CONFORMATIONAL AND EXPERIMENTAL STUDIES ON THE DIPOLE-MOMENTS OF MODELS OF COMB-LIKE POLYMERS

The synthesis and radical polymerization of 2,2-bis[4-(2-hydroxyethoxy )phenyl]propy monoacrylate are described. The values found at 50 and 6 0 degrees C for the rate constants ratio, k(p)/k(t)(1/2), are similar to those reported for some acrylic polymers with short side groups at the same temperatures although conflicting results are obtained by com parison with the kinetic constants reported for other similar acrylic monomers. The experimental value of the mean-square dipole moment per repeating unit of the resulting polymer poly{2,2-bis[4-(2-hydroxyethox y)phenyl] monoacrylate} was 7.24 D-2 at 30 degrees C. This result is v ery close to the value of 1.83 D-2 found; at the same temperature, for the model compound of the side group of the polymer, 2,2-bis[4-(2-hyd roxyethoxy)phenyl]propyl monoacetate. Owing to the wide distribution o f dipole moments associated with the side groups, the dipolar correlat ion coefficient of the chains was calculated by combining matricial pr oducts of the rotational isomeric state model and Monte Carlo techniqu es. The calculations suggest that the statistics of long side groups r ather than the statistics of the main chain govern the dipolar correla tion coefficient of atactic comblike polymers.