JPH01256579A - Adhesive - Google Patents

Abstract

PURPOSE:To obtain an adhesive improved in adhesiveness to a rubber composition comprising a nonpolar rubber of a low degree of unsaturation and storage stability, by mixing a specified modified ethylene/alpha-olefin copolymer rubber with, optionally, an organic solvent. CONSTITUTION:An ethylene/alpha-olefin copolymer rubber obtained by copolymerizing ethylene (i) with a (desirable) 8-10C alpha-olefin (ii) (e.g., propylene) and, optionally, a nonconjugated diene (iii) is reacted with an acid anhydride (iv) (e.g., maleic anhydride) to obtain an ethylene/alpha-olefin copolymer rubber (a) having 0.1-10wt.% component (iv). Component (a) is reacted with 0.2-2mol, per mol of the acid anhydride of component (a), of a dialkylamine (b) (e.g., diethylamine) in an organic solvent to obtain a modified ethylene/alpha-olefin copoly mer rubber. This rubber is mixed with, optionally, an organic solvent (e.g., toluene).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive suitable for adhering rubber compositions and fibers. More specifically, it is particularly suitable for adhering rubber compositions made of low unsaturation nonpolar rubbers such as ethylene-α-olefin copolymer rubber and isobutylene-isoprene copolymer rubber, and has a low storage stability. It is related to.

Adhesive compositions mainly composed of polymeric materials containing rubber compounds are widely used, but they do not provide satisfactory adhesive strength to all rubber compositions, especially those with low unsaturation levels mentioned above. It did not provide sufficient adhesion to rubber compositions made of polar rubber.

The present inventors have made extensive studies to provide an adhesive suitable for adhering rubber compositions made of these low-unsaturation nonpolar rubbers, and have obtained the invention of Japanese Patent Application No. 1982-19282. He continued to consider the matter.

[Problem to be solved by the invention]

Under such circumstances, the problem to be solved by the present invention is to provide an adhesive made of a modified ethylene-α-olefin copolymer rubber having excellent adhesion to rubber compositions and the like.

Furthermore, another object is to provide adhesives with better storage stability.

[Means for Solving the Problems] That is, the present invention uses acid anhydrides in an amount of 0.1 to 10! The main component is a modified ethylene-α-olefin copolymer rubber obtained by reacting dialkylamine with an ethylene-α-olefin copolymer rubber containing fl percent by 0.2 to 2 times the mole of acid anhydride. The present invention relates to an adhesive characterized by:

Furthermore, the present invention relates to an adhesive comprising the modified copolymer rubber in an organic solvent.

The present invention will be specifically explained below.

(1) The ethylene-α-olefin copolymer rubber in the present invention refers to ethylene α-olefin copolymer and ethylene-α-olefin non-conjugated diene copolymer,
As the α-olefin, those having 8 to 10 carbon atoms are preferably used, and specific examples include propylene, 1-butene 1
Examples include 1-pentene and 1-hexene.

Examples of the non-conjugated diene include dicyclopentadiene, ethylidene norbornene, 1,4-hexadiene, methyltetrahydroindene, and methylnorbornene.

(2) Examples of the acid anhydride of the present invention include maleic anhydride, citraconic anhydride, and nadic anhydride.

The content of acid anhydride in the ethylene-α-olefin copolymer rubber is preferably 0.1 to 10 percent by weight.

The reason why the acid anhydride content is limited to 0.1 to 10% by weight is because below this range, the adhesive strength is low, and above this range, no significant effect of improving the adhesive strength is expected. The preferred range is 0.2 to 8 weight percent;
A more preferred range is 0.5 to 5 weight percent.

In the present invention, a generally known reaction is applied to the reaction between the acid anhydride and the ethylene-α-olefin copolymer rubber.

More specifically, it is manufactured according to, for example, Japanese Patent Publication No. 58-58005, Japanese Patent Publication No. 58-445, etc.

Further, a modified ethylene-α-olefin copolymer rubber containing an alkenyl aromatic monomer such as styrene or methylstyrene and an acid anhydride obtained according to JP-A-62-112614 can also be suitably used.

(8) Examples of the dialkylamine in the present invention include dimethylamine, diethylamine, dipropylamine, diisopropylamine, dibutylamine, diisobutylamine, dialkylamine, di5eC-butylamine, cyamylamine, diakylamine, dioctylamine, etc., but preferably are diethylamine, dipropylamine, and dibutylamine.

The amount of dialkylamine used is ethylene-α containing acid anhydride.
-0.2 based on the amount of acid anhydride in the olefin copolymer rubber
-2 times the mole range, preferably 0.5 to 1.5
It is in the range of twice the mole, more preferably 0.8 to 1.2 times the mole. This is because below this range, the effects of the above on adhesive strength and storage stability are small, and above this range, the adhesive strength decreases.

The reaction of dialkylamine is carried out using ethylene containing acid anhydride.
By dissolving the α-olefin copolymer rubber in a Wim agent, for example, an aromatic hydrocarbon solvent such as toluene, xylene, or ethylbenzene or an aliphatic hydrocarbon solvent such as hexane, heptane, octane, or decane, and simply adding the dialkylamine. However, it is more preferable to carry out stirring under heating.

It is also possible to adjust the concentration and use this solution as a liquid fixing agent.

The thus obtained modified ethylene-α-olefin copolymer rubber can be used as an adhesive without being dissolved in a solvent.

Another embodiment of the present invention is an adhesive comprising the modified ethylene-α-olefin copolymer rubber and an organic solvent, for example, an adhesive in which the modified product is dissolved in an organic solvent. This adhesive exhibits excellent adhesion to rubber compositions, particularly low unsaturation nonpolar rubber compositions, and further provides an adhesive with improved storage stability.

(4) As the organic solvent in the present invention, aliphatic, aromatic, and halogen-containing compound organic solvents are generally used. Specifically, pentane, hexane, cyclohexane,
Examples include benzene, toluene, xylene, ethylbenzene, ethyltoluene, cumene, diethylbenzene, chloroform, and carbon tetrachloride. The dissolved concentration of the modified ethylene-α-olefin copolymer rubber containing acid anhydride is 6
The optimum concentration is selected within the range of 50% by weight depending on the molecular weight of the ethylene-α-olefin copolymer rubber modified product and the method of applying the adhesive.

(5) In the present invention, reinforcing agents, fillers, softeners, adhesives, etc. known in the adhesive industry or rubber industry may be added as necessary.

The adhesive of the present invention exhibits excellent adhesion to rubber compositions, particularly compositions of low unsaturation nonpolar rubbers such as ethylene-α-olefin copolymer rubber and isobutylene-isoprene rubber. Specifically, vulcanization adhesion between an unvulcanized rubber composition and a vulcanized rubber composition, adhesion between vulcanized rubber compositions, and vulcanization adhesion between an unvulcanized rubber composition and natural fibers and/or synthetic fibers. , exhibits excellent adhesion between the vulcanized rubber composition and natural fibers and/or synthetic pongee nonwoven fabric.

Furthermore, the adhesive composition of the present invention can be applied to bonding natural fibers and/or synthetic fibers.

A more specific explanation will be given below according to examples.

〔Example〕

Examples 1-6, Comparative Examples 1-4 Table 1 shows the composition of the adhesive used in Examples and Comparative Examples.

After adding additives using a roll as necessary to the maleic anhydride-containing ethylene-α-olefin copolymer rubber that has been reacted with dialkylamine, a predetermined amount of the organic solvent shown in Table 1 was added, and the mixture was heated at 50°C for 8 hours. Adhesives A to C were obtained by heating for hours and dissolving in an organic solvent.

The adhesive was used for comparison, and an ethylene-α-olefin copolymer was similarly dissolved in an organic solvent.

Table 2 shows the composition of the rubber adherend. Compound A in Table 2 is B
The mixture was kneaded using an R-type Banbury, and compounding agent B was added to this mixture using a Binφ roll, and the resulting unvulcanized rubber composition was press-vulcanized under the vulcanization conditions shown in Table 2. A vulcanized sheet measuring 150 x 15 g x 2 m was obtained. Using a punching blade from this sheet, 20 fl x 150 ff
A strip-shaped test piece was prepared.

The fiber adherend was prepared by cutting a woven fabric into strips of 40 ff x 200 m. Adhesives A to D shown in Table 1 are uniformly applied to a strip-shaped test piece of a vulcanized rubber adherend using a glass rod, and in the case of two vulcanized rubber adherends, the adhesives A to D shown in Table 1 are left for 80 minutes after application. The adhesive-coated surfaces of the test pieces were bonded together. The vulcanized rubber adherend and the fiber adherend were bonded together immediately after the adhesive was applied.

Thereafter, a hand roller of 2 kq was made to reciprocate 8 times to bring it into close contact, and the material was cured under the conditions shown in Table 8 under no load.

Vulcanized Rubber Adherent-A In the case of a thin wave adhered object, after curing, the protruding fiber adherend was cut with scissors to the same size as the strip-shaped test piece of vulcanized rubber.

The adhesive strength of these adhesive bodies was measured by performing a 180° peel test at a tensile rate of 50 M/min in accordance with JIS K2SO3.

The results are also shown in Table 8.

Examples 7 to 10, Comparative Examples 5 to 6 Unvulcanized rubber compositions of EPDM compositions A and B shown in Table 2 were prepared into sheets with a thickness of 2 fl using a 3 inch φ roll. It was cut into a size of 150 x 150 fl and used as a test piece. The adhesives in Table 1 were applied to specimens of unvulcanized rubber compositions. Unvulcanized rubber composition adherend - In the case of a vulcanized rubber composition adherend, it was applied and left for 80 minutes, and then an adhesive was applied and left for the same time.150X150X2 as described in Example 1
A vulcanized rubber composition sheet of ff was attached. In the case of the unvulcanized rubber composition adherend - IIA fiber adherend, a woven fabric measuring 150 x 150 m was bonded together immediately after application. In each case, a 2 kg hand roller was moved back and forth 8 times to bring them into close contact. Vulcanization was carried out at 160° C. for 80 minutes in pressurized air at 9 f/d. It was punched out into a rectangular shape of 20×1501jl using a punching blade. This strip-shaped test piece was rated according to JIS K680.
1, a 180° peel test was conducted at a tensile rate of [)ff to measure the adhesive strength. The results are shown in Table 4.

Examples 11 to 18, Comparative Examples 8 to 9 A woven fabric was cut into a size of 150 x 150 m, and the adhesive shown in Table 1 was applied uniformly with a glass rod.
Woven fabrics of 0x150sm were bonded together and cured under the curing conditions shown in Table 5. 20X150f using a punching blade
A rectangular test piece of i was prepared.

180 at a tensile rate of 50fl for this strip-shaped test piece.
A peel test was conducted to measure the adhesive strength. The results are also shown in Table 6.

Examples 14-15, Comparative Examples 10-11 The storage stability of the adhesive before and after the dialkylamine reaction was investigated. Table 6 shows the composition of the adhesive and the results of the study.

Storage stability was measured by placing 20Of the adhesive in a 500 l Erlenmeyer flask with a stopper, and observing changes in appearance such as the presence of precipitates and cloudiness after leaving it indoors for 80 days, and changes in solution viscosity at 25°C. It was done by

〔Effect of the invention〕

The present invention provides an adhesive mainly composed of a modified ethylene-α-olefin copolymer rubber having excellent adhesive strength and improved storage stability.

Claims (2)

[Claims] (1) Ethylene-α- obtained by reacting an ethylene-α-olefin copolymer rubber containing 0.1 to 10% by weight of acid anhydride with dialkylamine in a molar ratio of 0.2 to 2 times the amount of acid anhydride. An adhesive characterized in that the main component is a modified olefin copolymer rubber. (2) An adhesive comprising the modified ethylene-α-olefin copolymer rubber according to claim 1 and an organic solvent.