Abstract:

Through appropriate thermo-mechanical stimulation, shape memory polymers (SMPs) can exhibit autonomous shape-morphing capabilities, which are referred to as entropic elastic (EE) or reversible plastic (RP) intelligent responses. Currently, few studies in the literature address unified constitutive modeling for these two types of intelligent responses, and thermodynamic consistency is lacking. Here, we develop a unified thermodynamically consistent constitutive model that captures hyperelastic-viscoelastic and elasto-viscoplastic couplings, thereby reproducing both the EE and RP intelligent responses. Through verification against experimental data and results from subsequent mechanistic and parametric studies, the constitutive model can not only integrate the theoretical representations of these two phenomena into a mathematical framework, but also reveal the consistencies and differences between the two types of intelligent responses.

Key words: intelligent response, hyperelasticity-viscoelasticity, elasto-viscoplasticity, thermodynamic constitutive modeling