An attempt has been made in this study to modify the crumb rubber powder (CRP) surface with maleic anhydride (MA) and thereby improving its adhesion with waste polypropylene (WPP) after melt blending. The modification results in grafting of CRP onto the WPP matrix. The mechanical strength properties of the surface modified CRP-WPP blends increased. This implied improved interaction between WPP and CRP. The increase in decomposition rate as well as the decrease in viscosity under processing conditions for the blends indicates the formation of a copolymer interface between WPP and CRP as a result of CRP modification. A smooth and stable morphology was also found in case of blends of WPP with modified CRP.