MODIFIED NATURAL RUBBER, METHOD FOR PRODUCING SAME, RUBBER COMPOSITION, AND TIRE

The present invention provides a modified natural rubber that offers higher efficiency of graft polymerization or attachment of a polar group-containing compounds, and that possesses excellent low loss factor, wear resistance and fracture resistance when used as a rubber composition, a rubber composition using the modified natural rubber and a tire using the rubber composition. In the present invention, a polar group-containing compound is graft polymerized or attached under mechanical shear force to a natural rubber raw material having a nitrogen content of 0.4 mass% or less.