A hyperbranched polymer (HBP) additive is used to explore short-range molecular motions in the glassy state of crosslinked epoxy amine networks via subambient β relaxations as measured by dynamic mechanical thermal analysis. Increasing HBP addition increased modulus and stress, while reducing yield strain. Pre-reaction using an isocyanate linkage between the HBP and network comparatively reduced modulus while increasing stress and strain. Glassy state mobility of the epoxy amine network as a result of HBP addition, could be directly related to many changes in mechanical properties observed.
- Larry Q. Reyes
- Samuel R. Swan
- Russell J. Varley
