JPS6033132B2 - Adhesive bonding method for silicone rubber molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for adhesively bonding a silicone rubber molded article and an object to be adhered using an alpha cyanoacrylate resin adhesive.

Due to its unique skeletal structure, silicone rubber has excellent properties not found in natural rubber or other organic synthetic rubbers, such as 2000
Heat resistance that can be used for long periods of time even in high temperature atmospheres exceeding 0.0 °C, cold resistance without loss of flexibility even at extremely low temperatures of less than 100 °C, weather resistance, electrical insulation, physiological inertness, non-toxicity, etc. Because of these characteristics, its uses have been diversified in a wide range of fields. On the other hand, due to its unique properties, silicone rubber adheres extremely well to silicone rubber and other substances such as metals and plastics.Therefore, in order to achieve good adhesion, various adhesion methods and adhesive methods have been attempted. It is being

For example, methods for adhering silicone rubber molded products include the flow adhesion method using a co-fabric of unwashed silicone rubber, and the use of a condensation-type liquid RTV or self-adhesive two-component RTV as a rigid adhesive. Methods are known, and a method for adhering silicone rubber molded products to other materials is 'iii} Adding and mixing a certain amount of an adhesion aid such as carbon functional silica to unwashed silicone rubber and adhering the product. Method, (iv) A method in which the adhesive surface of the object to be adhered is subjected to primer treatment in advance; M Adhesion is performed using a condensation-curing one-component type RTV or a two-component type RTV having self-adhesive properties as an adhesive. Although there are known methods, each of these has its advantages and disadvantages, and none of them are fully satisfactory.In other words, the method [i} above uses rubber to form a kind of weld line at the adhesive interface. There are disadvantages in that the strength of the main clasp cannot be obtained and it easily peels off due to stress concentration.In addition, in the case of molded products with complex shapes, it is disadvantageous that it requires a great deal of cost to manufacture molds and pick-up tools. have

Also, for the method {ii} and M, the RTV used here is
Adhesive strength is affected by the strength of RTV itself or the thickness of the adhesive layer present at the adhesive interface, and if the molecular weight of polysiloxane is increased to increase the strength of RTV itself, the viscosity of RTV will generally increase. There is a problem in that there is a limit to the improvement of adhesive strength based on the viscosity of RTV, and it is almost impossible to obtain adhesive strength that will cause adhesive failure of silicone rubber molded products. . Furthermore, condensation-curable RTV requires 24 hours or more to cure and exhibit its properties, and addition-reactive RTV has long-curing properties when heated, but condensation-curable two-part Similar to type RTV, it has short pot life and cannot be used after a certain period of time once the catalyst system has been mixed.In addition, it has a high viscosity so that it can be used evenly and with an extremely thin adhesive layer. The disadvantage is that it is difficult to form and to keep the adhesive surface level. Methods [iii) and 'M show excellent adhesive strength without causing rubber damage and are said to be the method of attaching bushes with the best adhesive force among the various methods mentioned above, but methods [iii' This method has the disadvantage that it adheres to the object to be adhered in the mold and also to the mold at the same time by hot-flow curing. In addition, there is a problem in that both the rigid and the ribs are often unable to be simultaneously bonded during hot-flow curing due to the heat resistance and shape of the bonded object. For example, in the case of heat vulcanization adhesion, adhesive molding cannot be performed if the object to be adhered has heat softening properties such as general-purpose plastics, and if the object to be adhered has a complex shape or large size. Similar to the method (i) above, this method has drawbacks such as requiring a large amount of money for molds and jigs.On the other hand, in recent years, Alphasia/acrylate resin has become known as an instant adhesive, and this material can be used with various materials. It adheres extremely well, and its adhesive strength is also extremely strong.
It is difficult to apply it well to silicone rubber due to its specificity, so alpha cyanoacrylate resin adhesives have excellent properties such as instantaneous properties, strength, one-component property, and low viscosity. However, the current situation is that it cannot be applied to silicone rubber.

The present invention solves the above problems and utilizes the excellent properties of alpha cyanoacrylate resin adhesives, such as workability and adhesion, without impairing the excellent properties of silicone rubber. The present invention aims to provide an adhesive bonding method for adhesively bonding a silicone rubber molded article and an adhered material using an alpha cyanoacrylate resin adhesive. It is characterized by being added to the rubber molded product in advance or applied to the surface.

The adhesive bonding method according to the present invention will be described in detail below. The nitrogen atom-containing organic poppy compound used here has the formula R1aR2bXCSi〇4-'b-C a monovalent organic group, R2
is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group that does not contain a nitrogen atom, X is a hydroxyl group or a hydrolyzable atom or group, a, b and c are each 0<a≦
4, 0≦b<4, OSc<4, but a+b+c is 0<
Examples include silanes or siloxanes represented by a+b+cmi4).

Examples of the monovalent organic group containing a nitrogen atom represented by R in the formula include 2N→tH2★, 2N÷CH
2÷TES÷CH2★, N=C÷CH2★, N...C÷CH2★S÷CH2ya, N=C-S-÷CH2★, and substituted or non-containing nitrogen atom represented by R2. Specifically, the substituted -valent hydrocarbon group includes a methyl group,
Alkyl groups such as ethyl, propyl and butyl groups; alkenyl groups such as vinyl and allyl groups; aryl groups such as phenyl, tolyl and xylyl groups; aralkyl groups such as bentyl and phenylmethyl; A group in which some or all of the hydrogen atoms of the group are substituted with halogen atoms, etc., chloropropyl group, chlorophenyl group, 3,3,3
Examples include monotrifluoropropyl group.

Furthermore, × in the formula represents a hydroxyl group or a hydrolyzable atom or group, and this includes a halogen atom such as a chlorine atom,
Alkoxy groups such as methoxy, ethoxy, and propoxy groups; alkoxy-substituted alkyl groups such as 2-methoxyethyl and 2-ethoxycetyl; acyloxy groups such as acetoxy; amino groups, amido groups, aminoxy groups, ketoxime groups, vinyloxy groups, etc. Examples include alkenyloxy groups.

Such nitrogen atom-containing organic poppy or elementary compounds can be synthesized by various methods known from the field, and specific examples of the nitrogen atom-containing organic poppy or elementary compounds include the compounds shown below. can be given.

Day 2 N ÷ CH 2 Wosu Si (Mountain OC 2 Day 5) 3 , (n;
In addition, the alpha cyanoacrylate resin adhesive used in the method of the present invention is conventionally known as an instant adhesive, and specifically, Aron Alpha #101, Aron Alpha # Examples include those known under trade names such as 201 (all manufactured by Toagosei Kagaku Co., Ltd.).

In addition, in consideration of more reliable achievement of the object of the present invention or workability during adhesive bonding, the alpha cyanoacrylate resin adhesive should have a viscosity (25 oo) of 2 to 25 oo.
30,000 centipoise, specific gravity (25℃) 1.05~
It is preferable to use one in the range of 1.12.

Furthermore, the silicone rubber molded product targeted by the method of the present invention is not limited to the molecular structure, production, curing mechanism, liquid type, etc. of the organopolysiloxane as the main component constituting it, and is a conventionally known silicone rubber molded product. It can be applied to various molded products such as dimethylpolysiloxane (MQ), dimethylvinylpolysiloxane (VMQ), etc.
), dimethylvinylphenylpolysiloxane (PVMQ
), 3-trifluoropropylmethylpolysiloxane (F
VMQ) and other polysiloxanes, curing catalysts, crosslinking agents, various fillers, pigments, property improvers (e.g. heat resistance improvers, flame retardant agents, conductivity agents, magnetism agents, heat conductive agents, magnetic flux conductive agents, (fiber powder, foaming agent, etc.), or polysiloxanes whose main component is siloxane radically polymerized with acrylic acid monomers, their esters, styrene, etc. Can be done.

In addition, the objects to be adhered in the method of the present invention include Fe, A
Metals such as I, Ni, Cu, Zn, Cr, Au, Ag, or alloys of these (e.g. stainless steel),
Or those made of plastic materials such as those plated with these metals, polyvinyl chloride, polyester, polycarbonate, polyacetal, polystyrene, ABS resin, AS resin, urea resin, acrylic resin, phenolic resin, nylon, etc. Examples include synthetic rubbers such as natural rubber, chloroprene rubber, butyl rubber, nitrile rubber, styrene-butadiene rubber, butadiene rubber, ethylene-propylene rubber, silicone rubber, and urethane rubber, ceramics, and various fibrous materials.

In the method of the present invention, when bonding a silicone rubber molded article and various adherends as described above, a predetermined amount of a nitrogen atom-containing organic compound or elementary compound is added to the composition constituting the silicone rubber molded article. is added to obtain a silicone rubber molded product, or the compound is uniformly applied to the bonding surface and then joined together using an alpha-cyanoacrylate resin adhesive. When the elementary compound is mixed and added to the composition, the amount used is approximately 0.05 to 10. It is sufficient to use a wide amount%, and when simply applying it to the adhesive surface, it is approximately 0.1 to 10%.
A value of approximately 0/re is sufficient.

According to the present invention, a silicone rubber molded product treated with the above-mentioned nitrogen atom-containing organic poppy compound can be quickly and firmly adhered to an object to be adhered with an alpha cyanoacrylate resin adhesive. , the excellent properties of silicone rubber and the excellent properties of alpha cyanoacrylate resin adhesives such as instantaneous properties, elasticity, one-component property, and low viscosity can be utilized. This has the advantage of making on-site construction possible, which was previously difficult, and allowing the use of compare belts, as well as the use of complex-shaped molded products, large-sized products that cannot be molded without effort, or plastics that are difficult to mold in one piece. Applications of silicone rubber have expanded dramatically, such as the ability to easily create adhesive molded products, etc., and the non-toxicity of silicone rubber has been applied to medical, food-related fields, decorative fields such as glasses and buttons, as well as various automobile parts and electrical appliances. , can be widely applied as electronic components.

Next, the present invention will be explained with reference to Examples, and all parts in each example indicate parts by weight.

Example 1KE951U (product name: VMQ manufactured by Shin-Etsu Chemical Co., Ltd.
), 0.6 part of dicumyl peroxide was added to 100 parts of dicumyl peroxide, and the mixture was compression molded at a pressure of 30 kg/for 1 minute at a temperature of 170 oo, and then heat treated at a temperature of 200 qo for 2 hours to form a sheet with a thickness of 2. was prepared and used as a sample.

Various nitrogen atom-containing organic poppy-element compounds as shown in Table 1 below were directly applied to the surface of this sample (coating amount: 0.5
(W/N) This treated sample was then adhered to an acrylic resin using Aron Alpha #201 (trade name, manufactured by Toagosei Kagaku Co., Ltd.), and the results shown in Table 1 were obtained. Table - 1.Example in which the rubber was destroyed in the adhesive strength test K and the adhesive strength could not be measured 2.Dimethylpolysiloxane 100 with an average degree of polymerization of about 5000 and less than 100 capped with dimethylsilanol groups
A composition consisting of 5 parts of methylhydrodiene polysiloxane and a catalytic amount of a platinum compound is dissolved in toluene, and then 0.2 parts of a nitrogen atom-containing organic compound, an elementary compound, is dissolved in toluene.
Added and blended Japanese.

The same silicone rubber sheet as that used in Example 1 was soaked in the solution and treated, and then 5
A sample was prepared by heat curing for a minute. This sample and plastic sheets made of various materials as shown in Table 2 below were mixed into Aron Alpha #201 (trade name, manufactured by Toagosei Kagaku Co., Ltd.).
The results are shown in Table 2.

Table 2 Example 3 100 parts of KE555U (trade name: VMQ manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed with 0.5 part of a nitrogen atom-containing organic poppy compound as shown in Table 3 below and 0 part of dicumyl peroxide.
．． 6 parts were added and compression molded for 10 minutes under the conditions of a pressure of 30k9/carp and a temperature of 170pm, and then heat treated at 200°C for 2 hours to prepare a sample.

When this sample was adhered to metals of the types shown in Table 3 below using Aron Alpha #101 (trade name, manufactured by Toagosei Co., Ltd.), the results shown in the table were obtained. Table -
3 ○: Full surface adhesion, showing rubber destruction, ×: No adhesion.

Example 4 The silicone rubber molded products treated with the nitrogen atom-containing organic poppy compound used in Examples 1 to 3 were bonded together using Aron Alpha #201 (trade name, manufactured by Toagosei Kagaku Co., Ltd.). However, it showed complete adhesion.
A peel test showed rubber failure.

Claims (1)

[Scope of Claims] 1. When adhesively bonding a silicone rubber molded article and an object to be adhered using an alpha acyanoacrylate resin adhesive, a nitrogen atom-containing organosilicon compound is applied to the silicone rubber molded article in advance. A method for adhesively bonding silicone rubber molded products, characterized by adding or coating on the surface. 2 Nitrogen atom-containing organosilicon compounds have the formula ▲ mathematical formula, chemical formula, table, etc. ▼ (in the formula, R^1 is a monovalent organic group containing a nitrogen atom, R
^2 is a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group that does not contain a nitrogen atom, X is a hydroxyl group or a hydrolyzable atom or group, a, b and c are each 0<
The silicone rubber molded article according to claim 1, which is a silane or siloxane represented by a≦4, 0≦b<4, 0≦c<4, where a+b+c is 0<a+b+c≦4 Adhesive bonding method.