| 摘要 |
A thermoplastic polymer composition has good flexibility, lightweight properties, moldability, and heat resistance, and in particular, is excellent in wear resistance. The thermoplastic polymer composition includes: at least one block copolymer (a) selected from among an ±-methylstyrene based block copolymer having a number average molecular weight of 30,000 to 500,000 and a hydrogenated product thereof, the ±-methylstyrene based block copolymer including a polymer block A mainly composed of an ±-methylstyrene unit and a polymer block B mainly composed of a conjugated diene unit; a propylene-based polymer (b); and an ethylene-based polymer (c) having a density of 0.94 g/cm 3 or less, in a ratio satisfying the following inequalities (1) and (2): 0.1 ‰¤ W a / W a + W b + W c ‰¤ 0.8 1 ‰¤ W b / W c
wherein W(a), W(b), and W(c) represent the masses of the block copolymer (a), the propylene-based polymer (b), and the ethylene-based polymer (c), respectively. |
