Differential scanning calorimetry (DSC) was used to indicate the relative extents of the different cure reactions of the 4-glycityloxyl-N,
N-diglycidylaniline (MY0510), polyglycidyl ether of phenol formaldehyde novolac (DEN431) and 3,3 diamino diphenylsulphone
(3,3 DDS) resin systems and how these were affected by the presence of polyethersulphone (PES). The extent of reactions at
any given time decreased with increasing PES concentration and the reaction rate maximum shifted to longer times. The cured
resin systems were examined using dynamic mechanical analysis (DMA). Broader β-transitions of lower intensities were observed
in specimens containing PES, suggesting an increased range of relaxations within the transition.