Dispersão seletiva de argila montmorilonita em blendas poliméricas de PA6/ABS

Abstract

For some applications toughening of polyamide is important. This can be accomplished through the addition of an elastomeric phase to the polyamide matrix with the drawback of a reduction in the stiffness and strength of the material. Several studies lately have focused on the modification of polyamide matrix with the purpose of obtaining a balance between toughness and stiffness for these thermoplastics. In this work, to achieve a balance between stiffness and toughness, ternary nanocomposites based on blends of polyamide 6 (PA6) and acrylonitrile-butadiene-styrene (ABS) were prepared by the melt blending processes using the organoclay Cloisite® 30B (OMMT) and the styrene-maleic anhydride copolymer (SMA) as compatibilizer. Four blending sequences were used to prepare the selected systems and their mechanical properties studied through the Young s modulus and notched Izod impact properties. The addition of organoclay increases the Young s modulus of all ternary nanocomposites when compared to the blend and the PA6 matrix. This fact was attributed to preferential location of the clay in the PA6 matrix phase. The micrographs obtained by transmission electronic microscopy (TEM) indicate that the nanoclay shows an exfoliated structure and reside in the PA6 matrix phase, as well as in the interface between the phases. PA6/ABS/OMMT ternary nanocomposites with different content of nanoclay (1, 3 and 5%) were studied and it was observed that the particles size of ABS dispersed phase decrease with the increase of the OMMT content in the blend. This fact indicates that nanoclay can play an important role to prevent the coalescence in the ABS domains during the melt state processes. PA6/ABS ternary blends compatibilized with SMA were prepared by melt state process and it was observed that the mechanical properties and the morphology were influenced by the blending sequence of the components.