Abstract: Al2O3 was extracted from fly ash via high-temperature alkali calcinations. The properties of PP containing such extracted Al2O3 were compared with commercial PP/Al2O3 resins. It showed that, the tensile and impact properties of PP/extracted Al2O3 were similar to commercial resins. When the content of the extracted Al2O3 increased to 2 %, the microstructure of PP matrix change from smooth structure to slight lamellar structure, and the tensile strength, elongation at break, and impact strength increased by 6 %, 23 %, and 14 %, respectively, based on neat PP. However, when the content of extracted Al2O3 increased to 5%, the impact strength of PP decreased dramatically.

Key words: Fly ash, aluminum oxide, polypropylene, modification