The effect of toughening agents on heat-resistance, mechanical and dielectric properties of epoxy resins used in radome materials

This paper discussed the effects of different toughening agents on heat resistance, mechanical properties, dielectric properties and moisture absorption properties of E-51/Dicy systems used in radome materials. Based on DSC results, we discussed the reactivity and heat resistance of the four systems. The bending properties and impact strength were tested to reveal the toughness of the resins. The dielectric properties and moisture absorption were also evaluated. The results revealed all the three toughening agents could increase the impact properties and decrease the dielectric constant, meanwhile moisture absorption was lower than the untreated sample. JER 1256 and PEK-C had more obvious effects on toughness and could also keep the heat resistance. The result of E-20 system showed the lowest ε and tgδ.