, the adhesive composition melts and contaminates the mold before adhesion of the low nitrile component to the NBR rubber occurs. In addition to frequent mold cleaning, the surface of the product is contaminated by the mold surface contaminated with the adhesive composition, resulting in a decrease in product value.

When the adhesive composition is prepared by containing a phenolic resin, which is an effective adhesive component, and a hydrogenated acrylonitrile butadiene rubber (H-NBR) that provides affinity with NBR rubber of a low nitrile component, other materials providing other heat resistance, The content of the phenol resin is relatively lowered, thereby lowering the adhesive strength of the adhesive composition, or the material providing the heat resistance is not properly mixed with the phenol resin, hydrogenated acrylonitrile butadiene rubber (H-NBR), or the adhesive composition. There is a problem that it is not suitable for adhesion processing of NBR rubber products that require bending, since the adhesive coating of the resin is cured.

In order to solve this problem, the present inventors conducted continuous research and development and repeated experiments, and as a result, fluorine rubber has excellent heat resistance, a considerable degree of adhesion, and a phenol resin and hydrogenated acrylonitrile butadiene rubber (H- NBR) and found that it satisfies all requirements that the adhesive coating should not be cured.

When the hydrogenated acrylonitrile butadiene rubber (H-NBR) and fluorine rubber are mixed with a phenol resin which is an effective adhesive component and a solvent to form an adhesive composition, the hydrogenated acrylonitrile butadiene rubber (H-NBR) may be a low nitrile component. While providing affinity with NBR rubber, the fluorine rubber imparts heat resistance and some adhesion. Therefore, when the NBR rubber of the low nitrile component having an ACN content of 30 mol% or less is bonded to the metal using the adhesive composition as described above, the peel strength and the rubber residual ratio of the adhesive film are greatly improved, thereby improving the adhesive strength. will be.

Specifically, in addition to a phenol resin and a solvent such as toluene, methyl ethyl ketone, ethanol, etc., hydrogenated acrylonitrile butadiene rubber (H-NBR) and fluorine rubber are uniformly mixed to form an adhesive composition, wherein the adhesive composition is hydrogenated acrylonitrile. It is composed of 4 to 25% by weight of butadiene rubber and 2 to 15% by weight of fluorine rubber.

When the content of hydrogenated acrylonitrile butadiene rubber (H-NBR) contained in the adhesive composition is less than 4% by weight, the adhesive composition of the low nitrile component to NBR rubber is reduced, and the hydrogenated acrylonitrile contained in the adhesive composition When the content of butadiene rubber (H-NBR) exceeds 25% by weight, the content of the phenol resin, which is an effective adhesive component, in the adhesive composition is relatively decreased, thereby lowering the adhesive strength of the adhesive composition. In addition, when the content of the fluororubber contained in the adhesive composition is less than 2% by weight, the heat resistance of the adhesive composition is lowered. When the content of the fluororubber contained in the adhesive composition is more than 15% by weight, it is an effective adhesive component in the adhesive composition. The content of the phenolic resin is relatively reduced to lower the adhesive strength of the adhesive composition or the content of hydrogenated acrylonitrile butadiene rubber (H-NBR) is relatively reduced to reduce the adhesion of the low nitrile component to the NBR rubber as well as fluorine. Since rubber is expensive, the price of the adhesive composition is increased.

In addition, the adhesive composition is composed of 6-14% by weight of hydrogenated acrylonitrile butadiene rubber and 3-7% by weight of fluororubber together with the phenol resin which is an effective adhesive component. It is preferable at the point that it can provide simultaneously.

Ultimately, an adhesive composition consisting of 20% by weight of phenolic resin, 10% by weight of hydrogenated acrylonitrile butadiene rubber, 5% by weight of fluororubber, 20% by weight of toluene, 30% by weight of methylethylketone and 15% by weight of ethanol is inherent in phenolic resin. Particular preference is given in view of the best adhesion, balance of low nitrile component to NBR rubber and heat resistance, ease of preparation of the composition, and economy.

The low-nitrile-component NBR rubber adhesive adhesive composition formulated based on the above-described composition ratio provides the chemical affinity necessary for the reaction of the hydrogenated acrylonitrile butadiene rubber and the fluorine-containing rubber with the nitrile component of the NBR rubber. When the NBR rubber and the metal are bonded to the low-nitrile component, the peel strength and the rubber residual ratio of the adhesive film are greatly improved, thereby improving the adhesive strength.

The adhesive composition for NBR rubber adhesion of the low nitrile component of this invention is demonstrated in detail with reference to a specific and most preferable Example. However, the following examples are only for illustrating the present invention in detail and do not limit the present invention, the present invention is limited only by the claims.

<Production of Adhesive Composition>

400 g of a phenol resin, 200 g of hydrogenated acrylonitrile butadiene rubber, 100 g of fluorine rubber, 400 g of toluene, 600 g of methyl ethyl ketone and 300 g of ethanol were injected into the reactor and stirred, and the adhesive composition according to the preferred embodiment of the present invention was stirred. Was prepared, and the adhesive composition was half-divided into a first deposition tank and a second deposition tank, respectively.

Preparation of NBR Rubber Sample

In order to investigate the adhesion between metal specimens according to the ACN content of NBR rubber, NBR rubber (Brand name NT1846, ACN content 18 mol%) of Bayer, Germany, and NBR rubber (Brand name B6280, ACN content 33 mol%) of Hyundai Petrochemical ) Were individually mixed based on the mixing ratio of Table 1 below, to prepare samples of NBR rubbers having different ACN contents.

division Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 NT1846 (% by weight) 100 86 73 60 45 31 20 4 - B6280 (wt%) - 14 27 40 55 69 80 96 100 ACN content (%) 18.0 20.0 22.0 24.0 26.0 28.0 30.0 32.0 33.0

Manufacture of Metal Specimens

The metal specimen to be bonded to NBR rubber is cut 60 × 25 × by cutting and processing SPCC (containing 99.295 wt% Fe, 0.12 wt% C, 0.50 wt% Mn, P 0.04 wt%, etc.) which is a cold rolled steel sheet according to Japanese JIS standard. A plurality of specimens of 2 mm standard were formed.

The surface of each specimen was treated with trichloroethane to remove oil, and then treated with zinc phosphate to prepare a metal specimen having an increased specific surface area.

Preparation of Adhesion Test Specimens

The metal specimen was immersed in the adhesive composition at room temperature of the first deposition tank for 1 minute and taken out, and then heat-treated at 180 ° C. for 13 minutes, and then again immersed in the adhesive composition at room temperature of the second deposition tank for 1 minute and taken out and heat-treated at 150 ° C. for 10 minutes. Thereby forming an adhesive-coated metal specimen.

The adhesive coated metal specimens and NBR rubber samples were placed in a mold and subjected to vulcanization at 180 ° C. for 8 minutes to prepare NBR rubber-bonded test specimens having different ACN contents.

The peel strength and the rubber residual ratio for each of the adhesive test specimens prepared above were measured based on the following method, and the results are shown in the chart of FIG. 2.

<Measurement of peeling strength>

For each of the adhesion test specimens, the peel strength was measured by pulling under a condition of a tensile rate of 50 mm / min using an universal test machine (Model 4465) of Instron according to ASTM M 6518. It was.

When measuring the peel strength, one end of the NBR rubber was peeled 15 mm long from the metal specimen with a sharp knife before applying the load to the adhesive test specimen, and then the other end of the NBR rubber was fastened to the forceps of the tester and peeled off by applying a load. Peel strength of the adhesion test specimen was calculated based on the following equation.

Peel Strength (kgf / cm) = Peel Load (kgf) / Width of NBR Rubber (cm)

<Measurement of Rubber Residual Rate>

The NBR rubber was peeled off from the adhesion test specimen, the area where the rubber remained in the metal specimen in which the NBR rubber was peeled off was measured, and the rubber residual ratio was measured as the measured rubber residual area.

In the chart of FIG. 2, even when the adhesive composition of the present invention adheres metals with NBR rubber having an ACN content of 30 mol% or less, the peel strength and the rubber residual ratio of the adhesive coating are maintained as it is. It can be confirmed that the NBR rubber having a low nitrile component having an ACN content of 30 mol% or less can be strongly adhered to the metal.

<Control group>

The metal specimen was immersed in a phenol resin adhesive (product name 715A) of Rohm & Haas (product name 715A) for 1 minute, and heat-treated at 180 ° C. for 13 minutes, followed by the phenol resin adhesive of Rohm & Haas (product name). 715A) was deposited for 1 minute, taken out, and heat treated at 150 ° C. for 10 minutes to form an adhesive coated metal specimen.

The adhesive-coated metal specimen and a sample of NBR rubber having an ACN content of 30 mol% were placed in a mold and subjected to vulcanization at 180 ° C. for 8 minutes to prepare an adhesion test specimen to which NBR rubber having an ACN content of 30 mol% was bonded as a control.

The peel strength and the rubber residual ratio of the adhesion test specimen, which is the control group, and the adhesion test specimen made by adhering an NN rubber having an ACN content of 30 mol% based on Example 1 were measured, and the results are shown in Table 2 below. Indicates.

division Example 1 Control group Peel Strength (kgf / cm) 16 10 Rubber residual rate 98 90

In Table 2, even when the adhesive composition of the present invention bonds metal with NBR rubber having an ACN content of 30 mol% and a metal, compared to the conventional phenolic resin adhesive, the peeling strength and the rubber residual ratio of the adhesive film are better, and thus the adhesion-related properties It can be seen that this is improved.

Claims (7)

In the NBR rubber adhesive adhesive composition used for the adhesion between NBR rubber and metal, the NBR rubber adhesive adhesive composition,
Phenolic resins;
menstruum;
Hydrogenated acrylonitrile butadiene rubber (H-NBR: Hydrogenated Acrylonitile-Butadien Rubber); And
Include fluorine rubber,
The content of acrylonitrile group contained in the NBR rubber is NBR rubber adhesive composition, characterized in that less than 30mol%. The method of claim 1,
For the whole NBR rubber adhesive composition,
The content of the hydrogenated acrylonitrile butadiene rubber is 1 to 25% by weight, and the content of the fluororubber is 2 to 15% by weight NBR rubber adhesive adhesive composition. The method of claim 2,
The content of the hydrogenated acrylonitrile butadiene rubber is 6 to 14% by weight, the content of the fluorine rubber is 3 to 7% by weight NBR rubber adhesive adhesive composition. The method of claim 1,
The NBR rubber adhesive adhesive composition, characterized in that the content of acrylonitrile group contained in the hydrogenated acrylonitrile butadiene rubber is 25 to 50 mol%. The method of claim 1,
When the NBR rubber and the metal are bonded with the NBR rubber adhesive adhesive composition,
Adhesive composition for NBR rubber adhesive, characterized in that the adhesive film having a peel strength of 15 to 20kgf / ㎠ between the NBR rubber and the metal.
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