Transmission electron microscopy observations on fine structures of shish-kebab crystals of isotactic polystyrene by partial melting

The composite morphology and melting behavior of isothermally cold-crystallized isotactic polystyrene (iPS) shish-kebab crystals have been studied by transmission electron microscopy (TEM). The fine structures of iPS shish-kebabs are reflected at lamellar resolution by partial melting treatment using bright- and dark-field imaging modes. TEM observations indicate that the entire shish-kebab entity consists of several components: the central extended-chain micro-shish crystals, the partially extended-chain macro-shish crystals which are intrinsically connected with the microshish cores, the overgrown micro-kebabs by primary crystallization, and the macro-kebabs formed by secondary crystallization on macro-kebab nuclei. The reversible morphological transformation between the micro- and macro-kebabs has been visualized on nanoscale via melting and recrystallization processes, due to the difference in their thermal stability. (C) 2002 Elsevier Science B.V. All rights reserved.