The purpose of this work was to study the effect of carbon black (CB) surface state on the interaction between CB and polymer matrix, as well as the polymer chain mobility. The mobility of polymer chain absorbed on the CB surface was estimated by using a dynamic mechanical analyzer and an impedance analyzer. The interaction parameter (B) and immobilized polymer layer thickness (DeltaR) were estimated from the dynamic mechanical analysis. It was observed that values of B and DeltaR decreased with increasing fluorine content on the CB surface. On the other hand, from the dielectric measurement, the Maxwell-Wagner-Sillars (MWS) relaxation peak, accompanied by migration of the charge carriers, accumulated at the interface between polymer and CB, observed at temperatures higher than the glass-transition temperature (T-g) of the polymer matrix. The activation energy (E-a MWS), calculated from the relaxation frequency of MWS relaxation, was decreased with increasing surface fluorine content. Good agreement was found between the B and the DeltaR values estimated from the dynamic mechanical analysis and the E-a MWS calculated from the MWS relaxation frequency estimated from dielectric measurement. (C) 2004 Wiley Periodicals, Inc.