Adhesive composition

Patent metadata

Field	Value
Publication number	US-9458361-B2
Application number	US-201314650946-A
Country	US
Kind code	B2
Filing date	Dec 3, 2013
Priority date	Dec 14, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

An curable adhesive composition that can form a cured product exhibiting high shear adhesion strength, peel adhesion strength and impact adhesion strength and exhibiting, in particular, excellent cold/hot cycle resistance of adhesion strength, includes (a) a 2-cyanoacrylic acid ester, (b) a high molecular-weight component, such as a polymer, compatible with the 2-cyanoacrylic acid ester, (c) a multifunctional 2-cyano-3-vinylacrylic acid ester, and (d) an onium salt represented by the following general formula (1):

C + A −   (1)

wherein C + represents an onium cation, A − represents an anion such provided that the anion does not substantially initiate polymerization of the 2-cyanoacrylic acid, in which the curable adhesive contains components (b)-(d) in predetermined amounts relative to 100 parts by mass of the component (a).

First claim

The invention claimed is:

1. An adhesive composition which comprises
(a) a 2-cyanoacrylic acid ester,
(b) a high molecular weight component compatible with the 2-cyanoacrylic acid ester,
(c) a multifunctional 2-cyano-3-vinylacrylic acid ester having 2 or more 2-cyano-3-vinylacryloyl groups, and
(d) an onium salt represented by the following general formula (1):
C + A −   (1)

wherein C + represents an onium cation and A − represents an anion which does not substantially initiate polymerization of the 2-cyanoacrylic acid ester, and
in which the contents of the components (b), (c), and (d) are from 2 to 50 parts by mass, from 1 to 200 parts by mass, and from 0.01 to 5 parts by mass, respectively, relative to 100 parts by mass of the component (a).

2. The adhesive composition according to claim 1 , wherein the high molecular-weight component (b) is a copolymer resulting from a monomer capable of forming a polymer slightly soluble in the 2-cyanoacrylic acid ester and a monomer capable of forming a polymer soluble in the 2-cyanoacrylic acid ester.

3. The adhesive composition according to claim 2 , wherein the monomer capable of forming a polymer slightly soluble in the 2-cyanoacrylic acid ester is at least one selected from the group consisting of ethylene, propylene, isoprene, and butadiene, and the monomer capable of forming a polymer soluble in the 2-cyanoacrylic acid ester is at least one of acrylic acid esters and methacrylic acid esters.

4. The adhesive composition according to claim 1 , wherein the multifunctional 2-cyano-3-vinylacrylic acid ester (c) is selected from the group consisting of an ester of 2-cyano-3-vinylacrylic acid with a polyoxyalkylene polyol, a polyester polyol, a polycarbonate polyol, a polyurethane polyol, a polyamide polyol, a polyester polyimide polyol, an acrylic polyol, a polybutadiene polyol, a hydrogenated polybutadiene polyol, an ethylene-butylene copolymer polyol, a polyisoprene polyol, a hydrogenated polyisoprene polyol, a polyvinyl butyral, a polyvinyl formal, a polyvinyl alcohol, a phenolic resin, and a silane or siloxane compound having hydroxyl groups on both terminals thereof.

5. The adhesive composition according to claim 1 , wherein the number average molecular weight of the multifunctional 2-cyano-3-vinyl-acrylic acid ester (c) is from 1000 to 50000.

6. The adhesive composition according to claim 1 , wherein the anion A − of the onium salt represented by the general formula (1) is hydrogen sulfate anion, hydrogen sulfite anion, a sulfonate anion represented by R 1 SO 3 − wherein R 1 represents an alkyl group, perfluoroalkyl group having 1 to 10 carbon atoms, vinyl group, aryl group, perfluoroaryl group, or halogen atom; or a bis(substituted sulfonyl)imide anion represented by (R 2 SO 2 ) 2 N − wherein R 2 represents an alkyl group, perfluoroalkyl group having 1 to 10 carbon atoms, or aryl group.

7. The adhesive composition according to claim 1 , which, after being cured, forms a sea-island structure comprising a dispersed phase resulting from polymerization product of the 2-cyanoacrylic acid ester (a) and a continuous phase resulting from the high molecular-weight component (b), wherein the dispersed phase exhibits a rate of change of the maximum particle diameter of not more than twice after thermal treatment at 60° C.

8. The adhesive composition according to claim 1 , wherein the high molecular-weight component (b) is a copolymer resulting from a monomer capable of forming a polymer slightly soluble in the 2-cyanoacrylic acid ester and a monomer capable of forming a polymer soluble in the 2-cyanoacrylic acid ester, and the number average molecular weight of the multifunctional 2-cyano-3-vinyl-acrylic acid ester (c) is from 1000 to 50000.

9. The adhesive composition according to claim 8 , wherein the monomer capable of forming a polymer slightly soluble in the 2-cyanoacrylic ester comprises ethylene, propylene, isoprene, butadiene, chloroprene, 1-hexene, cyclopentene, or any combination thereof, and wherein the monomer capable of forming a polymer soluble in the 2-cyanoacrylic acid ester comprises acrylic acid ester(s), methacrylic acid ester(s), vinyl chloride, vinyl acetate, vinyl ether, styrene, acrylonitrile, or any combination thereof.

10. The adhesive composition according to claim 1 , wherein the high molecular weight component compatible with the 2-cyanoacrylic acid ester comprises a copolymer and has a weight average molecular weight (Mw) and number average molecular weight (Mn) so that a ratio of Mw/Mn is a range of 1.0 to 10.0.

11. The adhesive composition according to claim 1 , wherein the (b) a high molecular weight component compatible with the 2-cyanoacrylic acid ester comprises a polymer.

12. The adhesive composition according to claim 1 , wherein the (b) a high molecular weight component compatible with the 2-cyanoacrylic acid ester comprises an acrylic acid ester-based copolymer elastomer, a styrene-butadiene copolymer-based elastomer, a polyurethane-based elastomer, a carboxylated acrylonitrile-butadiene copolymer-based elastomer; a polyester-based elastomer, an epichlorohydrin-based elastomer, an ethylene-vinyl acetate copolymer-based elastomer, or a combination of any thereof.

13. The adhesive composition according to claim 3 , wherein the multifunctional 2-cyano-3-vinylacryiic acid ester (c) comprises an ester of 2-cyano-3-vinylacrylic acid with a polyoxyalkylene polyol, a polyester polyol, a polycarbonate polyol, a polyurethane polyol, a polyamide polyol, a polyester polyamide polyol, an acrylic polyol, a polybutadiene polyol, a hydrogenated polybutadiene polyol, an ethylene-butylene copolymer polyol, a polyisoprene polyol, a hydrogenated polyisoprene polyol, a polyvinyl butyral, a polyvinyl formal, a polyvinyl alcohol, a phenolic resin; or a silane or siloxane compound having hydroxyl groups on both terminals thereof.

14. A curable adhesive composition comprising
(a) a 2-cyanoacrylic acid ester,
(b) a polymer compatible with the 2-cyanoacrylic acid ester, said polymer having a number average molecular weight in a range of 5,000 to 500,000,
(c) a multifunctional 2-cyano-3-vinylacrylic acid ester having 2 or more 2-cyano-3-vinylacryloyl groups, wherein the number average molecular weight of the multifunctional 2-cyano-3-vinyl-acrylic acid ester (c) is from 1000 to 50000, and
(d) an onium salt represented by the following general formula (1):
C + A −   (1)

wherein, C + represents an onium cation and A − represents an anion comprising a hydrogen sulfate anion, a hydrogen sulfite anion, a sulfonate anion represented by R 1 SO 3 − wherein R 1 represents an alkyl group, a perfluoroalkyl group having 1 to 10 carbon atoms, a vinyl group, an aryl group; a perfluoroaryl group, a halogen atom, or a bis(substituted sulfonyl)imide anion represented by (R 2 SO 2 ) 2 N − wherein R 2 represents an alkyl group, a perfluoroalkyl group having 1 to 10 carbon atoms, or an aryl group, and
wherein the contents of the components (b), (c), and (d) are from 2 to 50 parts by mass, from 1 to 200 parts by mass, and from 0.01 to 5 parts by mass, respectively, relative to 100 parts by mass of the component (a).

15. The adhesive composition according to claim 14 , wherein the (b) the polymer comprises a copolymer and has a weight average molecular weight (Mw) and number average molecular weight (Mn) so that a ratio of Mw/Mn is a range of 1.0 to 10.0.

16. The adhesive composition according to claim 14 , wherein the (b) polymer comprises a copolymer of a first monomer comprising ethylene, propylene, isoprene, butadiene, chloroprene,

Assignees

• Toagosei Co Ltd

Inventors

• Ishizaki Kenichi
• Ando Yushi

Classifications

• C08F222/328

  Alpha-cyano-acrylic acid with more than one oxygen in the ester moiety · CPC title

• C09D135/04

  Homopolymers or copolymers of nitriles (C09D135/06, C09D135/08 take precedence) · CPC title

• C09J11/06

  organic · CPC title

• C09J201/00

  Adhesives based on unspecified macromolecular compounds · CPC title

• C08F2222/328

  Chemistry & Metallurgy · mapped topic