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Abstract

Chemo-mechanical and chemo-thermal coupling in shape memory polymers: How computer simulations meet experiments It is well known that small additive molecules can enhance the relaxation dynamics in polymers and thereby decrease the glass transition temperature. This chemo-thermal coupling also has strong implications for mechanical response of polymers to an imposed deformation, thus leading to an interplay between chemo-thermal and chemo-mechanical coupling effects. Here, we focus upon this issue for the case of shape memory polymers and work out its consequences for shape recovery. The study combines experiments, molecular dynamics simulations and continuum scale modelling. It is shown that a simple model is capable of reproducing the experimentally observed effect of additive molecules on recovery temperature. Moreover, continuum scale samples can be adequately modelled by using experimental input. Finally, MD simulations predict interesting non-monotonic effects upon variation of additives’ molecular size.