ABSTRACT:The influence of the degree of crystallinity and the syndiotacticity on the 1145, 1095, and 916 cm Ϫ1 bands was studied. The intensity of the 1145 cm Ϫ1 band increased with increasing syndiotacticity at a low degree of crystallinity and with an increasing degree of crystallinity for a sample with syndiotacticity. The intensity of 1095 cm Ϫ1 band increased with increasing syndiotacticity at a fixed degree of crystallinity and was independent of the degree of crystallinity for a sample. The intermolecular hydrogen bonds were found to play an important role. The differences of the relations between the absorbance ratio D 1145 /D 1095 and the degree of crystallinity with syndiotacticity were explained. The extent of the decrease of the intensity of 916 cm 0.327 for the films heated at 50°C with use of a syndiotactic diad content obtained from NMR spectra.