Optical Anisotropies of Model Analogues of Polycarbonates

Abstract

Depolarized light scattering and electric birefringence have been used to evaluate the optical anisotropy tensors for dimethyl carbonate, methyl phenyl carbonate, diphenyl carbonate, and 2,2-diphenylpropane. Rotational potentials about the phenyl axes in diphenyl carbonate and in diphenylpropane are estimated from force field calculations of interactions between nonbonded atoms. Rotations of the same sign ≈ ∣46°∣ of the phenyl groups in diphenylpropane and uncorrelated rotations ≈ ∣46°∣ about carbonate bonds are indicated. By combination of the information on structure, anisotropy, and conformation of these model compounds, the optical anisotropy tensors for carbonate and phenyl groups are estimated for these analogues of units occurring in the polycarbonate chain. © 1982, American Chemical Society. All rights reserved.