Cure accelerators for anaerobic curable compositions
Cure accelerators for anaerobic curable compositions, such as adhesives and sealants, are provided, and which are defined with reference to the compounds shown in structure I where A is CH 2 or benzyl, R is C 1-10 alkyl, R′ is H or C 1-10 alkyl, or R and R′ taken together may form a four to seven membered ring fused to the benzene ring, R″ is optional, but when R″ is present, R″ is halogen, alkyl, alkenyl, cycloalkyl, hydroxyalkyl, hydroxyalkenyl, alkoxy, amino, alkylene- or alkenylene-ether, alkylene (meth)acrylate, carbonyl, carboxyl, nitroso, sulfonate, hydroxyl or haloalkyl, and EWG is as shown, an electron withdrawing group, such as nitro, nitrile, carboxylate or trihaloalkyl.
1. An anaerobic curable composition comprising
(a) a (meth)acrylate component;
(b) an anaerobic cure-inducing composition; and
(c) a compound selected from one or more of
2. The composition according to claim 1 , wherein the anaerobic cure-inducing composition comprises a hydroperoxide selected from the group consisting of cumene hydroperoxide, para-menthane hydroperoxide, t-butyl hydroperoxide, t-butyl perbenzoate, benzoyl peroxide, dibenzoyl peroxide, 1,3-bis(t-butylperoxyisopropyl)benzene, diacetyl peroxide, butyl 4,4-bis(t-butylperoxy)valerate, p-chlorobenzoyl peroxide, t-butyl cumyl peroxide, t-butyl perbenzoate, di-t-butyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane, 2,5-dimethyl-2,5-di-t-butyl-peroxyhex-3-yne, 4-methyl-2,2-di-t-butylperoxypentane, t-amyl hydroperoxide, 1,2,3,4-tertramethylbutyl hydroperoxide and combinations thereof.
3. The composition according to claim 1 , further comprising at least one co-accelerator.
4. The composition according to claim 3 , wherein the co-accelerator is selected from the group consisting of amines, amine oxides, sulfimides, metals and sources thereof, acids, and mixtures thereof.
5. The composition according to claim 3 , wherein the co-accelerator is selected from the group consisting of triazines, ethanolamine, diethanolamine, triethanolamine, N,N-dimethyl aniline, cyclohexyl amine, triethyl amine, butyl amine, saccharin, N,N-diethyl-p-toluidine, N,N-dimethyl-o-toluidine, and acetyl phenylhydrazine with maleic acid, and mixtures thereof.
6. The composition according to claim 1 , further comprising at least one stabilizer.
7. The composition according to claim 6 , wherein the stabilizer is selected from the group consisting of benzoquinone, naphthoquinone, anthraquinone, hydroquinone, methoxyhydroquinone, butylated hydroxy toluene, ethylene diamine tetraacetic acid or a salt thereof, and mixtures thereof.
8. A method of using as a cure accelerator for anaerobic curable compositions a compound shown in structure I:
wherein A is CH 2 or benzyl, R is C 1-10 alkyl, R′ is H or C 1-10 alkyl, or R and R′ taken together may form a four to seven membered ring fused to the benzene ring, R″ is optional, but when R″ is present, R″ is halogen, alkyl, alkenyl, cycloalkyl, hydroxyalkyl, hydroxyalkenyl, alkoxy, amino, alkylene- or alkenylene-ether, alkylene (meth)acrylate, carbonyl, carboxyl, nitroso, sulfonate, hydroxyl or haloalkyl, and EWG is an electron withdrawing group, comprising the steps of:
(a) providing an anaerobic curable composition comprising a (meth)acrylate component and an anaerobic cure-inducing composition;
(b) providing as a cure accelerator for the anaerobic curable composition a compound shown in structure I:
wherein A is CH 2 or benzyl, R is C 1-10 alkyl, R′ is H or C 1-10 alkyl, or R and R′ taken together may form a four to seven membered ring fused to the benzene ring, R″ is optional, but when R″ is present, R″ is halogen, alkyl, alkenyl, cycloalkyl, hydroxyalkyl, hydroxyalkenyl, alkoxy, amino, alkylene- or alkenylene-ether, alkylene (meth)acrylate, carbonyl, carboxyl, nitroso, sulfonate, hydroxyl or haloalkyl, and EWG is an electron withdrawing group; and
(c) exposing the anaerobic curable composition and the cure accelerator to conditions favorable to cure the composition.
9. A method of making a compound shown in structure I:
wherein A is CH 2 or CH 2 phenyl (benzyl), R is C 1-10 alkyl, R′ is H or C 1-10 alkyl, or R and R′ taken together may form a four to seven membered ring fused to the benzene ring, R″ is optional, but when R″ is present, R″ is halogen, alkyl, alkenyl, cycloalkyl, hydroxyalkyl, hydroxyalkenyl, alkoxy, amino, alkylene- or alkenylene-ether, alkylene (meth)acrylate, carbonyl, carboxyl, nitroso, sulfonate, hydroxyl or haloalkyl, and EWG is an electron withdrawing group, for accelerating cure of anaerobic curable compositions comprising, reacting:
(a)
wherein R, R′, and R″ are as described above; and
(b) in the presence of a base, and an electron withdrawing group-containing methylene halide, an electron withdrawing group-containing tosylate or an electron withdrawing group-containing mesylate, wherein the electron withdrawing group is a member selected from the group consisting of esters, nitobenzyl and cyanobenzyl.
10. Compounds shown in structure I
wherein A is CH 2 or benzyl, R is C 1-10 alkyl, R′ is H or C 1-10 alkyl, or R and R′ taken together may form a four to seven membered ring fused to the benzene ring, R″ is optional, but when R″ is present, R″ is halogen, alkyl, alkenyl, cycloalkyl, hydroxyalkyl, hydroxyalkenyl, alkoxy, amino, alkylene- or alkenylene-ether, alkylene (meth)acrylate, carbonyl, carboxyl, nitroso, sulfonate, hydroxyl or haloalkyl, and EWG is an electron withdrawing group selected from the group consisting of esters, nitrobenzyl and cyanobenzyl.
11. Compounds selected from one or more of