Effect of tunable styrene content on achieving high-performance poly(styrene-b-ethylene-ran-butylene-b-styrene)/graphene oxide nanocomposites

In this paper, two poly(styrene-b-ethylene-ran-butylene-b-styrene) (SEBS) with different styrene segment content were adopted to explore the relationship between varying π-π stacking interaction and the mechanical performance of polymer composites. The results showed that the high styrene content on SEBS (SEBS-30, 30 wt% styrene segment) endows SEBS a stronger π-π stacking interaction with GO and a better dispersion of GO in the matrix than that in SEBS with low styrene content (SEBS-12, 12 wt% styrene segment), resulting in a high efficiency on enhancing the performance of SEBS. By adding 0.5 wt% GO, the tensile strength and modulus of SEBS-30 was increased by 44% and 64%, respectively, while that of SEBS-12 was increased by 24% and 39%. Furthermore, the GO also exhibited the ability to toughen SEBS via forming microcrack and GO-induced fibrillation of SEBS during the fracture process. The elongation at break and fracture toughness of SEBS-30 was increased by 10% and 64%, respectively. This study gives us a deep insight into the influence of varying π-π stacking interaction between graphene oxide (GO) and polymer on achieving high-performance polymer nanocomposites.