(721g) Controlled Topology Toughning Epoxy Via Incorporation of Partially Reacted Substructures

A method of toughening amine-cured epoxy systems was proposed and the resulting epoxy systems were characterized. Accordingly, a Monoamine-functionalized Partially Reacted Substructures (mPRS) resin was formed by partially curing a mixture of tetraglycidyl of diaminodiphenylmethane (TGDDM) and polyether monoamine (PEMA). Four different degree of polymerization of mPRS (0%,70%,75% and 80%) were added to a mixture of Diglycidyl Ether of Bisphenol A (DGEBA) at different concentration (0% to 25%) and the mixtures were cured. Based on the results of the quasi-static tensile test, the mechanical properties are tunable by control the conversion and concentration of mPRS, Young’s modulus (1.69 to 2.54 Gpa), yielding strength (39 to 59 Mpa) and failure strain (15% to 44%). Besides, the toughness improvement was also observed on fracture toughness and quasi-static compression test. The improved toughness was found to be due to an enhanced plastic microvoid growth as a result of the presence of the mPRS in the crosslinked structure of the mPRS-modified epoxy systems.