Structural adhesive compositions

Patent metadata

Field	Value
Publication number	US-10947428-B2
Application number	US-201514961513-A
Country	US
Kind code	B2
Filing date	Dec 7, 2015
Priority date	Nov 19, 2010
Publication date	Mar 16, 2021
Grant date	Mar 16, 2021

Abstract

Disclosed herein are compositions including (a) a first component comprising (1) an epoxy-adduct that is the reaction product of reactants comprising a first epoxy compound, a polyol, and an anhydride and/or a diacid and (2) a second epoxy compound; (b) rubber particles having a core/shell structure and/or graphenic carbon particles; and (c) a second component that chemically reacts with the first component at ambient or slightly thermal conditions. Also disclosed herein are compositions including (a) an epoxy-capped flexibilizer; (b) a heat-activated latent curing agent; and optionally (c) rubber particles having a core/shell structure and/or graphenic carbon particles; (d) an epoxy/CTBN adduct; and/or (e) an epoxy/dimer acid adduct. The heat-activated latent curing agent may include at least one reaction product of reactants including an epoxy compound and an amine and/or an alkaloid.

First claim

We claim:

1. A one-component composition comprising:
(a) 2% by weight to 40% by weight, based on total weight of the one-component composition, of an epoxy-capped flexibilizer comprising a reaction product of reactants comprising (i) an epoxy compound, (ii) an anhydride and/or a diacid, and (iii) a caprolactone;
(b) 3% by weight to 25% by weight, based on total weight of the one-component composition, of a heat-activated latent curing agent comprising dicyandiamide having a D98 maximum of 6 μm and a reaction product of reactants comprising an epoxy compound and an imidazole, wherein the epoxy compound comprises a polyepoxide and the molar ratio of the epoxy compound to the imidazole is 1:1 to 3:1;
(c) 5% by weight to 60% by weight, based on total weight of the one-component composition, of rubber particles having a core/shell structure and dispersed in an epoxy carrier resin; and
(d) 1% by weight to 15% by weight, based on total weight of the one-component composition, of an adduct of an epoxy compound and a dimer acid.

2. The composition of claim 1 , wherein the epoxy compound reactant (i) comprises Bisphenol A diglycidyl ether, phenyl diglycidyl ether, or combinations thereof.

3. The composition of claim 1 further comprising graphenic carbon particles, an epoxy/CTBN adduct or a combination thereof.

4. The composition of claim 1 , wherein the heat-activated latent curing agent (b) further comprises 3,4-dichlorophenyl-N,N-dimethyl urea.

5. The composition of claim 1 , wherein the composition is curable at a temperature below 140° C.

6. The composition of claim 1 , wherein the composition is heat-curable within 15 minutes or less.

7. The composition of claim 1 , wherein the composition is heat-curable within 15 minutes or less at a temperature of below 140° C.

8. The composition of claim 1 , which, when applied at 1 mm thick to hot dipped galvanized metal with a bond area of 20 mm×10 mm×0.25 mm, and following heating, has a measured lap shear strength of at least 15 MPa when tested at room temperature.

9. A method of adhering articles comprising:
(a) applying the composition of claim 1 to at least one of the articles; and
(b) heating the composition at a temperature of less than 140° C. for a time of less than 15 minutes to cure the composition and thereby adhering the articles together.

Assignees

• Ppg Ind Ohio Inc

Inventors

• Desai Umesh C
• Chao Tien-Chieh
• Nakajima Masayuki
• Ragunathan Kaliappa G

Classifications

• C08G59/4276

  Polyesters · CPC title

• C08G59/5006

  aliphatic · CPC title

• C08G59/184

  with amines · CPC title

• C08G59/066

  with chain extension or advancing agents · CPC title

• C08L2205/02

  containing two or more polymers of the same C08L -group · CPC title