Provided herein are polyamine precursors useful in the manufacture of epoxy resins. Use of a polyamine precursor according to the invention provides an epoxy resin formulation having an increased working time over prior art amines used for curing epoxies. Increased working times translate to the ability to manufacture composites which could not be made using conventional epoxy curing agents, such as composite blades for wind-driven turbines. Such polyamines are also useful in polyurea formulations for lengthening reaction time, thus allowing more flow of applied polyurea coatings prior to gellation.