Study on the microstructures and mechanical behaviour of compatibilized polypropylene/polyamide-6 blends

A series of blends of polypropylene (PP)-polyamide-6 (PA6) with either reactive polyethylene-octene elastomer (POE) grafted with maleic anhydride (POE-g-MA) or with maleated PP (PP-g-MA) as compatibilizers were prepared. The microstructures and mechanical properties of the blends were investigated by means of tensile and impact testing and by scanning electron microscopy and transmission electron microscopy. The results indicated that the miscibility of PP-PA6 blends was improved with the addition of POE-g-MA and PP-g-MA. For the PP/PA6/POE-g-MA system, an elastic interfacial POE layer was formed around PA6 particles and the dispersed POE phases were also observed in the PP matrix. Its Izod impact strength was four times that of pure PP matrix, whilst the tensile strength and Young's modulus were almost unchanged. The greatest tensile strength was obtained for PP/PA6/PP-g-MA blend, but its Izod impact strength was reduced in comparison with the pure PP matrix.