The present invention aims to provide a method for surface-modifying a rubber vulcanizate or a thermoplastic elastomer, which is capable of cost-effectively imparting a variety of functions, such as sliding properties and biocompatibility, according to the applications. The present invention relates to a surface modification method for surface-modifying an object of a rubber vulcanizate or a thermoplastic elastomer, the method including: step 1 of forming polymerization initiation points A on a surface of the object; step 2 of radically polymerizing a non-functional monomer, starting from the polymerization initiation points A, to grow non-functional polymer chains; step 3 of forming polymerization initiation points B on the surface of the object where the non-functional polymer chains are formed; and step 4 of radically polymerizing a functional monomer, starting from the polymerization initiation points B, to grow functional polymer chains.

The present invention provides a rubber composition that may improve fracture resistance of the resulting tire while maintaining good drainage performance, and a tire using the same. The rubber composition includes: a rubber component; and a fiber made of a hydrophilic resin. The fiber is formed with a coating layer on its surface. The coating layer is made of a resin having affinity for the rubber component.

The present invention relates to a novel method for conferring to thermoplastic, thermostable polymers or elastomers, magnetic, electromagnetic, electrical, X-ray shielding or density properties that allow the detection of said polymers by means of specific equipment that exists in the prior art. The detection of the thermoplastic polymers, thermostable polymers or elastomers in turn facilitates their location, removal or separation. The method is based on the addition of specific iron and silicon alloys with or without surface treatment.