Study on Extruded Polypropylene Foam

Extruded polypropylene foam with low open cell content, high cell density, small and uniform cell size was prepared via blending conventional linear polypropylene with a small amount of high melt strength polypropylene (HMSPP). Effects of the nature and particle size of the nucleating agent on the cell density and cell size were studied via SEM analyzing. When the content of nucleating agent talc was 1 % , the particle size was 5 μm, using AC as the blowing agent; the obtained foam gave a cell density of 5. 331×106 cells/cm3, and a cell size of 93 μm. It was also found that higher screw rotating speeds favored the uniformity of the foam structure.