  The ring opening polymerization of cyclic butylene terephthalate into poly
(butylene terephthalate) (pCBT) in the presence of reduced graphene oxide (RGO)
is an effective method for the preparation of polymer nanocomposites. The
inclusion of RGO nanoflakes dramatically affects the crystallization of pCBT,
shifting crystallization peak temperature to higher temperatures and, overall,
increasing the crystallization rate. This was due to a super nucleating effect
caused by RGO, which is maximized by highly reduced graphene oxide.
Furthermore, combined analyses by differential scanning calorimetry (DSC)
experiments and wide angle X-ray diffraction (WAXS) showed the formation of a
thick {\alpha}-crystalline form pCBT lamellae with a melting point of ~250
{\deg}C, close to the equilibrium melting temperature of pCBT. WAXS also
demonstrated the pair orientation of pCBT crystals with RGO nanoflakes,
indicating a strong interfacial interaction between the aromatic rings of pCBT
and RGO planes, especially with highly reduced graphene oxide. Such surface
self-organization of the polymer onto the RGO nanoflakes may be exploited for
the enhancement of interfacial properties in their polymer nanocomposites.
