Patent ID: 8597734

Claim:
A peroxide-free curing system; the curing system comprising: 20-89.5% by weight of a compound having at least one epoxide group, 0.5-30% by weight of a polyamine, and 10-50% by weight of a citraconimide co-curing agent, wherein the co-curing agent has a formula corresponding to formula (I): and/or its tautomeric formulae (IIa) and/or (IIb): and/or formula (III): or a tautomer and/or an oligomer thereof; wherein D stands for branched (CR 1 R 2 ) n or where p is independently 0 or 1, and X is CH 2 , O, or SO 2 and stands for a meta- or para-benzene group; R is independently H or C 1-4 alkyl; R 1 and R 2 are independently H or (CH 2 ) m CH 3 ; wherein at least one group R 2 is (CH 2 ) m CH 3 and m being 0 to 2; n being 1 to 10; and n+m is 4 to 14; R′ coupled to a CH 2 group is equal to R; and P stands for phenyl, or unsubstituted or hydroxy-substituted C 1-6 alkyl or C 2-6 alkenyl; with the proviso that at least one of R is C 1-4 alkyl.