One-component epoxy-modified polyurethane and/or polyurea adhesives having high elongation and excellent thermal stability, and assembly processes using same

A one-component epoxy-modified polyurethane and/or urea adhesive comprising in admixture:

• components A and B, wherein component A) is one or more non-rubber-modified epoxy resins and component B) is one or more rubber-modified epoxy resins;
• C) one or more reactive urethane group- and/or urea group-containing tougheners having a number average molecular weight of up to 35,000, at least one polyether or diene rubber segment having a weight of at least 1000 atomic mass units, and capped isocyanate groups of which at least 75% are monophenol- or polyphenol-capped isocyanate groups;
• D) optionally, one or more core-shell rubbers;
• E) one or more latent epoxy curing agents;
• and
• F) at least one catalyst for the reaction of an epoxide with the curing agent(s);
• wherein
• 1) component A constitutes 10 to 25 percent of the combined weight of components A-E;
• 2) component B constitutes 2 to 30 percent of the combined weight of components A-E;
• 3) components A and B together constitute 12 to 40 percent of the combined weight of components A-E;
• 4) component C constitutes 55 to 85 percent of the combined weight of components A-E;
• 5) components B, C and D together constitute 65 to 85 percent of the combined weight of components A-E;
• 6) component D constitutes 0 to 15 percent of the combined weight of components A-E;
• and
• 7) components A-E together constitute at least 60 weight percent of the one-component epoxy adhesive.