The role of nanotalc fillers as compatibilizers of PP/PA6 blends: thermal and mechanical properties
Résumé
New layered synthetic nanotalc prepared at a lab-scale by a conventional hydrothermal process and a commercially available natural fine talc (Luzenac© A3) were chosen in order to establish a comparative study in terms of their contributions on the improvement of the final properties of PP/PA6 blends prepared using an extrusion process [1, 2] . In this work, we highlighted that the addition of synthetic talc fillers induces a significant decrease of the size of the polyamide 6 domains. These results confirm the role of talc as compatibilizer of polymer blends (Figure 1). Compared to natural talc, a high level of dispersion of talc layers in PA6 phase was obtained with the synthetic nanotalc which is more hydrophilic. SEM/EDS microanalysis of ternary PP/PA6/talc blends confirmed these observations and suggested that the talc particles have an exclusive preference to interact with the minor PA6 phase than the continuous PP matrix. In addition, the incorporation of synthetic nanotalc greatly improves the thermal stability of PP/PA6 blends. In fact, an increase of 23 °C and 11 °C in the onset temperature of degradation were observed in the presence of synthetic and natural talc respectively. In terms of mechanical properties, the better dispersion of synthetic talc fillers led to higher Young Modulus (+39%) compared to the natural talc one (+14%). Synthetic talc can be considered as a new promising filler with nanoscale features that can induce better performance than ones got with natural talc. References [1] A. Dumas, F. Martin, C. Le Roux, P. Micoud, S. Petit, E. Ferrage, J. Brendlé, O. Grauby, M. Greenhil-Hooper, Physics and Chemistry of Minerals 40 (2013) 361. [2] M. Yousfi, S. Livi, A. Dumas, C. Le Roux, J. Crépin-Leblond, M. Greenhill-hooper, J. Duchet-Rumeau, Journal of Colloid and Interface Science. In press. DOI: 10.1016/j.jcis.2013.04.019. Acknowledgement This work was supported by financial funding from National Agency for Research (France) in the frame of the project "Nanotalc" ANR-09-MAPR-0017. The authors acknowledge Dr Annie Rivoire from Claude Bernard University for his help in microscopy experiments.