JPS588771A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide an adhesive compsn. having high initial bonding power, prepared by adding a specified compd. to an alpha-cyanoacrylate. CONSTITUTION:The adhesive compsn. is prepared by adding to an alpha-cyanoacrylate about 0.5-20wt% polyhydric alcohol (deriv.) (e.g., ethylene glycol or methylcellosolve) or polyether compd. with repeating units of formulaI(where X1 and X2 are each H, halogen, hydroxyl, alkyl, aryl, etc.; p is 1 or higher; q is 2 or higher) (e.g., polyalkylene glycol/formaldehyde condenstate) and about 0.0001- 0.5wt% polyhydroxybenzene of formula II (where r is 2 or 3; at least two hydroxyl groups are vicinal) (e.g. pyrogallol) or carboxylic acid (ester) of formula III (where A is H, a hydrocarbon residue or a residue of a heterocyclic compd.; R1 is a hydrocarbon residue; e is 1 or higher; f is 0 or higher) (e.g. lactic acid or gallic acid).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an α-cyanoacrylate adhesive, and its purpose is to improve the initial adhesive strength, especially to adherend materials that are difficult to adhere to with conventional α-cyanoacrylate adhesives. The goal is to improve initial adhesive strength.

α-Cyanoacrylate is extremely susceptible to anionic polymerization, and has the property of polymerizing and curing in a short time without adding a catalyst or heating due to anionic active species such as solid surfaces, moisture in the air, and alkali substances. Therefore, it is widely used as an instant adhesive for bonding rubber, plastic, metal, glass, etc.

However, even though it is an instant adhesive, conventional α-cyanoacrylate adhesives have difficulty adhering to materials such as wood, chrome plating, nickel plating, and polyester (F).
When adhering adherends such as RP) and Bakelite, the initial adhesive strength is somewhat low, and there are restrictions on the use of adhesives that require short-time work, so improvements in the initial adhesive strength are strongly desired. There is.

The present inventors have previously investigated the improvement of the initial adhesive strength of α-cyanoacrylate-based adhesives, and have developed α-cyanoacrylate with the following formula [■] [■] 3- [In the formula, X is a hydrogen atom or a methyl Group and Aya are hydrogen atoms,
A methyl group or a cyano group, X5 is a hydrogen atom, and R2 or R2C0 (R2 represents a hydrocarbon residue including an anionic polymerizable group). However, when X4 is a cyano group, it is excluded that X5 is a hydrogen atom.

1, mXn is an integer, (7?+m)≧1, n≧1.

] and a polyether compound represented by pyrogallol, represented by the following formula [V] (wherein R3 is a hydrogen atom or a substituted or unsubstituted hydrocarbon residue, and h is an integer of 2 or more). By blending it with polyhydroxycarboxylic acid, the objective was achieved and a patent application was filed. (Japanese Patent Application No. 54-173813 and Japanese Patent Application No. 56-54631) In the previous invention, α-cyanoacrylate, pyrogallol or polyhydroxycarboxylic acid,
This method is characterized by the combination of α-cyanoacrylate and a specific polyalkyl ether compound having a functional group that can be copolymerized. If a polyphenol or/and a polycarboxylic acid is used, it is not necessary to specifically copolymerize one of the polyalkyl ethers and α-cyanoacrylate, and even if the polyphenol is a specific alcohol or its ester, it is not necessary to copolymerize it with the prior invention. The present invention was completed by discovering that the initial adhesive strength can be improved without losing the stability and strength of the conventional α-cyanoac IJ L/-).

That is, the present invention provides α-cyanoacrylate with (1) a polyhydric alcohol or a derivative thereof, still having the formula [■] (wherein x1 and x2 are a hydrogen atom, a 710gen atom, a hydroxyl group, a substituted or unsubstituted alkyl group, an arregnyl Xl and X2 may be the same or different. p is an integer of 1 or more, q is an integer of 2 or more, and the terminal may be ring-formed.

), and (2) a compound selected from the group of compounds having the repeating unit of the formula [) %formula%) (in the formula, r is 2 to 3, and at least two hydroxyl groups are in adjacent positions). ), or a polyhydroxy compound represented by the formula [■] (HOOC9-M C0OR+)f Cm ] (wherein A is a hydrocarbon residue i substituted or unsubstituted with only one hydrogen atom
or a heterocyclic compound residue, R1 represents a substituted or unsubstituted hydrocarbon residue, an integer of e≧1, and an integer of f≧0. When A has two or more phenolic hydroxyl groups, e=o may be satisfied only when f≧1. Further, the polyhydric carboxylic acid may be ring-closed to become an anhydride. ) is an α-cyanoacrylate-based adhesive composition, which is blended with a compound selected from the group of carboxylic acids and esters represented by the following. However, the case where the following compounds (3) and (4) are combined with α-cyanoacrylate is excluded from the present invention.

(3) Formula [■] HC=C-C-0←CH2~CH2-0 margin H2-CH
-0 Fuku9 (indicates a hydrocarbon residue that does not contain any groups). However, when X4 is a cyano group, it is excluded that X5 is a hydrogen atom.

1! Xm and n are integers, and (I!+m)≧11n≧1. ] and (4) pyrogallol or a polyether compound represented by the formula [■] (wherein R3 is a hydrogen atom or a substituted or unsubstituted hydrocarbon residue, and h is an integer of 2 or more). 7- Polyhydroxycarboxylic acid.

The α-cyanoacrylate used in the present invention has the general formula [
In the formula, R4 is substituted or unsubstituted alkyl, alkenyl,
Aryl, cyclohexyl, etc. are included, and specifically, for example, methyl, ethyl, n-, i-propyl, n-,
i-,5ec-butyl, pentyl, hexyl, octyl, ethylhexyl, dodecyl, allyl, propargyl, methoxyethyl, ethoxyethyl, terahydrofurfuryl, benzyl, phenyl, chloroethyl, cyclohexyl, trifluoroethyl, etc. These α−
The cyanoacrylate is not limited to one type, but two or more types can also be used in combination.

Examples of polyhydric alcohols to be blended with α-cyanoacrylate in the present invention include ethylene glycol, propylene glycol, tetramethylene glycol, hexamethylene glycol, O-8-crimethylene glycol, polybutadiene diol, and talolpropylene glycol. , 3-methylpencundiol, 2,2-diethylpropanediol, 2-ethyl-
1,4-pucundiol, chrycerin, trimethylolmethane, trimethylolethane, trimethylolpropane, 1,2.6-hexane? derivatives thereof include alkyl, alkenyl, aryl and aralkyl ethers or esters thereof, specifically, for example, methyl cellosolve, ethyl cellosolve, ethylene glycol-n-
Butyl ether, ethylene glycol phenyl ether, ethylene glycol benzyl ether, propylene glycol methyl ether, tetramethylene glycol propyl ether, ethylene glycol diethyl ether, ethylene glycol acetate, ethylene glycol monophrate, ethylene glycol monostearate, ethylene glycol distear Examples include, but are not limited to, ester, ethyl cellosolve stearate, chrycerin monolacrate, glycerin monostearate, sorbicun monolaurate, cellosolve acrylate, cellosolve methacrylate, cellosolve crotonate, and the like.

In the present invention, the formula [
■) Compounds having repeating units of X and X
2 is as described above, but it may be the same or different, and Xl and/or X2 in the repeating unit of p, furthermore, Xl and/or The same or different X2 can be used. In the formula, p means a repeating carbon main chain in the main chain skeleton, and q shows a repeating unit of polyether.

When p=1, the skeleton is a methylene group or a substituted methylene group, and when p≧2, the skeleton is an ethylene group, a trimethylene group, a polymethylene group, or a substituted polyethylene group thereof, but in the present invention, preferably p is 2-6. Further, a preferable range of q is about 2 to 3,000, and if it exceeds this value, especially 10,000 or more, the compatibility with α-cyanoacrylate becomes poor and a uniform composition cannot be obtained.

The polyether compound having a repeating unit of the folded formula [■] may form a ring structure, and includes, for example, crown ethers.

In the present invention, the formula [
Specific examples of compounds having the repeating unit ((ii)) include the following compounds, but are not limited thereto.

Formaldehyde condensates, acetaldehyde condensates, trioxane polymers, polyalkylene glycols (e.g. diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polytetramethylene oxide, poly 3,3-bis(chloro) methyl) butylene oxide, poly 1,3-dioxolane,
Ethylene oxide-propylene oxide block polymer, etc. ), polyalkylene glyco-/l/ monoesters (e.g. methyl calpitol, calpitol, diethylene glycol-n-butyl ether, diethylene glycol phenyl ether, diethylene glycol benzyl ether, dipropylene glycol ethyl ether, tripropylene glycol methyl ether, polyethylene glycol Methyl ether, polyethylene glycol propyl ether, polyethylene glycol methyl ether, polyethylene glycol stearyl ether, polyoxyethylene nonylphenyl ether, polyethylene glycol allyl ether, etc.

), polyalkylene glycol diethers (e.g., diethylene glycol diethyl ether, diethylene glycol di-n-butyl ether, triethylene glycol dimethyl ether, tetraethylene glycol distearyl ether, polyethylene glycol dimethyl ether, etc.), polyalkylene glycol monoesters ( For example, diethylene glycol monoethyl ester,
Tetraethylene glycol methyl ester, tripropylene glycol-n-butyl ester, polyester f L/
Polyethylene glycol methyl ester, polyethylene glycol ethyl ester, polyethylene glycol methyl ester, polyethylene glycol methyl ether, polyethylene glycol stearate, polyethylene glycol oleate, polyoxyethylene sorbitan monolaflate, diethylene glycol acrylate, diethylene glycol methacrylate, diethylene glycol crotonate Such. ), polyalkylene glycol diester (e.g. diethylene glycol dimethyl ester, diethylene glycol diethyl ester, diethylene glycol diacrylate, diethylene glycol distearate, diethylene glycol dimethacrylate, tetraethylene glycol dicrotone), polyethylene glycol oleate, polyethylene glycol di- n-butyrate, polyethylene glycol silacrate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polyethylene glycol dicrotonate, polyethylene glycol di-
α-cyanoacrylate, polyethylene glycol stearyl methacrylate, polyethylene glycol lacryl acrylate, etc.

), polyalkylene glycol monoether monoesters (e.g., acrylates, methacrylates, and tarotonates of glycol monoether compounds such as Eva, methyl carpitol, tetraoxyethylene methyl ether, polyoxyethylene lacryl ether, and polyoxyethylene nonylphenyl ether) ), other bisphenol A-polyalkylene oxide adducts, trimethylolpropane-polyalkylene oxide adducts, glycerin-polyalkylene oxide adducts, adipic acid-polyalkylene oxide adducts, trimethic acid-polyalkylene oxide adducts, etc. Examples include alkylene oxide adducts.

Other cyclic compounds include, for example, 18-crown-
6, 15-crown-5, 18-crown-5, dithia-15-crown, dibenzo-18-curacune-6, dicyclohexyl-18-crown-6, 1,2-naphtho-15-crown-5, 1,2-methylbenzo-18-
Crown-6 and the like can also be used.

In the present invention, the formula (
Examples of the polyhydroxy compound III) include catechol, pyrogallol, and 1,2,4-benzenetriol.

In the present invention, the formula (
The carboxylic acid and its anhydride and ester compounds in III) must not have one or more free carboxy groups, unless the compound has two or more phenolic hydroxyl groups. No. Specific examples of these carboxylic acids are listed below, but the invention is not limited thereto.

Examples of aliphatic carboxylic acids include formic acid, acetic acid, glycolic acid, β-hydroxypropionic acid, lactic acid, α-hydroxyisobutyric acid, mannonic acid, gluconic acid, malonic acid, oxalic acid, malonic acid, succinic acid, succinic anhydride, α -Ketosuccinic acid, α-methylsuccinic acid, methylmalonic acid, glutaric acid, glutaric anhydride, maleic acid, itaconic acid, itaconic acid monoethyl ester, tartronic acid, ethylculturonic anhydride, malic acid, α-oxy-α- Methylsuccinic acid, methyltartaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, ■-methyl-butane-1,4-dicarboxylic acid, 2-methylene-5=methyladipic acid, muconic acid, butenylsuccinic anhydride, α-thaloladipine acid, ethylene bispropionic acid, aconitic acid, aconitic acid di-n-butyl ester, 1-butene-2.3.4
-tricarboxylic acid, carboxymethyloxysuccinic acid 1-
Cyano-propane-1.2.3-tricarboxylic acid, ethane-1.1,2.2-tetracarboxylic acid, cyclohexanedicarboxylic acid and its anhydride, 3-methy/l/hexene-4.5.6 -T! J carboxylic acid, cyclopenkunetetracarboxylic acid, 1,2-cyphyromo-3-notylcyclohexane-4.5.6-)licarboxylic acid, cinnamic acid, m-hydroxycinnamic acid, mandelic acid, attractic acid, l- Examples include 7enyloxybutane-2,4-dicarboxylic acid.

Examples of aromatic carboxylic acids include benzoic acid, salicylic acid, 3-hydroxy-2-nitrobenzoic acid, vanillic acid, 5-hydroxy-3methylbenzoic acid, 5-nitrovanilic acid, resorcylic acid, furotocatechuic acid, and protocatechuic acid. Acid propyl ester, piperonic acid, gallic acid, dichlorogallic acid, gallic acid methoxyethyl ester, 3
, 6-dichlorophthalic acid, 4,5-dioxyphthalic acid,
3-nitrophthalic anhydride, diphenic acid, naphthalene 1,
Examples include 5-dicarboxylic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid, and pyromellitic anhydride.

Examples of the peterocyclic carboxylic acid include quinolinic acid, pyrrole-2,3-dicarboxylic acid, and chimexaline-2,3-dicarboxylic acid.
-dicarboxylic acid, 2,5-thiophenedicarboxylic acid, tetrahydrofurantetracarboxylic acid, and the like.

The polyhydric alcohols used in the present invention have the formula [
The ether compound having the repeating unit represented by formula [■] can also be used in combination with two or more selected from these groups, and the amount of these compounds to be used is determined by It is preferable that the amount of hydroxybenzene is determined comprehensively by the amount of carboxylic acid represented by the formula [■]. However, the amount of polyhydric alcohol and/or ether compound added is usually 0.05 to 20% by weight based on α-cyanoacrylate, and the amount of polyhydroxybenzene or/and carboxylic acid added is α-cyanoacrylate.
-For cyanoacrylate, o, o o o i~
A range of 0.5% by weight is particularly good; too little of both will not change the effect, but adding too much of either will cause α
-It is undesirable because it lowers both the curing speed and adhesive strength of the cyanoacrylate monomer.

The adhesive composition of the present invention has excellent initial adhesive strength when adhering to adherends that are slightly acidic compared to other materials such as wood, chrome plating, nickel plating, polyester (FRP), Bakelite, etc. is recognized. Although it is not clear why (1) polyhydric alcohols, specific ether compounds, and (2) specific polyhydroxybecyanoacrylates have such effects, (]) and (
It is thought that the curing rate of α-cyanoacrylate is accelerated by some interaction of the compound group 2).

Additionally, the adhesive obtained in the present invention contains stabilizers that have been conventionally added to α-cyanoacrylate adhesives (for example, anionic polymerization inhibitors such as sulfur dioxide, sulfonic acid, and sultone, hydroquinone, radical polymerization inhibitors such as hydroquinone monomethyl ether),
Thickeners (for example, polymethyl methacrylate), plasticizers, colorants, fragrances, solvents, etc. can also be added and blended as appropriate depending on the purpose within a range that does not impede the stability of the monomer.

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples. All percentages in the examples indicate weight percentages, and the adhesive strength was measured by the following method.

Glue two steel plates (100x25x1.6 moromi) with an area of 25
X 12.5 layers and adhesive, 20℃, 60%RH
After 5 minutes and 24 hours, the tensile shear strength was measured at a tensile rate of 50 mm/h,
It is expressed in f/tri.

Examples 1 to 9, Comparative Examples 1 to 3 Ethyl α-cyanoacrylate monomer containing 0.002% of sulfur dioxide as an anionic polymerization inhibitor and 0.1% of hydroquinone as a radical polymerization inhibitor. The various polyhydric alcohol derivatives shown in Table 1 were added to the acrylate adhesive in an amount of 2% based on α-cyanoacrylate, and the formula [■] or [I
IT] and 0.05% of various carboxylic acids shown in Table 1.
It was shown to.

In addition, the ethyl α-cyanoacrylate adhesive used in this example (no addition of polyhydric alcohol or carboxylic acid) and the adhesive containing only either polyhydric alcohol or carboxylic acid can also be used. test,
The results are shown in Table 1 as a comparative example.

As shown in Table 1, the initial adhesive strength of the α-cyanoacrylate adhesive prepared by mixing polyhydric alcohol or its derivative with pyrogallol or various carboxylic acids is significantly improved.

Examples 10-18, Comparative Examples 4-8 0.001 sulfur dioxide for ethyl α-cyanoacrylate monomer
Polyethylene glycol distearate, polyethylene glycol monomethyl monomethacrylate, pyrogallol, gallic acid methoxyethyl ester, and itaconic acid were added to an ethyl α-cyanoacrylate adhesive containing 5% and 0.1% of hydroquinone in various amounts shown in Table 2. The adhesive strength of each was measured and the results are shown in Table 2.

However, polyethylene glycol distearate was used after being dissolved in the same amount of dioxane as shown in the table. There was no effect on storage stability.

From Table 2, the ether compounds of formula [■], formula CIII, and formula [
1] A wide range of mixing ratios with N compounds is recognized,
The improvement in initial bond strength is obvious.

Examples 19-22 Polyethylene glycol distearate to alpha-cyanoacrylate in an ethyl alpha-cya/acrylate adhesive containing 0.002% sulfur dioxide and 0.1% hydroquinone to ethyl alpha-cyanoacrylate monomer. Further, 0.05% of various carboxylic acids shown in Table 3 were blended, and a steel-to-steel adhesion test was conducted, and the results are shown in Table 3.

=26 In this example, the relationship between hydroxycarboxylic acid and its ester was investigated in the carboxylic acid of formula [l11].

Examples 19, 20 and 21 are examples of aromatic carboxylic acids in which A is free and B is ester. In these three examples, Examples 19 and 20 are trivalent and divalent hydroxy compounds, respectively, so there is no difference in effectiveness between the free acid and the ester, and both improve the initial adhesive strength and the strength after 24 hours. ing. However, in the monohydric hydroxycarboxylic acid of Example 21, its ester (21B) has a poor improvement effect.

For aliphatic carboxylic acids, even divalent hydroxy compounds, as seen in Example 22D for aromatic carboxylic acids,
Ester has a poor effect on improving both the initial adhesive strength and the strength after 24 hours.

Examples 23-35 Ethyl α-cyanoacrylate adhesives containing 0.002% sulfur dioxide and 0.1% hydroquinone based on ethyl α-cyanoacrylate monomer were subjected to repetition of formula CI′) shown in Table 4. Table 4 shows the results of a steel-to-steel adhesion test obtained by blending various ether compounds containing 27- and various compounds of formula [■] and formula [■]. In each example, the initial adhesive strength and the strength after 24 hours were improved.

Examples 36 to 57 Repeating the formula [■] shown in Table 5 to an ethyl α-cyanoacrylate adhesive containing 0.0015% sulfur dioxide and 0.1% hydroquinone to ethyl α-cyanoacrylate monomer. Various ether compounds containing an ester unit and various compounds of formula [11') or formula [■] were combined and subjected to a steel-to-steel adhesion test, and the results are shown in Table 5.

In each example, the initial adhesion strength and the strength after 24 hours were improved.

Examples 58-60 Comparative Examples 9-11 0.00 iota dioxide relative to ethyl α-cyanoacrylate monomer
Ethyl alpha containing 18% and hydroquinone 0.05%
- In the cyanoacrylate adhesive, polyethylene glycol distearate is added to α-cyanoacrylate at 0%
．． Further, 0.05% of the compound of formula [111) shown in Table 6 was blended with respect to α-cyanoacrylate,
Similar adhesives such as steel, lauan plywood, chrome-plated steel, and Bakelite were bonded to each other using the respective adhesives, and an adhesion test was conducted. The results are shown in Table 6.

The adhesion test method is as follows:
steel, chrome plated steel), 2wn (Bakelite), 3W
n (lauan plywood)) with an adhesion area of 25 x 12.5 m, and cured under environmental conditions of 20°C and 60% RH. For steel and Bakelite, after 5 minutes and 24 hours, lauan plywood and chrome plating were bonded. The tensile shear strength of the steel was measured after 3 minutes and 24 hours, and the results are shown in Table 6. The unit is K
gf/crA.

According to the results revealed in Table 6, even with conventional α-cyanoacrylate adhesives, the initial adhesion was poor, and porous materials such as wood, which were virtually impossible or difficult to bond to, as well as chromium It is clear that adherends such as plated steel, Bakelite, etc. will also serve the purpose of adhesion satisfactorily using the alpha-cyanoacrylate adhesive of the present invention.

In Table 6, the tensile shear strength in the upper row is the measured value after 5 minutes of adhesion for steel and Bakelite, the measured value after 3 minutes for lauan plywood and chrome-plated steel, and the lower row is the strength after 24 hours. Also, *marks indicate broken wood.

32- 33-

Claims (1)

[Claims] 1. Q! - cyanoacrylate (1) polyhydric alcohol or derivative thereof, or formula CI) (wherein X1 and
2 represents a hydrogen atom, a halogen atom, a hydroxyl group, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or an aralkyl group, and X and X2 may be the same or different. p represents an integer of 1 or more, q represents an integer of 2 or more, and the terminal may be formed into a ring. ) a compound selected from the group of compounds having a repeating unit of formula [1
1] (In the formula, r is 2 to 3, and at least two hydroxyl groups are in adjacent positions.) or a polyhydroxy compound represented by the formula [■] (HOOC”)pA→C0OR+)I CIII
)] (wherein A is a hydrogen atom or a substituted residue or an unsubstituted hydrocarbon residue or a heterocyclic compound residue, R3 is a substituted or unsubstituted hydrocarbon residue, an integer such that e≧1, Indicates an integer of f≧0.However, if A has two or more phenolic hydroxyl groups, e-0 may be used only when f≧1.Also, polycarboxylic acids can be ring-closed to form anhydrides. An α-cyanoacrylate adhesive composition comprising a compound selected from the group of carboxylic acids and esters shown in the following formula. However, α-cyanoacrylate has the formula (3) [rV)[I
V) [In the formula, X3 is a hydrogen atom or a methyl group; ). However, when X4 is a cyano group, it is excluded that X5 is a hydrogen atom. 1, m, and n are integers, and (l+m)≧1 and n≧1. ]
A polyether compound represented by (4) pyrogallol or formula [V] (OH)h (wherein R3 is a hydrogen atom or a substituted or unsubstituted hydrocarbon residue, and h is an integer of 2 or more ) except when blending with polyhydroxycarboxylic acids shown in .).