Deformation mechanism of thermoplastic vulcanizate (TPV) from a view of micromechanical scale

Abstract

Thermoplastic vulcanizates (TPVs) combine recyclability with strength but lack elasticity compared to elastomers. A Region Growing-Monte Carlo model accurately captured TPV's mesoscopic structure, showing just a 3.28 % deviation from experiments. Pure PP and PP network body models quantify PP matrix plastic deformation during stretching. TPV's rebound performance is influenced by the PP network and EPDM. During 30 % stretching, the equatorial PP matrix region exceeds 70 % strain and enters plastic flow, while other areas remain less strained. At particle intersections, the strain rate drops below 8 %. In recovery, the equatorial region opposes the process mechanically, a vital aspect of TPV's rebound mechanism. Non-equatorial PP matrix regions act as bonding points, with permanent deformation reflected in TPV's macroscopic behavior. This work provides key insights into enhancing TPV resilience from a micromechanical perspective.