Effects of waste ground rubber tire powder (WGRT) and chemical blowing agent content on the cell morphology and physicomechanical properties of injection‐molded polypropylene/WGRT foams

Microcellular polypropylene (PP)/WGRT blends, a new outlet for the recycling of waste tire rubber, were prepared in an injection-molding process by using a chemical blowing agent. The effects of WGRT content and chemical blowing agent content on the density, cell morphology, and physicomechanical properties of the foamed PP/WGRT blends were investigated. The foam morphologies were characterized in terms of void fraction, average cell size, and cell density. The results indicated that both the WGRT and the blowing agent content had huge effects on the cell morphology and tensile properties of the PP/WGRT foams. J. VINYL ADDIT. TECHNOL., 15:275–280, 2009. a 2009 Society of Plastics Engineers