EPITAXIAL CRYSTALLIZATION OF TRANS-1,4-POLYBUTADIENE ON HIGHLY ORIENTED ISOTACTIC POLY(PROPYLENE) FILMS

Epitaxial crystallization of trans-1,4-polybutadiene (PBD) on highly o riented isotactic poly(propylene) (iPP) has been investigated at diffe rent crystallization temperatures and rates. From electron microscopy and electron diffraction, it is confirmed that epitactic growth of the low-temperature modification (monoclinic) with microcrystals of PBD o n the iPP films takes place with their chain directions about +/- 50-d egrees apart. No epitaxial relationship occurs between the high-temper ature modification (hexagonal) of PBD and the iPP substrate. Thermal a nalyses of PBD-PP layered films indicate that the epitaxy has an impor tant effect on the formation of the high-temperature modification of P BD.