Microstructure development and mechanical performance of MWCNTs/GNPs filled SEBS with different block content

Abstract

AbstractPolystyrene‐poly (ethylene‐butylene)‐polystyrene (SEBS) nanocomposites have been regarded as promising thermoplastic elastomers for several industries owing to their distinct molecular platforms and properties. However, extending their applications requires a thorough understanding of the microstructural changes that nanoparticles induce in SEBS chains. In this work, we used two types of SEBS varying in polystyrene (PS) hard block contents to study the relationship between the structural changes and viscoelastic/mechanical properties of SEBS hybrid nanocomposites containing different multi‐walled carbon nanotubes: graphene nanoplatelets ratios. According to the results, the viscoelastic responses were strongly influenced by the PS block content and nanoparticles ratio, which had an appreciable contribution to the nanoparticles' dispersion state. This was explained in terms of intensified microphase separation induced by the favorable interactions between the carbon‐based nanoparticles and PS blocks. It was also found that the samples containing higher hard block content demonstrated more significant mechanical performance and toughness, which were enhanced by the addition of nanoparticles such that the highest ultimate strength of 24.58 MPa was obtained for the S30C0.5G0.5 sample. Furthermore, some mechanisms, including molecular disentanglements, dissociation of inter/intra‐molecular interactions, the orientation of the rubbery polyethylene butylene chains, and PS microdomain rearrangement, were supposed to interpret the energy dissipation capability of SEBS nanocomposites.