Reduced graphene oxide enhances the crystallization and orientation of poly(ε-caprolactone)

Poly(ε-caprolactone) (PCL)/reduced graphene oxide (RGO) nanocomposite bars were prepared by injection molding, and the effects of RGO on the PCL matrix were investigated. Differential scanning calorimeter and polarized optical microscopy results demonstrated that RGO was an effective nucleation agent for PCL. Two-dimensional wide angle X-ray diffraction results showed that the incorporation of RGO can enhance the orientation degree of PCL crystals in the flow direction and did not influence the crystal structure of PCL. Two-dimensional small angle X-ray scattering results confirmed that the orientation of PCL chains in the flow direction was enhanced with the increase of RGO content, which was attributed to that RGO obstructed the motion of polymer chains. These results indicated that the incorporation of RGO can enhance the crystallization and orientation of PCL matrix, which was the major factor for the improvement of mechanical properties.