Polymeric nanocomposites have been fabricated via in situ cationic polymerization of linseed oil in the presence of surface-modified graphene oxide (SGO). The interfacial interactions between SGO nanoplatelets and the polymer matrix were investigated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), which revealed a uniform distribution of SGO throughout the polymer matrix at a lower concentration (<2 wt%), but that higher loading of SGO (2 wt%) results in agglomeration. Nanomechanical characterization revealed the enhancement of the mechanical properties of nanocomposites at low concentrations of nanofillers (<2 wt%). Under dynamic mechanical analysis, the nanocomposites exhibited superior dynamic modulus with respect to the polymer matrix, demonstrating the great reinforcement potential of SGO nanofillers. Also, the thermal stabilities of the nanocomposites effectively improved with an increase in the filler loading. In shape memory tests, the nanocomposites fully recovered their original shape under different stimuli, and the fast shape recovery was observed with an increase in the content of SGO nano fillers.