The mechanical properties of polymers are strongly dependent on the rate of deformation. In particular, we are interested in how the elastic and fracture properties of polymers change as a function of mechanical testing rate. To study this problem, we are applying a microballistic-based measurement to understand the rate-dependent mechanical behavior of polymers from low impact speeds to ballistic speeds. We are particularly interested in the role of polymer architecture, such as network structure, backbone stiffness and side group flexibility, on the rate-dependent elasticity and fracture toughness of extremely tough polymers.