Origin of an intermediate peak in DMTA analysis of multilayer ABS/PC samples.

Three layers film shaped by thermocompression of acrylonitrile butadiene styrene copolymer and polycarbonate have been analyzed in dynamic mechanical thermal analysis in tensile mode. They present two peaks as the film is loaded perpendicularly to the layers and three peaks as the film is loaded in parallel to the layers. Numerical computations confirm that the origin of this peak is not related to a mechanical issue such as the transmission of the imposed deformation from one layer to the other. Using this method, it is demonstrated that this third peak can only be obtained assuming a material transition with its own behavior between layers. Tan δ measurements provide a simple and useful experimental tool to understand more about the interfacial zone in polymer blends. [ABSTRACT FROM AUTHOR]