Thermoplastic elastomer nanocomposites (TPE nanocomposites) based on PA6/ NBR/Cloisite 30B were prepared through a direct melt mixing process in an internal mixer. The effects of NBR content (10, 30 and 50 wt.%) and nanoclay loading (3, 5 and 7 wt.%) on morphology and mechanical properties of the nanocomposites have been studied and compared with unfilled PA6/NBR blends as well. The TPE nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), differential scanning calorimeter (DSC) and mechanical properties. XRD results suggested that the nanoclay is exfoliated into the TPE nanocomposite matrix. TEM image of the PA6/NBR/nanoclay composite showed partial exfoliated structure of silicate layers dispersed through the both NBR and PA6 phases. The SEM photomicrograph of PA6/NBR nanocomposite showed an increasing of the rubber particles size in comparison with unfilled PA6/NBR TPE. By presence of nanoclay, improved modulus of the prepared TPE nanocomposites was achieved. DSC studies showed that loading of the nanoclay reduced the degree of crystallinity of the nanocomposite samples.

In this work, thermoplastic elastomers based on polypropylene (PP) and recycled ethylene-propylene-diene monomer (r-EPDM) blends with polypropylene-graft-maleic anhydride (PP-g-MA) as modifier (0 to 8wt.%) were prepared by melt compounding via twin-screw extrusion followed by injection molding. In particular, the effects of material composition and feeding strategies were studied. The morphological and mechanical properties of the blends were investigated by using scanning electron microscopy (SEM), tensile, flexural, impact, density and hardness tests. The results indicate that good dispersion and compatibility between PP and r-EPDM particles was obtained and that incorporation of r-EPDM leads to significant increase in PP impact strength. Finally, the feeding order of each component in the extruder was found to modify substantially the final morphology of the blend, thus having ad irect influence on their mechanical properties.

In this work, different concentrations (0, 35, 50 and 65%wt.) of recycled rubber (ethylene-propylene diene, EPDM) were blended with virgin polypropylene (PP) to produce thermoplastic elastomer resins via twin-screw extrusion. Then, the samples were pelletized and foamed by injection molding using a chemical blowing agent (azodicarbonamide, ADC). In particular, the molding process was optimized to determine the effect of processing parameters like blowing agent content, mold temperature, and injection conditions (pressure, velocity, etc.). From the samples obtained, a complete morphological (skin thickness, cell size and cell density) and mechanical characterization was performed including density and hardness. The results obtained showed that it is more difficult to produce a good foam structure with increasing recycled rubber content.

In this work, thermoplastic elastomers (TPE) were produced based on polypropylene (PP) and recycled ethylene-propylene-diene monomer (r-EPDM) through twin-screw extrusion followed by injection molding. In particular, the effect of different feeding strategies (component introduction order and position along the screw) and r-EPDM content (0, 20, 35, 50 and 65 %w t.) were studied. From the materials produced, morphological and mechanical characterizations were carried out. The results show that feeding strategy has asubstantial influence on dispersion and compatibility between PP and r-EPDM. The main result is that r-EPDM can significantly increase PP impact strength (495 %) with optimized processing conditions.

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