17 - Dynamic behavior of polymers

Abstract

Measuring, understanding, and modeling the high strain rate properties of polymers are of importance in a wide range of applications. These properties also give unique insight into the processes governing polymer deformation. Compared to metals, however, polymers present specific challenges, from measurement to data interpretation to modeling. This chapter aims to give a general introduction to, and overview of, the response of polymers to high strain rate deformation. Importantly, instead of treating this in isolation, it is described alongside a more general overview of polymer response and recommendations for further reading. We describe the key challenges in measuring and modeling mechanical properties of polymers at high strain rates and give an overview of experimental techniques, phenomenological observations, and modeling methods. In addition to an up-to-date description of the literature, the sections on experimental techniques and observations are supported by a historical overview, with a focus on exemplar polymers of different classes (amorphous, semicrystalline, rubbery, and foams) and other key topics: temperature rises and response under Taylor Impact. The modeling section gives an overview of modeling methods used, before describing the key concepts needed to understand physically motivated continuum constative models. These are then extended to encompass the additional concepts required for modeling the high strain rate response. Overall, this chapter gives a thorough overview of the broad range of concepts, techniques, and properties that must be appreciated by researchers before embarking on more detailed investigations of the response of polymers and polymer-based materials under high strain rate deformation.