Patent ID: 7615595

Claim:
An epoxy adhesive composition comprising a) a first epoxy resin, b) a second epoxy resin modified with a copolymer based on a 1,3-diene and a polar, ethylenically unsaturated comonomer, c) a toughener selected from the group consisting of compounds of formula I wherein m is 1 or 2, n is 2 to 6, R 1 is an n-valent radical of an elastomeric prepolymer after the removal of the terminal isocyanate, amino or hydroxyl group, the elastomeric prepolymer being soluble or dispersible in epoxy resin, W and X are independently —O— or —NR 3 —, at least one of W and X being —NR 3 —, R 2 is an m+1-valent radical of a polyphenol or aminophenol after the removal of the phenolic hydroxyl group and optionally of the amino group, and R 3 is hydrogen, a C 1 to C 6 alkyl or phenol, and compounds of formula II wherein p is 1 or 2, q is 2 to 6, Y is —O—, —S— or —NR 6 —, Z is a radical selected from the group consisting of —OH, —NHR 6 , —OCN, R 4 is a residue of a hydroxyl-, mercapto- or amino-terminated polyether prepolymer or of a hydroxyl-, mercapto- or amino-terminated prepolymeric, segmented polyester, polythioester or polyamide R 5 is a carbocyclic aromatic or araliphatic p+1-valent radical with groups Z bonded directly to the aromatic ring, R 6 is hydrogen, C 1 to C 6 alkyl or phenyl, and R 7 is methyl or hydrogen, and mixtures thereof and d) a polymer comprising a polyester segment, said polymer being at least partially crystalline at room temperature and having a softening temperature in the range of 40° to 125° C.