Mechanical properties of epoxy systems modified by polyacrylates

Ethyl acrylate(EA) and butyl acrylate(BA) were employed to modify the diglycidyl ether of bisphenol A (DGEBA)-methyltetrahydrophthalic anhydride (MeTHPA) epoxy system via in-situ polymerization. The "sea-island" structure is observed from the SEM micrographs of the DGEBA-MeTHPA system modified by polyacrylates. By the addition of 10% (mass fraction) EA and BA, the tensile strength of the epoxy system reduces by 9.51% and 4.00%, and the modulus reduces by 14.81% and 9.52%, respectively. The glass transition temperature is not obviously influenced by the addition of polyacrylates. By contrast, the impact strength dramatically increases by 26.5% and 31.0%, and the elongation increases by 22.03% and 30.07%, respectively, showing obvious toughening effects.