Rayleigh-Brillouin light-scattering study of atactic polyethylmethacrylate (PEMA)

Abstract
Rayleigh‐Brillouin light‐scattering studies have been carried out on atactic polyethylmethacrylate thermally polymerized under vacuum from extremely clean monomer. The scattered intensity ratio for the VV polarization geometry varies from 2 (at high temperatures) to 5 and appears to be a function of T−1 with a broad discontinuity in the temperature range 40–70 °C. Depolarization intensities have also been measured and, in particular, it is found that ρH equals unity. These results agree with those previously obtained for polybutylmethacrylate and are also compared with reports on polystyrene. Other characteristics of this glass are discussed.