화학공학소재연구정보센터
Polymer, Vol.82, 87-92, 2016
Digital image correlation analysis of strain recovery in glassy polymer network isomers
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 3,3'- and 4,4'-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. (C) 2015 Elsevier Ltd. All rights reserved.