Digital image correlation techniques were applied to compressive strain recovery experiments of glassy
network isomers to study architectural contributions to deformational response. Strain recovery experiments
provided a direct comparison of network isomer structure on viscoelastic deformation.
Diglycidyl ether of bisphenol-A (DGEBA) was cured with 3,30
- and 4,40
-diaminodiphenyl sulfone (33DDS
and 44DDS). The comparison revealed the networks have similar elastic and plastic strain components,
but differ in anelastic strain response. DGEBA cured with 44DDS developed pre-yield anelastic strain at a
significantly higher rate attributed to increase in free volume, molecular motions and energy dissipation.
In contrast, DGEBA cured with 33DDS displayed lower pre-yield energy dissipation attributed to lower
free volume and molecular motions, but exhibited a higher degree of post-yield strain-softening due to
larger segmental rearrangements