Simulation and experimental study of the pressure-controlled sequential sandwich transfer molding of two SBR rubber compounds under isothermal condition have been carried out to obtain a two-layered sandwich structure. One SBR compound, which is intended for the skin material, is first laid up in the cavity. Then, another SBR compound, intended for the core material, is transferred to penetrate into the skin material and to push the lay-up to fully fill the cavity, resulting in an encapsulated skin/core sandwich structure. Two cases involving different material combinations with different viscosity ratios have been studied. The rheological interaction of the skin/core components and its effect on the penetration behavior and interface shape have been investigated. The influence of processing conditions, such as the volume fraction transferred and pressure, is discussed. The penetration and encapsulation behavior, and the interface development are found to be significantly affected by the rheological properties of the compounds and the volume fraction transferred. However, at a constant volume fraction transferred, the pressure imposed during transfer molding is found to have a little effect on the interface development. These experimental findings are in good agreement with the present predictions based on the model and simulation proposed in Part I of this study.
Available at: http://works.bepress.com/avraam_isayev/156/