PVC-and PC-films doped with various fluorescent molecules were uniaxially drawn below and just above the glass transition temperature. The orientation of fluorescent probes and polymer segments is discussed, comparing Hermans' orientation factors evaluated from birefringence for the segments and from dichroism and fluorescence polarization for the probes. Moreover, the orientation of the fluorescent probes is related to that of hypothetical units, orientated according to the pseudoaffine deformation mechanism.

Atactic polystyrene (PS) is doped in solution with various fluorescent molecules and cast to fdms. Rectangular samples, cut from these films, are uniaxially drawn at 100 ~ and 110 ~ The orientation of the'fluorescent probes is characterized by UVdichroism and fluorescence polarization, that of the polymer segments by IR-dichroism and birefringence. It is observed that the fluorescent molecules depending on their structure tend to orientate more or less perpendicular to the drawing direction. This can be understood by assuming that the benzene rings of the fluorescent probes try to associate to those of the polymer. As consistent values of the angle between the 2850 cm -~ transition moment and the chain axis and of the intrinsic birefringence result 70 ~ and -0.10 respectively.

Bis-phenol-A-polycarbonate (PC) is dyed in solution with fluorescent molecules of different shapes and cast to films. Rectangular samples, cut from these films, are drawn varying draw ratio and drawing temperature. The orientation of the fluorescent probes is investigated by dichroism and fluorescence polarization, that of the polymer segments by birefringence. Hermans' orientation factors obtained by dichroism and fluorescence polarization are in good agreement. Long rodlike fluorescent molecules exhibit greater orientation factors than smaller ones. The correlation between segmental and probe orientation is discussed. Keeping the birefringence constant, the probe orientation factors depend on drawing temperature.

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