Morphology, structure and lattice defects in thin films of syndiotactic polystyrene

The morphologies developed during crystallization of syndiotactic polystyrene (sPS) in thin films, were investigated by transmission electron microscopy (TEM) and electron diffraction. Special emphasis was put on the diffraction contrast, which is very sensitive to crystal defects. While the defocus contrast gives an overall picture of the morphologies, the darkfield diffraction contrast may image lattice defects such as dislocations, stacking faults, and ordered domains, among others. Three different morphologies were found: Single‐crystal‐like morphologies. Edge‐on stacked lamellar morphologies. Spherulitic morphologies. Due to different imaging conditions for those morphologies in the dark‐field imaging mode, different types of lattice defects were detected. Because the dark‐field images are not a direct visualization of the defects, the nature of the contrasts is discussed with respect to the disorder of the molecules creating the defects.