Spreading of fast-curing, thermosetting silicones

Abstract

This letter presents an experimental study and the associated numerical modeling of fast-curing, thermosetting droplets spreading on a heated surface. The results show a significant morphological dependence of the spreading droplets of Ecoflex 0050 (a heat-sensitive, platinum-catalyzed silicone material) on thermal conditions. Differential scanning calorimetry and rheometry provide quantifiable data for modeling the cure kinetics and rheological properties of the material. This work demonstrates an approach to developing a phenomenological model suitable for predicting the morphological variation of fast-curing, thermosetting materials without prior knowledge of their chemical composition. The developed multiphysics models for cure kinetics and chemorheology can serve as a functional tool for predictions requiring accurate dimensional control of free-forming thermosetting materials, such as nozzle-based additive manufacturing, centrifugal coating and forming, fabrication of soft robots, and soft lithography.