DIELECTRIC BEHAVIOR OF N-BUTYL ACRYLATE DURING POLYMERIZATION REACTION

The dielectric behavior of n-butyl acrylate undergoing a thermally ini tiated polymerization reaction was analyzed in the 0.1-10 GHz frequenc y interval by means of time domain reflectometry. The dielectric behav ior of the system was modeled by a superposition of two main relaxatio n processes, related to monomer and polymer, respectively. The time ev olution of the dielectric permittivity of the reacting system at diffe rent frequencies is discussed. It is shown that the change of the diel ectric permittivity at about 10 GHz is mainly due to the disappearance of the monomer. The presence of a secondary relaxation in the polymer was detected at 160 K in the frequency domain (10(3)-10(7) Hz) by imp edance spectroscopy.