Dielectric and C-13 NMR relaxation in solutions of the sulphone copolymers and terpolymers of but-2-ene and of but-1-ene.

Abstract

Abstract We describe studies made with a time domain system of the high frequency dielectric relaxation of solutions in chloroform and in dioxane of the polyolefins sulphones of but-2-ene and but-1-ene, and of the terpolymers of intermediate composition. The correlation times for transverse dipole relaxation are compared with the values obtained here or elsewhere by dynamic NMR means for the hydrocarbon segments of the main chain in the same solvents. Solvent viscosity is not an important factor controlling segmental motions. In chloroform the high frequency motions of the chains rich in 1-olefin units have similar dipole and NMR correlation times, which is consistent with the simple helical model of the terpolymers, but in the less polar dioxane a specific solvent effect may sufficiently disrupt dipole ordering to produce a different chain dynamics. The dielectric measurements indicate a wide range of correlation times for dipole movement. Differences between the dielectric and NMR correlation times in the disordered chains may arise from a greater sensitivity of the NMR T1 relaxation process to the high frequency components in the spectral distribution function.