The miscibility in the melt and solid state of blends made of poly(p-phenylene sulphide) (PPS) with a liquid crystalline polymer (LCP) from DuPont was studied by polarized light optical microscopy (PLOM) and dynamic thermal mechanical analysis. Both techniques showed that the PPS and the LCP are immiscible in both states, and that the critical concentration for the formation of fibrils C*, in this particular system, was located between 20 and 25 wt % LCP. The resultant blend morphology was studied by PLOM and scanning electron microscopy (SEM). It was observed that when LCP fibrils are formed in the PPS matrix, the PPS macromolecules will crystallize around the LCP fibrils by forming columnar layers called transcrystallites. These transcrystallites are the result of the LCP acting as a nucleating agent for the PPS, promoting heterogeneous nucleation.