Raman Spectra of Polyethylenes

摘要

Raman spectra of normal and deuterated polyethylenes in the solid and liquid states were obtained. Tentative assignments for (CD2)nare made using the Tellermdash;Redlich product rule and Krimm's isotopic frequency rule. Interactions between the CD2deformation and the symmetrical Csngbnd;C stretching modes of speciesAg,and between the CD2wagging and the asymmetrical Csngbnd;C stretching modes of speciesB2g, are considered. Depolarization ratios for melt spectra successfully identified the symmetric modes only in the neighborhood of the CH2stretching bands of (CH2)n. The Raman spectrum of molten (CH2)nincludes bands at 1080 and 1303 cmmdash;1, at which frequencies ``amorphous'' bands are observed in the infrared spectrum of the solid.