In order to address this issue, we have chosen a fully amorphous polyamide as a matrix for the production of model nanoclay-based polymer nanocomposites that lack the morphological complexities associated with their semi-crystalline analogs. In particular, we report on the successful twin-screw extrusion and injection molding of systems based on Grilamid TR 90 in combination with Cloisite 30B using realistic, industrial-scale processes and equipment.
Structural analysis of these systems (SAXS, WAXS, TEM) confirms high levels of clay dispersion, consistent with the known compatibility of this nanoclay with polyamides in general. Thermal analyses (TGA, DSC) are used to confirm the clay content and the amorphous character of these materials. Finally, we present DMA data, simultaneous tensile testing / thermal imaging results, and SEM-EDS analyses of the rupture faces in order to shed light on the reinforcement mechanisms active in these systems, and draw comparisons with their semi-crystalline counterparts.
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