Storage‐stable epoxy B‐stage resins

N-Substituted β-aminopropionhydrazides, RNHC2h4CONHNH2, were prepared by the Michael addition of primary amines to acrylic esters. The adducts were converted to the corresponding hydrazides. The aminohydrazides react readily with terminal epoxides at moderate temperatures yeilding B-stage resins of excellent storage stability. When powdered B-stage resins are sprayed on hot metal (150-230°C.), a smooth cross-linked coating is formed in less than 3 min. The coatings have unusually high elasticity, they pass the Olson button test. For best performance the amine used should have the primary amino group attached to either a primary carbon atom or directly to an aromatic nucleus. Aminohydrazides with the following R. Groups have been prepared: methyl, n-butyl, sec-butyl, tert-butyl, phenyl, cyclohexyl, benzyl, octyl, dodecyl, and octadecyl.