A phthalonitrile resin reaction product of a curing agent of the following formula: ##STR4## wherein n is 1, 2, 3, 4 or 5; X is a hydrogen, a halogen, a halocarbon, an alkyl, an amino group or a amino group substituted with alkyls; Y is a hydrogen or an amino group; Y' is a hydrogen or an amino group and at least one Y or Y' must be an amino group, and a phthalonitrile monomer wherein the curing a