Polyamide 6/clay nanocomposites using a cointercalation organophilic clay via melt compounding

Polyamide 6/clay nanocomposites (PA6CN) were prepared via the melt compounding method by using a new kind of organophilic clay, which was obtained through cointercalation of epoxy resin and quaternary ammonium into Na-montmorillonite. The dispersion effect of this kind of organophilic clay in the matrix was studied by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM); the silicate layers were dispersed homogeneously and nearly exfoliated in the matrix. This was probably the result of the strong interaction between epoxy groups and amide end groups of PA6. The mechanical properties and heat distortion temperature (HDT) of PA6CN increased dramatically. The notched Izod impact strength of PA6CN was 80% higher than that of PA6 when the clay loading was 5 wt%. Even at 10 wt% clay content, the impact strength was still higher than that of PA6. The finely dispersed silicate layers and the strong interaction between silicate layers and matrix decreased the water absorption. At 10 wt% clay content, PA6CN only absorbs half the amount of water compared with PA6. The dynamic mechanical properties of PA6CN were also studied. (C) 2003 Wiley Periodicals, Inc.