  Vitrimers are a special class of polymers that undergo dynamic cross-linking
under thermal stimuli. Their ability to exchange covalent bonds can be
harnessed to mitigate damage in a composite or to achieve recyclable aerospace
composites. This work addresses the primary challenge of modeling dynamic
cross-linking reactions in vitrimers during thermomechanical loading. Dynamic
bond exchange reaction probability change during heating and its effect on
dilatometric and mechanical response are simulated for the first time in large
scale molecular dynamics simulations. Healing of damage under thermal cycling
is computed with mechanical properties predicted before and after
self--healing.

Materials Science