Cyanoacrylate compositions

1. A cyanoacrylate composition comprising:

(a) a cyanoacrylate component;

(b) a toughening agent comprising a copolymer of ethylene and vinyl acetate, wherein the vinyl acetate content in the copolymer is in an amount of about 50 wt % to about 95 wt %, based on the total weight of the copolymer, and wherein the toughening agent is present in the composition in an amount of about 2 wt % to about 25 wt %, based on the total weight of the cyanoacrylate composition;

(c) a component having at least two (meth)acrylate functional groups having the formula:

wherein R 1 and R 2 are the same or different and are selected from the group consisting of H or Me; and wherein X is a C 4 to C 30 alkyl chain and wherein said chain is optionally substituted with one or more acrylate and/or methacrylate functional groups, and/or one or more C 1 -C 10 alkyl groups;

(d) a benzonitrile component; and

(e) an anhydride component.

2. The cyanoacrylate composition according to claim 1 , wherein the toughening agent comprises an ethylene-vinyl acetate copolymer comprising 70 wt % vinyl acetate to 95 wt % vinyl acetate based on the total weight of the copolymer.

3. The cyanoacrylate composition according to claim 1 , wherein the toughening agent is present in an amount of from about 4 wt % to about 25 wt % based on the total weight of the cyanoacrylate composition.

4. The cyanoacrylate composition according to claim 1 , wherein the component having at least two (meth)acrylate functional groups is present in an amount of from about 1.5 wt % to about 20 wt % based on the total weight of the cyanoacrylate composition.

5. The cyanoacrylate composition according to claim 1 , wherein the benzonitrile component is present in an amount of from about 0.01 wt % to about 10 wt % based on the total weight of the cyanoacrylate composition.

6. The cyanoacrylate composition according to claim 1 , wherein the anhydride component is present in an amount of from about 0.05 wt % to about 5 wt % based on the total weight of the cyanoacrylate composition.

7. The cyanoacrylate composition according to claim 1 , wherein the cyanoacrylate component comprises ethyl-2-cyanoacrylate or allyl-2-cyanoacrylate.

8. The cyanoacrylate composition according to claim 1 , wherein the cyanoacrylate component comprises a combination of ethyl-2-cyanoacrylate and allyl-2-cyanoacrylate.

9. The cyanoacrylate composition according to claim 1 , wherein the component having at least two (meth)acrylate functional groups is selected from:

10. The cyanoacrylate composition according to claim 9 wherein the component having at least two (meth)acrylate functional groups is hexanediol diacrylate.

11. The cyanoacrylate composition according to claim 1 , wherein the benzonitrile component is a member selected from the group consisting of 3,5-dinitrobenzonitrile, 2-chloro-3,5-dinitrobenzonitrile, pentafluorobenzonitrile, 2-fluoro-4-(trifluoromethyl)benzonitrile, tetrachloroterephthalonitrile, tetrafluorophthalonitrile and tetrafluoroisophthalonitrile.

12. The cyanoacrylate composition according to claim 1 , wherein the anhydride component is an aromatic anhydride.

13. The cyanoacrylate composition according to claim 1 , wherein the anhydride is a hydrogenated anhydride.

14. The cured cyanoacrylate composition according to claim 1 .

15. A method of bonding together two substrates, comprising the steps of applying a cyanoacrylate composition according to claim 1 , to at least one of the substrates, and mating together the substances for a time sufficient to permit an adhesive bond to form from the cyanoacrylate composition between the mated substrates.

16. A bonded assembly comprising:

a first substrate having a first surface;

a second substrate having a second surface; and

a cured cyanoacrylate composition disposed between said first and second surfaces, said composition, prior to cure, comprising a cyanoacrylate composition according to claim 15 .