. . "Likewise suitable are amines such as ethylenediamine, hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane (isophoronediamine, IPDA), 4,4???-diamino-dicyclohexylmethane, 1,4-diaminocyclohexane, 1,2-diaminopropane, hydrazine, hydrazine hydrate, amino acid hydrazides such as 2-aminoacetic hydrazide or bis-hydrazides such as succinic bishydrazide." . .