JPS5946781B2 - Method for manufacturing adhesive composites - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a rubber adhesive composite with excellent adhesive strength.

More specifically, as an adhesive, 1.2-polybutadiene (hereinafter referred to as 1. 2-polybutadiene), such as ethylene-propylene rubber (EPM), ethylene-propylene rubber (EPM),
Related to thermal bonding of rubber adherends obtained from olefin hydrocarbon rubber such as propylene-diene terpolymer rubber (EPDM) or conjugated diene hydrocarbon rubber such as styrene-butadiene rubber (SBR) It is. Because EPM and EPDM have excellent properties such as weather resistance and heat resistance, they are playing an important role in various fields, but when applying these EPM and EPDM to various fields, adhesives are often required. be. However, the adhesives on the market today are EPM, E
There are almost no materials that can be said to have sufficient adhesive strength to PDM, and it is no exaggeration to say that it is almost impossible to produce an adhesive composite that has adhesive strength sufficient for practical use. EPM and EPDM are also used to improve the weather resistance, heat resistance, etc. of other rubbery polymers, such as SBR, polybutadiene rubber (BR), polyimprene rubber (IR), natural rubber, butyl rubber (IIR), etc. Although they are often used in blends with these polymers, it is well known that compositions containing such EPM and EPDM also have very poor adhesive properties, which poses problems when producing adhesive composites. This is where I am. As a result of extensive studies while keeping these points in mind, the inventors found that E.
In producing an adhesive composite of a rubber adherend containing PM or EPDM alone or containing them, specific 1.2-
It has been found that an adhesive composite with excellent adhesive strength can be obtained in a simple process by thermally bonding using polybutadiene having a high binding structure content, crystallinity, and intrinsic viscosity.

Furthermore, in addition to EPM or EPDM, for example, SBR
, at least one of conjugated diene-based hydrocarbon rubbers such as BR
It was discovered that a rubber adherend obtained from seeds can be similarly thermally bonded using the polybutane diene, and based on these findings, the present invention was achieved. That is, in the present invention, when adhering rubber adherends obtained from at least one type of olefin-based or diene-based hydrocarbon rubber, an adhesive having 1.2-bond structure of 70% or more and a crystallinity of 10% is used as an adhesive. % or more, and the intrinsic viscosity [η] (measured in toluene at 30°C) is 0.
This is a method for producing an adhesive composite, which uses polybutadiene having a molecular weight of 7 or higher and heat-treats the polybutadiene at a temperature higher than the softening point of the polybutadiene.

The 1,2-polybutadiene used as the adhesive in the present invention has a 1.2-bond structure of 7001) or more, preferably 85qf) or more, and a crystallinity of 10 (:f).
The above value is preferably 15 to 50 (f), and the intrinsic viscosity [η] measured at 30° C. in toluene is 0.7 or more.

1.2 If the bond structure, crystallinity, and intrinsic viscosity are smaller than these, the desired effects of the present invention cannot be sufficiently obtained.

This 1,2-polybutadiene exhibits a sufficient effect as an adhesive when used alone, but if necessary, reinforcing agents and
Additives such as fillers, softeners, adhesives, anti-aging agents, vulcanization aids, and vulcanization accelerators may also be used.

Furthermore, by blending commonly used crosslinking agents such as sulfur, peroxides, quinoids, and phenolic resins, 1,2-polybutadiene can be cured simultaneously with the heat treatment for adhesion, thereby making it possible to cure the adhesive layer. It is expected that adhesive composites with low temperature dependence and that can withstand use even at high temperatures can be produced. The 1,2-polybutane diene used as the adhesive is preferably used in the form of a film or sheet, but it can also be used after being dissolved in a solvent such as benzene, toluene or hexane.

On the other hand, the rubber adherend to be bonded using such 1,2-polybutadiene is obtained from olefin-based or diene-based hydrocarbon rubber. EPM, . EPDM,. IIR etc. are used, but
Preference is given to EPMsEPDM or mixtures thereof with IIR. Also, as a diene hydrocarbon rubber, SBRl
2BRl natural rubber, IR, etc. can be used as a diene hydrocarbon rubber, but polypentenamic rubber obtained by ring-opening polymerization of cyclobenzene can also be used as the diene hydrocarbon rubber.
Especially SBR,. BRl natural rubber, IR is preferred. Of course, these rubbers can also be used as a mixture of two or more.
A compound containing reinforcing agents, fillers, softeners, adhesives, vulcanization aids, vulcanization accelerators, crosslinking agents, anti-aging agents, etc. commonly used in such rubbers may be used as is or by a conventional method. The cured vulcanizate is used as an adherend. When the compound is used as an adherend, vulcanization and adhesion can be performed simultaneously. Further, the adherends may be of the same type or may be used in an appropriate combination of different types.

In the present invention, the adhesive composite is obtained by inserting 1,2-polybutadiene into the adhesive surface of the rubber adherend obtained as described above,
It is produced by heat-treating the 1,2-polybutadiene at a temperature equal to or higher than its softening point. There are no particular restrictions on the method of heat treatment, and it can be easily carried out by conventional methods such as various hot presses. As described above, according to the method of the present invention, a rubber adhesive composite with excellent adhesive strength can be easily obtained by a simple method.

The present invention will be explained in more detail below using practical examples, but the present invention is not limited to these examples unless it exceeds the gist thereof.

Example 1 The adherend was mixed by a conventional method according to the compounding recipe shown in Table 1, and the kneaded rubber compound was mixed in a size of 17 mm in length x width x thickness.
CT71×17CTL×0.2cm. 16 in the mold of
It was created by condensation vulcanization at 00C for 20 minutes.

The adhesive 142-polybutadiene used was polybutadiene having the properties shown in Table 2, and it was taken out as a sheet with a thickness of 0.5 or more from rolled soil at 80 to 90°C and subjected to a test.
For the adhesion test sample, the 1.2 polybutadiene sheet was sandwiched between the adherends in the form of a sandwich, and the sheets were pressed together at a temperature of 160° C. under a load of 1 kg/CTl for 3 minutes.

Width of the sample after cooling: 14 cm. It was punched out into a strip shape with a length of 15 crn, and tested in accordance with JIS K63Ol Section 7. Method of Preparation of Example Adherent The adherend was prepared in the same manner as in Example 1I according to the formulation shown in Table 4.

Method for Preparing Adhesive 142-Polybutadiene was prepared using the A type shown in Table 2 in the same manner as in Example 1.

Method for preparing sample for adhesion test and method for peeling test The same method as in Example-1 was used. Example I Method of Preparation of Adherent The adherend was prepared in the same manner as in Example I according to the formulation shown in Table-6.

Method for Preparing Adhesive Adhesive 1, 2 Polybutadiene was prepared in the same manner as in Example 1 using Type A shown in Table 2.

Method for preparing sample for adhesion test and method for peeling test The same method as in Example-1 was used.

Good adhesion is also shown in blended vulcanizates of EPDM and other rubbers.

Method for Preparing Adherents of Examples The adherends were mixed in a conventional manner according to the composition shown in Table 8, and the mixed mixture was taken out as a 3 m/m thick sheet using rolled soil and subjected to a test.

Adhesive Preparation Method 1.2 Polybutadiene was prepared in the same manner as in Example 1 using Type A shown in Table 2.

How to create a sample for adhesion test For the sample for adhesion test, sandwich 1.2 polybutadiene as an adhesive between adherends in a sandwich shape, length x width x thickness 1
16'' in a mold of 0cm x 10C711 x 0.6mm
The adherend was vulcanized by pressure bonding with C2O for a minute, and at the same time, the adherend was bonded with 1,2 polybutadiene.

Peeling test method It was carried out in the same manner as in Example-1.

Claims (1)

[Scope of Claims] 1. As an adhesive on the bonding surfaces of rubber adherends obtained from one or more olefin-based or diene-based hydrocarbon rubbers, 1.2-bond structure is 70% or more and crystallinity is 10. % or more, the intrinsic viscosity [η] (measured in toluene at 30°C) is 0.7
A method for producing an adhesive composite comprising applying the polybutadiene described above and heat-treating the polybutadiene at a temperature equal to or higher than the softening point of the polybutadiene.