CONICET | Buscador de Institutos y Recursos Humanos

In recent years polymer/layered silicate (PLS) nanocomposites have attracted great interest, both in industry and in academia, because they often exhibit remarkable improvement in materials properties when compared with virgin polymer or conventional micro and macro-composites. These improvements can include higher moduli, increased strength and heat resistance, decreased gas permeability and flammability, and increased biodegradability of biodegradable polymers. However these properties are strongly influenced by how the clay is dispersed in the polymer. In this study the synergistic effects in PP + short glass fibre (SGF) + nanoclay systems in the tribogical and dynamic properties in injection mouldings were analysed. The materials used were a polypropylene homopolymer, nanoclay (montmorillonite layer silicate) for polyolefin nanocomposites in percentages of 2%, 6% and 10%, and a polypropylene homopolymer with content of 10% and 30% of glass fibre reinforcement, allowing the determination of the actual coefficient of friction. Additionally a mixture of PP with 10% of SGF and 2 % of nanoclay, and PP with 30% of SGF and 2% of nanoclay, were processed. The various materials systems were characterised in terms of dynamic mechanical properties and tribological properties. Several tests were conducted which includes the measurements of friction resistance in conditions similar to the ejection phase in injection moulding process. The microstructure of the mouldings was characterised by polarized light microscopy and DSC. The moulding properties are determined by the incorporation of nanoclay and SGF, and by the processing conditions. Moreover, they were also observed the influence on the microstructure of the mouldings and the synergistic effect of the nano- and micro-reinforcements.