| Abstract
| - Amorphous thin films of isotactic polystyrene (i-PS) were prepared by casting a hot solutionin p-xylene onto the hot water surface. Dried films mounted on the specimen grids for transmission electronmicroscopy (TEM) were crystallized from the glassy state by annealing. The crystalline thin films of i-PSthus prepared were examined by TEM. In these films, we could observe immature and more or less maturetwo-dimensional spherulites and sheaflike structures, the constituents of which are basically edge-onlamellae. As for the space-filling mechanisms of spherulitic growth, some models have been proposed sofar: for example, a model based on branching of straight lamellae and a model based on “spawning” ofnew lamellar crystals. In the latter model, however, most of the spawned lamellae are to be curved.From TEM observations, it is deduced that both branching and spawning occur together in the processof spherulitic growth of i-PS, because some lamellae are seemingly straight and branched but the majorityof lamellae are curved. In addition, the (300) lattice images obtained by high-resolution TEM havesuccessfully visualized, at the molecular level resolution, the two manners for producing such curvedlamellar crystals with an edge-on orientation in crystalline thin films of i-PS.
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