JPH066698B2 - adhesive - Google Patents

Description

TECHNICAL FIELD The present invention relates to an adhesive, and more particularly to an adhesive having improved adhesiveness.

[Prior art and its problems] Conventionally, an alkali neutralized product of an isobutylene-maleic anhydride binary copolymer or a composition obtained by blending this neutralized product with an inorganic filler can be used as an adhesive. It has been known.

Isobutylene-maleic anhydride binary copolymer, which is the material for this adhesive, can be produced relatively easily in the presence of a radical generator, but since it is an extremely hard polymer, it is suitable for treatment using alkali. It required harsh conditions. Also,
An adhesive obtained by blending the alkali-neutralized product with an inorganic filler such as calcium hydroxide has not yet exhibited sufficient adhesive force.

The present invention has been made based on the above circumstances.

That is, an object of the present invention is to provide an adhesive that does not require harsh conditions for alkali treatment and has a large adhesive force, even though it is an adhesive based on an isobutylene-maleic anhydride type copolymer. It is in.

In order to achieve the above-mentioned object, as a result of earnest research by the present inventor, a terpolymer of α-olefin, maleic anhydride or a derivative thereof and a vinyl compound (provided that isobutylene-maleic anhydride-vinyl acetate or acryl is used). Alkali treatment of methyl acid terpolymer can be performed under mild conditions, and the terpolymer (provided that isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer is used). The inventors of the present invention have found that a mixture of an alkali neutralized product (excluding the above) and an inorganic filler exerts great adhesiveness and arrived at the present invention.

[Means for Solving the Problems] Means of the present invention for solving the above problems include an α-olefin-maleic anhydride or a derivative thereof-vinyl compound terpolymer (however, isobutylene-maleic anhydride). An adhesive comprising an alkali-neutralized product of an acid-vinyl acetate or a methyl acrylate terpolymer) and an inorganic filler.

It should be noted in the present invention that a terpolymer of α-olefin, maleic anhydride or a derivative thereof, and a vinyl compound is used as a base polymer of an adhesive (provided that isobutylene-maleic anhydride-vinyl acetate or acrylic acid is used). Alkali-neutralized products (excluding methyl terpolymer) are used. This terpolymer (however, excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) can be easily alkali-treated and is based on its alkali-neutralized product. Surprisingly, it is possible to obtain an adhesive that exerts a great adhesive force. Therefore, this terpolymer of α-olefin, maleic anhydride or its derivative, and a vinyl compound (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) will be described in more detail. I will describe.

Examples of the α-olefin include ethylene, propylene, isobutylene, α-butylene, pentene-1 and the like.

As the derivative of maleic anhydride, for example, maleic acid, methyl maleate, ethyl maleate, maleic acid monoester such as propyl maleate, dimethyl maleate, diethyl maleate, dipropyl maleate,
Methyl ethyl maleate, methyl propyl maleate,
Examples include maleic acid diesters such as ethylpropyl maleate.

Examples of the vinyl compound include styrene, α-methylstyrene, vinyl acetate, acrylic acid, methyl acrylate, ethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, acrylamide, vinyl chloride and the like.

As the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) in the present invention, various terpolymers of the above-mentioned three kinds of monomers are conceivable, A preferred terpolymer is a terpolymer of isobutylene, maleic anhydride and styrene or methyl methacrylate.

The terpolymer of the present invention (however, excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) is the α-olefin, the maleic anhydride or a derivative thereof, and the vinyl compound. Can be obtained by copolymerizing by various methods,
Usually, it can be preferably produced by the following method.

That is, the charging ratio of the monomer as a raw material is not particularly limited, and the target terpolymer (provided that isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer is excluded. It can be appropriately determined in consideration of the physical properties of the above). Usually, the charging ratio of maleic anhydride or its derivative is 0.5 to 3.0 mol, preferably 1.0 to 2.0 mol, relative to 1 mol of α-olefin such as isobutylene, vinyl compound such as styrene and methacryl. The charging ratio of methyl acid or the like is 0.01 to 1.5 mol, preferably 0.05 to 1.2 mol.

Further, a catalyst can be used in the copolymer, and usually, a peroxide such as benzoyl peroxide, lauroyl peroxide, cumene peroxide, t-butyl hydroperoxide, dicumyl peroxide, azobisisobutyrate. Examples thereof include azo compounds such as ronitrile and persulfates such as potassium persulfate. The amount of the catalyst used is 0.01 to 10 parts by weight, preferably 0.05 to 100 parts by weight of all the monomers.
~ 5 parts by weight. The catalyst can be used as it is or after being diluted and dissolved in a solvent. As for the timing of addition, all may be added at the beginning of the weight, or may be added dividedly during the polymerization.

Next, various solvents can be used for the copolymerization reaction. For example, when the copolymerization reaction is carried out by a precipitation polymerization method, an isopropyl acetate group, ethyl acetate or the like can be used as the solvent. In this case, the produced terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) does not dissolve in the solvent but precipitates outside the copolymerization reaction system. On the other hand, when the copolymerization reaction is carried out by the solution polymerization method,
N, N-dimethylformamide, dimethyl sulfoxide, acetonitrile, nitromethane, nitroethane and the like can be used as the solvent. In this case, the resulting terpolymer (however, isobutylene-maleic anhydride-
Vinyl acetate or methyl acrylate terpolymers) are dissolved in the solvent. The latter solvent such as N, N-dimethylformamide is preferable in consideration of the reaction progress rate and the productivity of the copolymer.

Whatever method is used for the copolymerization reaction conditions using the raw material monomer, the catalyst and the solvent, the reaction temperature is 30 to 200 ° C., preferably 45 to 150 ° C., and the reaction pressure is atmospheric pressure to 30 kg / cm ^2. G, preferably normal pressure to 1
0 kg / sm ² G, 0.5 to 20 hours, preferably 1 to 10 hours per reaction time are suitable. Then, a ternary copolymer (provided that the isobutylene-maleic anhydride-vinyl acetate or methyl acrylate ternary copolymer is used in the present invention is subjected to a usual post-treatment such as removal of a solvent and unreacted raw material monomers. Excluding coalescence).

The resulting terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) has a number average molecular weight of 3,000 to 400.
000, preferably about 5000 to 200,000. Further, as the repeating unit, α-olefin: maleic anhydride or its derivative: vinyl compound = 1: 0.
It is 5 to 3.0: 0.01 to 1.5 (molar ratio), preferably 1: 1.0 to 2.0: 0.05 to 1.2 (molar ratio).

The adhesive of the present invention is obtained by subjecting the terpolymer obtained as described above (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) to alkali neutralization treatment. It is important to use the alkali neutralized product obtained. By the alkali neutralization treatment, maleic anhydride or its derivative unit in the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) forms a salt. .

Here, as the alkali used, sodium hydroxide, sodium carbonate, ammonium carbonate, ammonia,
Organic amine, sodium acetate, ammonium acetate, urea, thiourea, sodium silicate and the like can be mentioned. Among these, sodium hydroxide and ammonium hydroxide are preferable. The alkali neutralization treatment is usually performed using the above-mentioned alkali aqueous solution. If the neutralization degree is 1 when the amount of alkali is completely neutralized, the neutralization degree is 0.3 to
An amount of 1.0 is used.

The conditions for the alkali neutralization treatment are generally a temperature of 20 to 150 ° C., preferably 50 to 100 ° C. and a pressure of 0.
˜5 Kg / cm ² G, preferably 0 to ² Kg / cm ² G, the treatment time in the above temperature range and pressure range is 10 minutes to 20 hours,
It is preferably 0.5 to 10 hours.

The adhesive of the present invention comprises a mixture of the ternary copolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) with an alkali filler and an inorganic filler. Can be obtained by

The mixture is an alkali neutralization treatment when the alkali neutralization treatment of the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) is an aqueous alkali solution. It is carried out by adding the inorganic filler to an aqueous solution containing a neutralized product of a ternary copolymer (excluding isobutylene-maleic anhydride-vinyl acetate or a methyl acrylate terpolymer) afterwards. be able to. Further, the inorganic neutralized product may be mixed with the inorganic filler after the alkaline neutralized product is separated from the aqueous solution containing the alkaline neutralized product. In this case, in order to adjust the viscosity of the adhesive, water may be added to the mixture of the alkali-neutralized product and the inorganic filler.

As the inorganic filler, for example, oxides, hydroxides, carbonates, sulfates of calcium, magnesium, zinc, barium, cadmium, lead, copper, aluminum, iron and the like,
Examples thereof include sulfite and silicate. Specifically, for example, alumina, iron oxide, zinc oxide, magnesium oxide, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, calcium carbonate, magnesium carbonate, dolomite, calcium sulfate, barium sulfate, calcium sulfite, talc, Clay, mica, asbestos,
Examples thereof include glass fiber, calcium silicate, montmorillonite, bentonite and the like. Among these various inorganic fillers, calcium hydroxide is preferred.

The blending amount of the inorganic filler is 1000 parts by weight or less with respect to 100 parts by weight of the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer). And preferably not more than 500 parts by weight.

The adhesive of the present invention is obtained by mixing the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) and the inorganic filler. However, it is preferable to incorporate rubber latex as an adhesion aid.

As the rubber latex, both natural rubber latex and synthetic rubber latex can be used, but synthetic rubber latex is preferred. Among the latexes of synthetic rubber, the latex of ABA type copolymer rubber having polystyrene block A and polybutadiene block or polyisoprene block B is preferable.

The amount of the rubber latex compounded is 100 weights in total of the alkali-treated terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) and the inorganic filler. Generally, the solid content is 1000 parts by weight or less, preferably 10 to 5 parts by weight.
It is 00 parts by weight.

In the present invention, in order to improve the adhesive strength of the adhesive, a compound having one or more functional groups such as epoxy group, hydroxyl group, amino group and imino group may be blended.

Examples of the compound having an epoxy group include glycerin diglycidyl ether, glycerin triglycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ale, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ale, neopentyl glycol diglyceride. Glycidyl ether and trimethylolpropane polyglycidyl ale are suitable.

Examples of the compound having a hydroxyl group include ethylene glycol, triethylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexane. Suitable are diol, glycerin, pentaerythritol, polyethylene glycol, polypropylene glycol, polyvinyl alcohol and the like.

As the compound having an amino group, diamines such as ethylenediamine, trimethylenediamine, tetramethylenediamine and hexamethylenediamine are preferable.

Examples of the compound having an imino group include ethyleneimine, 2-methylethylimine, 2-ethylethyleneimine, 2,3-dimethylimine, 2,2-dimethylethyleneimine, 2-phenylethylimine and N-methyl. Ethyleneimine and the like are preferable.

The blending amount of the various compounds can be appropriately determined depending on the type of the compound, for example, the blending amount of glycerin diglycidyl ether, the terpolymer (however,
(Excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) functional groups,
Usually, 0 to 100 mol%, preferably 10 to 50 mol%
Is.

The adhesive of this invention is prepared by adding the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer), the inorganic filler, the rubber latex and the functional group. In the case of being composed of a compound having, there is no particular limitation on the mixing order of the respective components, but with the terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer). It is preferable to blend the rubber latex and the compound having the functional group in a mixture with the inorganic filler.

The adhesive according to the present invention is preferably used for adhering paper, wood, plastics and the like. It is also suitable as a rewetting adhesive for stamps, stamps, etc., and also suitable for bonding plywood, laminated wood, etc.

EFFECT OF THE INVENTION According to the present invention, α-olefin-maleic anhydride or its derivative-vinyl compound terpolymer (provided that
(Although isobutylene-maleic anhydride-vinyl acetate or a methyl acrylate terpolymer is excluded), an alkali-neutralized product is used.
It is possible to provide an adhesive having a high adhesive strength, particularly a split adhesive strength. Further, the terpolymer in the present invention (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) does not require harsh conditions for alkali neutralization treatment, The neutralization process can be easily performed.

EXAMPLES Next, the present invention will be described more specifically by showing Examples and Comparative Examples of the present invention. Needless to say, the present invention is not limited to this embodiment.

(Example 1) 60 g of maleic anhydride, 31.8 g of styrene, 0.6 g of benzoyl peroxide and 460 cc of acetonitrile were placed in a 1 liter autoclave, and sufficiently cooled and deaerated.

Then, 37 g of isobutylene was added, and the polymerization reaction was carried out at 110 ° C. for 2 hours while stirring at 400 rpm.
After completion of the reaction, the polymerization reaction product was put into water to obtain an isobutylene-maleic anhydride-styrene terpolymer. This product has a number average molecular weight of 93,000, a density of 1.23 g / cm ³ ,
The acid value was 526 mg · KOH / g.

25 g of the obtained terpolymer was added with sodium hydroxide 9.4.
was charged into a 1 liter glass autoclave together with an alkaline aqueous solution in which 132 g of water was dissolved, and the mixture was heated at 90 ° C. for 6 hours.
The alkali neutralization treatment was performed with stirring for an hour. In this way, the concentration of the terpolymer is 15% by weight and the degree of neutralization is 1.
An aqueous solution of alkali neutralized product of 0 was obtained.

25 g of calcium hydroxide and styrene-butadiene copolymer rubber latex (solid content 50% by weight) 50
g was added and mixed to obtain an adhesive.

The split adhesive strength (Kg / inch) of this adhesive is determined by JIS
It measured and evaluated based on K6853. The test piece is 25
It was prepared by using a birch tree of × 300 × 4 mm as an adherend.

The results are shown in Table 1.

Example 2 105 g of isobutylene-maleic anhydride-methyl methacrylate terpolymer was prepared in the same manner as in Example 1 except that 30.6 g of methyl methacrylate was used instead of 31.8 g of styrene. Obtained. The number average molecular weight of this product is 370.
00, density 1.25 g / cm ³ , acid value 567 mgKOH /
It was g.

Except for using an alkaline aqueous solution obtained by dissolving 10.1 g of sodium hydroxide in 132 g of water, 25 g of the ternary copolymer was subjected to an alkali neutralization treatment in the same manner as in Example 1 above so that the concentration of the ternary copolymer was An aqueous solution of the alkali-treated product having a neutralization degree of 1.0 at 15% by weight was obtained.

Using this aqueous solution, an adhesive was obtained in the same manner as in Example 1, and the split adhesive strength was measured and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Comparative Example 1) 60 g of maleic anhydride, 37 g of isobutylene, 0.8 g of benzoyl peroxide and 460 cc of n-hexane were charged into a 1 liter autoclave, and sufficiently cooled and deaerated. Then, a copolymerization reaction was performed at 110 ° C. for 2 hours with stirring, and the solvent was further distilled off to give a number average molecular weight of 2700.
The acid value was 0 and the acid value was 729 mg · KOH / g.

50 g of the obtained copolymer was charged into a 1 liter glass autoclave together with an alkaline aqueous solution in which 26 g of sodium hydroxide was dissolved in 257 g of water, and an alkali neutralization treatment was performed while stirring at 98 ° C. for 10 hours. In this way, an aqueous solution of an alkali-neutralized terpolymer having a terpolymer concentration of 15% by weight and a degree of neutralization of 1.0 was obtained.

An adhesive was obtained from this aqueous solution in the same manner as in Example 1, and its split adhesive strength was measured and evaluated.

The results are shown in Table 1.

As shown in Table 1, an adhesive having an alkali-neutralized terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer) and an inorganic filler. The split adhesive strength of the agent is much higher than that of an adhesive having an alkali neutralization product of a binary copolymer and an inorganic filler.

Claims (1)

[Claims] 1. Alkaline neutralization of α-olefin-maleic anhydride or its derivative-vinyl compound terpolymer (excluding isobutylene-maleic anhydride-vinyl acetate or methyl acrylate terpolymer). An adhesive characterized by having a substance and an inorganic filler.