Experimental Methods for the Viscoelastic Characterization of an Elastic Memory Composite Resin

An analytical model is being developed to predict the deployment rate of Elastic Memory Composites. The key components of this deployment rate model are the one dimension constitutive relationships of both the fiber and resin phases. The resin phase consists of a viscoelastic theromset epoxy resin with a reported glass transition temperature (T_g) of 71 degrees C. Since a typical deployment takes place within the temperature range from 23.9 degrees C to 79.4 degrees C, characterization at sample temperatures throughout this range was required. Due to the demanding nature of the planned creep experiments, significant effort was involved in the evaluation of the load frames and strain measurement devices to be used in these experiments. The strengths and weaknesses of each of these pieces of equipment will be presented. Following this evaluation, the final experimental setup included an MTS servo-hydraulic load frame / controller, and an MTS LX-300 Laser Extensometer. This load frame / controller combination provided the system responsiveness required by the creep method, while the laser extensometer provided a non-contact means of measuring strain across the wide range of temperatures sampled.