New evidence disclosed for the engineered strong interfacial interaction of graphene/rubber nanocomposites.

Interfacial interaction is of crucial importance for polymer nanocomposites. To improve interfacial interaction between graphene (GE) and isoprene rubber (IR), we grafted a silane coupling reagent, (bis-[γ-(triethoxysilyl) propyl]-etrasulfide), onto graphene oxide (GO). The modified GO was mixed with IR by solution blending and then reduced in situ to prepare IR/surface modified GE nanocomposites (IR/SGE). Raman mapping illustrates that the bound rubber on SGE is much thicker than that on unmodified GE, suggesting a strong interfacial interaction between SGE and IR. As a result, IR/SGE shows slower chain dynamics and lower strain-induced crystallinity than IR/GE. However, on-line Raman measurements show that the G band of IR/SGE shifts more noticeably during uniaxial tensile deformation than that of IR/GE; this suggests more efficient load transfer between SGE and IR. Consequently IR/SGE has better mechanical properties than IR/GE. [ABSTRACT FROM AUTHOR]