Water concentration, foaming temperature, nucleation agent concentration, screw speed and die diameter are factors influencing foam forming, cell size and cell distribution. The foam structure was dramatically affected by solid fillers that acted as nucleation agents. The expansion ratio was further reduced with talc concentration, at 2% talc; the foam expansion was almost 3 times smaller than the foam without talc. With a reduction in the expansion ratio by talc, the foam cellular structure was also changed dramatically. Compared with foams without talc, the texture of the foam with talc became uniform and fine. Cell size distribution became narrower as talc content increased from 0.5 to 2.0%.