Temperature dependence of polystyrene Raman depolarization in cyclohexane, methyl ethyl ketone, and deuterobenzene solutions

The depolarization ratio ρ of the 1002 cm−1 band in polystyrene has been measured as a function of temperature (20 < T < 60°CC) in the solvents cyclohexane, methyl ethyl ketone, and deuterobenzene. The largest changes in ρ were observed in the poorest solvent, cyclohexane and no changes were detectable in benzene. The ratio, 〈r2〉/n/2, measured in the same solvents over the same temperature range by conventional light scattering, is compared with the ρ data. The corresponding changes in rotational isomer population are calculated and the dependence of ρ on these populations is demonstrated.