Regularity modes in Raman spectra of polyolefins: Part I. Propylene/olefin copolymers

Behavior of the regularity modes of isotactic polypropylene is analyzed in Raman spectra of a number of random propylene/olefin copolymers. The regularity modes at 809, 841, 973, 998, and 1220 cm−1 decrease in intensity with growth of the content of the incorporated monomer. For the lines at 809, 973, and 1220 cm−1 the rate of intensity damping varies depending on the structure of the incorporated monomer. The type of the incorporated monomer has inconsiderable effect on the evolution of intensity of the regularity bands at 841 and 998 cm−1. Anomalous behavior of the mode at 1220 cm−1 was observed for the propylene/1-butene copolymers.