FOURIER-TRANSFORM INFRARED STUDY OF UNIAXIALLY ORIENTED ATACTIC POLYSTYRENE

Results of an experimental study are presented which show that infrared measurements of the dichroic ratio of atactic polystyrene absorption bands provide a valuable method of determination of the overall orientation of chains as well as the particular orientation of the trans conformational segments. The orientation process produces the alignment of the chains as well as an increase in the amount of trans conformational segments. A linear relationship is observed between birefringence and dichroic ratio for the absorption bands characteristic of overall orientation. A value of 35 degree plus or minus 3 degree is obtained for the angle between the normal to the plane of the benzene ring and the chain axis from both infrared and birefringence determinations. 14 refs.