  We use a particle-based mesoscale model that incorporates chemical reactions
at a coarse-grained level to study the response of materials that undergo
volume-reducing chemical reactions under shockwave-loading conditions. We find
that such chemical reactions can attenuate the shockwave and characterize how
the parameters of the chemical model affect this behavior. The simulations show
that the magnitude of the volume collapse and velocity at which the chemistry
propagates are critical to weaken the shock, whereas the energetics in the
reactions play only a minor role. Shock loading results in transient states
where the material is away from local equilibrium and, interestingly, chemical
reactions can nucleate under such non-equilibrium states. Thus, the timescales
for equilibration between the various degrees of freedom in the material affect
the shock-induced chemistry and its ability to attenuate the propagating shock.
