Conformational Characteristics of Poly(ethy1 methacrylate). Dipole Moment Measurements and Calculations

ABSTRACT: Dipole moment measurements of poly(ethy1 methacrylate) (PEMA) have been performed in four different solvents, benzene, l,4-dioxane, carbon tetrachloride, and toluene, in a temperature range of about 20-100 "C. Experimental measurements have been theoretically analyzed on the basis of rotational isomeric state formalism. Energetic and geometric parameters proposed for poly(methy1 methacrylate) are found to give a reasonable account of the experimentally measured values, in general. However, the change in average dipoles with temperature is found to exhibit a substantial dependence on the type of solvent, which indicates the importance of specific solvent-polymer interaction on the conformational characteristics of the chain