Characteristics of the DGEBA/MDA system modified with glutaronitrile

To improve the toughness of the cured DGEBA/MDA system, glutaronitrile (GN) was used as a chain extender. The cure kinetics was studied by two different DSC analyses and the mechanical and thermal properties were measured. With the addition of GN, the activation energy increased slightly but the cure rate decreased. This is because GN disturbs the reaction between epoxide and amine groups. Impact strength increased but glass transition temperature (T-g) and heat deformation temperature (HDT) decreased with increase in the GN content.