Structural recovery experiments have been performed in epoxy glasses subjected to rapid relative humidity changes. The premise of this study is that a change in moisture (plasticizer) content in the material is equivalent to a change in temperature because in both cases the distance from the glass transition is changed by either a constant relative humidity jump in temperature or an isothermal jump in relative humidity. As did Kovacs in his classic work on Poly (vinyl acetate), we have created a data set for volume recovery for the epoxy. However, even though the volume recovery data for the epoxy due to RH change are quite similar in nature to Kovacs' data in temperature change experiments a noticeable difference does exist in the kinetics in the two cases. In addition, the work also extends the TNM-KAHR model to the case of changing relative humidity.
展开▼
