Morphology of nylon 6/polypropylene blends compatibilized with maleated polypropylene

Abstract

Abstract Transmission electron microscopy (TEM) was used to examine the morphology of blends of nylon 6 and polypropylene (PP) containing various maleated polypropylenes (PP‐g‐MA). The size of the dispersed polypropylene particles decreases as the content of maleic anhydride in the PP‐g‐MA increases for binary blends of nylon 6 and the maleated polypropylenes. Ternary blends of nylon 6, PP, and PP‐g‐MA show morphologies that depend on the content of maleic anhydride of the PP‐g‐MA and on the miscibility of PP and PP‐g‐MA. Blends where PP and PP‐g‐MA are immiscible show a bimodal distribution of particle sizes. Miscibility of the PP and PP‐g‐MA was determined by TEM using a special staining technique. Experimental observations of miscibility were further corroborated by thermodynamic calculations. The morphology of the ternary blends was also found to be dependent on the ratio of PP/PP‐g‐MA. By changing this ratio it was possible to induce drastic changes of morphology, going from a continuous nylon 6 phase to a continuous PP phase at a fixed composition. The mechanical properties of these blends were found to be dependent on their morphology. ©1995 John Wiley & Sons, Inc.