DIELECTRIC RELAXATIONS OF POLY(FLUOROALKYL METHACRYLATE)S AND POLY(FLUOROALKYL ALPHA-FLUOROACRYLATE)S

Dielectric relaxation studies were made on two homologous series of poly(fluoroalkyl methacrylate) (PFM) and poly(fluoroalkyl alpha-fluoroarylate) (PFF). In both series there were observed alpha above T(g) and gamma relaxations below T(g), which are assigned to reorientational motion of long segments and local molecular motion of fluoroalkyl side groups, respectively. As the length of the fluoroalkyl side groups are longer, the alpha relaxation gradually shifted to lower temperatures and the gamma relaxation rapidly moved to higher temperatures, being very consistent with the well-known results in the homologous series of poly(alkyl methacrylate). However, the alpha relaxation was much larger in PFF than in PFM, which was explained by the polar nature of the alpha-C-F bond in the main chain, while the magnitude of the gamma relaxation was affected sensitively by the polarity of the fluoroalkyl side groups.