The present invention provides a thermoplastic polyester elastomer excellent in heat resistance, heat-aging resistance, water resistance, light resistance, low-temperature property and the like, and further excellent in block order-retaining ability, the thermoplastic polyester elastomer comprising a hard segment which comprises polyester constituted with aromatic dicarboxylic acid and aliphatic or alicyclic diol and a soft segment which comprises mainly aliphatic polycarbonate, wherein the hard segment and the soft segment being connected, and wherein when melting points of the thermoplastic polyester elastomer are obtained by measuring on a differential scanning calorimeter in three cycles in which a temperature is raised from room temperature to 300°C at a heating rate of 20°C/min., maintained at 300°C for 3 minutes and lowered to room temperature at a cooling rate of 100°C/min., a melting point difference (Tm1-Tm3) between a melting point obtained in the first cycle (Tm1) and a melting point obtained in the third cycle (Tm3) is 0-50°C, and a tensile strength at break is 15-100 MPa.
本发明提供了一种热塑性聚酯弹性体,具有优异的耐热性、耐热老化性、耐
水性、耐光性、低温性能等,并具有优异的嵌段保持能力,该热塑性聚酯弹性体包括硬段(由芳香族二
羧酸和脂肪族或脂环族二元醇构成的聚酯组成)和软段(主要由脂肪族聚
碳酸酯组成)、热塑性聚酯弹性体的熔点是在差示扫描量热计上以 20°C/min 的升温速率从室温升至 300°C 的三个循环中测量得到的。,在第一个循环中获得的熔点(Tm1)与第三个循环中获得的熔点(Tm3)之间的熔点差(Tm1-Tm3)为 0-50°C,断裂拉伸强度为 15-100 兆帕。