We have investigated the influence of different amounts of symmetric block copolymers such as poly(styrene-b-methyl methacrylate) on the form and interfacial relaxation times of a polymer blend containing mainly 7.5% polystyrene as a dispersed phase in a poly(methyl methacrylate) matrix. Special emphasis was put on the investigation of the effect of the compatibilizer molecular weight on these times. For this purpose, we combined predictions of the extended Palierne model with assumptions on the changes of interfacial tension with the amount of compatibilizer. It turned out that the identification of the interfacial modulus in Palierne's model with the Gibbs elasticity modulus as the intrinsic property of a surfactant-laden interface, responsible for the reconstitution of an equilibrium surfactant distribution, is the key point for a quantitative understanding of the ongoing processes and the interfacial relaxation time scaling. On the basis of the assumption that Gibbs elasticity is the important interfacial parameter, the scaling relation for the interfacial relaxation time was derived. A similar treatment of the form relaxation times leads to a more complex scaling relation that is determined by the same set of parameters.