Abstract: The present invention relates to a crosslinkable rubber composition, the use thereof, the rubber grains formed therefrom, and a method for preparing and injection molding the rubber grains. The crosslinkable rubber composition includes at least a styrene butadiene copolymer, a softener for rubber, a flow modifier and a peroxide vulcanizing agent. The crosslinkable rubber composition is suitable for being made into rubber products. It can be made into rubber grains that will not crosslink below a temperature of 80° C. The rubber grains are formed through internal mixing, open mixing and pelleting extrusion. The rubber composition and the rubber grains of the present invention can be formed directly by injection molding and kept at room temperature over a long period of time.