The effect of the connectivity of an elastomer in a blend of two polyolefins was studied. Blends of natural rubber (NR) with high density polyethylene (HDPE) and polypro- pylene (PP) were prepared using a Banbury mixer at 1808C. The samples were laminated by compression molding at 1808C and quenched in water at room temperature. Extrac- tion of the natural rubber was performed for blends containing equal relative amounts of both polyolefins. The percolation of the rubber within the matrix of both polyolefins started to occur at about 20% rubber content. Mechanical properties, such as Young’s modulus and stress at break, showed the effect of the percolation phenomenon.