POLYMER COMPOSITION, CROSSLINKED POLYMER, AND TIRE

A polymer composition is provided that is suitable for manufacturing a tire that not only has excellent low-loss properties and wear resistance, but also has an excellent balance of wet grip performance and mechanical characteristics. A polymer composition according to the present invention is characterized by containing a diene polymer (A) and a filler (B), the diene polymer (A) containing the polymer (A1) and the polymer (A2) described below. Polymer (A1): A copolymer of a polymer of a conjugate diene compound or the conjugate diene compound, and an aromatic vinyl compound, the copolymer being modified with a polar group having affinity for the filler (B), wherein the aromatic vinyl content is 25 mass% or less, and the modification rate is 30-100%. Polymer (A2): A copolymer of an aromatic vinyl compound and a conjugate diene compound including 1,3-butadiene, wherein the aromatic content is 30-50 mass%, the vinyl content is 5-30 mass%, and the peak molecular weight of the polystyrene equivalent measured using gel permeation chromatography is 400,000 to 2,000,000.