Structural and rheological properties of different polyamide/polyethylene blends filled with clay nanoparticles: A comparative study

This study mainly aims at showing that the compatibilizing effect of organically modified nanoclay particles in 80/20 polyethylene (PE)/polyamide (PA) immiscible blends with nodular morphology, is strongly influenced by the rheological behavior and molecular characteristics of both polymers. Four PE/PA blend couples, based on two polyethylenes and two polyamides with different molecular characteristics and properties, were filled at various clay fractions and investigated using SEM, TEM, XRD and rheometrical techniques. The results show that there is no compatibilizing effect of clay when a high viscosity polyamide and/or a low viscosity polyethylene are used. The role played by the molecular characteristics of both polyamide and polyethylene chains in the structure and properties of the interphase was discussed. At last, the viscoelastic properties of PE/PA blends were shown to be significantly influenced by clay addition and content, through various mechanisms which involve changes in dispersed phase interfacial area, in blend morphology, in clay localization and in interphase structure.