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

Dipole moment measurements of poly(ethyl methacrylate) (PEMA) have been performed in four different solvents, benzene, 1,4-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(methyl 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.