The component dynamics and molecular parameters were investigated for miscible poly(4-vinyl phenol)/poly(ethylene oxide) (PVPh/PEO) blends. Global values of molecular weight between entanglements (M-e) were first estimated for the blends and were compared with existing athermal model predictions. Global interchain friction coefficients () of the blends were deduced from the zero-shear viscosity. A maximum was observed at a composition of 20-30 wt % of PEO. Chain dimensions of this phase are estimated by using a relationship between the plateau modulus and a packing length (i.e., number of individual chains present in a given small volume of the melt). A slight increase in M-e is observed at low PEO weight fraction (before 0.20), followed by a sharp decrease in M-e values after this concentration. Values of xi PVPh/PEO blends show a maximum value at 20-30 wt % of PEO. (C) 2004 Wiley Periodicals, Inc.