This study aims at investigating and characterizing the interphase in Polyethylene (PE)/Polyamide (PA) blends with nodular morphology, filled with organically modified Montmorillonite (C30B), using structural and rheological experimental techniques. PE/PA/C30B blends have been prepared by simultaneous mixing at a dispersed phase fraction (PE or PA) of 20% and a clay fraction ranging from 1 to 6%. Structural properties of the interphase have been investigated using XRD combined with TEM micrographs. The presence of numerous interphase defects is evidenced, and the effect of interphase disorder is discussed. Linear viscoelastic properties show the contribution of the interphase in PE matrix ternary blends at all clay fractions, whereas interphase effects are masked by the contribution of dispersed nanoclay particles in PA matrix ternary blends. (C) 2012 Elsevier Ltd. All rights reserved.