Phase Structure of Polyamide 6/Poly(styrene-co-acrylonitrile) and Poly(styrene-b-(ethylene-co-butylene)-b-styrene) or Poly(maleated Styrene/Ethylene-co-Butylene/Styrene) Ternary Blends

Two sets of ternary blends; polyamide 6/poly(styrene-co-acrylonitrile)/poly(styrene-b-(ethylene-co-butylene)-b-styrene) (PA6/SAN/SEBS) and polyamide 6/poly(styrene-co-acrylonitrile)/poly(maleated styrene/ethylene-co-butylene/styrene) (PA6/SAN/SEBS-g-MA), based on 70 wt% of matrix and 30 wt% of the dispersed phases at various concentrations of the minor components, were prepared via melt blending. Morphologies of the ternary systems were studied using scanning electron microscopy (SEM) and compared with the predictions of the spreading coefficient (SC), minimum relative interfacial energy (RIE), and dynamic interfacial energy (DIE) phenomenological models. The effects of different reported surface tensions of the used polymers and different protocols of the core-shell ratio calculation on the prediction of the models were investigated. The core-shell structure for PA6/SAN/SEBS system and two separate minor phases for PA6/SAN/SEBS-g-MA were observed at all of the compositions. The results indicated that the most important parameter for the accurate prediction of the models is the accurate calculation of the interfacial tension of the used polymers, in both the static and dynamic conditions.