Equilibrium and Dynamic Dielectric Properties of Acrylate Polymers with (Phenyl)(4-chlorophenyl)methanone Groups in Their Structure

Article abstract of DOI:10.1021/j100034a040

The curves describing the relaxation behavior of poly(4-(acryloxy)phenyl)(4-chlorophenyl)methanone at several frequencies present in the dielectric loss-temperature plane a β relaxation centered at -76 deg C at 10 Hz, whose activation energy shows a slight tendency to increase as the temperature goes up.The relaxation spectra exhibit an ostensible glass-rubber relaxation or α process centered at 106 deg C at 10 Hz, in which free charge conductivity and blocking electrode phenomena become dominant at frequencies below 10 Hz.An electric model is used to separate the dipolar response from conductivity contributions in the glass-rubber relaxation, and the dipole time correlation function for this process is obtained at several temperatures.The intramolecular correlation coefficient g_intra, determined from dielectric measurements in solution, is somewhat larger than the coefficient g involving both intra- and intermolecular interactions, obtained from dielectric measurements in the bulk.A rotational state scheme is developed which gives a good account of the intramolecular dipolar correlation coefficient.Finally whereas the relaxation mechanisms involved in the glass-rubber relaxation seem to be governed by the volume, the conductive processes exhibit Arrhenius behavior.