Thermal and morphological analysis of isotactic poly(1-butene) hydrogenated oligocyclopentadiene blends

This contribution discusses the influence of hydrogenated oligocyclopentadi ene (HOCP) on the morphology, the phase structure and the thermal propertie s of its blends with isotactic poly(1-butene) (PB-1) as a function of compo sition and crystallization conditions. PB-1 and HOCP are partially miscible in the melt state. The blends, in the solid state, form generally a three-phase system: a crystalline phase forme d by the polyolefin and two amorphous phases, of which one is rich in PB-1 and the other one in HOCP. The optical micrographs of the solidified blends show a morphology constituted by microspherulites and domains of HOCP-rich phase homogeneously distributed in intraspherulitic regions. Moreover, whe n the PB-1 and the blends are isothermally crystallized, hedrite-like cryst allites are observed. The crystallization process and the melting behavior are strongly influence d by the presence of the oligomer, since the addition of HOCP decreases the overall crystallization rate and the melting point of the blends. (C) 1998 Elsevier Science B.V.