Drawing and orientation development of aromatic polyesters containing terphenyl units in the main chain and aliphatic side chains

A range of aromatic polyesters containing terphenyl units in the main chain and alkyl side chains have been investigated with respect to their structure and orientation development. As-cast films showed a layered structure: layers of the main chains were preferentially organized parallel to the film surface. Upon drawing of these films, the structure changed to a fibre-symmetric one, as was proven by wide-angle X-ray diffraction (WAXD). Possible morphologies, which are based on WAXD and Raman data, are proposed. The development of the orientation with draw ratio appeared to be extremely efficient, even more efficient than that according to the affine deformation model. This was explained by the fact that the affine model assumes thin rods, whereas in reality, the orientation of units with a considerable thickness takes place. Copyright (C) 1996 Elsevier Science Ltd.