Polyamide 66/Clay Nanocomposites via Melt Intercalation

Polyamide 66/clay nanocomposites (PA66CN) were prepared via a melt compounding method using a new kind of organophilic clay, which was obtained through co-intercalation of epoxy resin and quaternary ammonium into Na-montmorillonite. The dispersion effect of silicate layers in the matrix was studied by means of XRD and TEM. The silicate layers were dispersed homogeneously and nearly exfoliated in the matrix as a result of the strong interaction between epoxy groups and PA66. The mechanical properties and heat distortion temperature (HDT) of PA66CN increased dramatically. The notched Izod impact strength of PA66CN was 50% higher than that of PA66 when the clay loading was 5 wt.-%. Even at 10 wt.-% clay content, the impact strength was still higher than that of PA66. The finely dispersed silicate layers and the strong interaction between silicate layers and the matrix reduced the water absorption, at 10 wt.-% clay content; PA66CN only absorbs 60% water compared with PA66. The addition of silicate layers changed the crystal structure in PA66CN.