PBT弹性体力学性能及低温脆性研究

Mechanical properties and low temperature embrittleness of PBT elastomer

采用一步法制备了热固性3,3-双(叠氮甲基)环氧丁烷-四氢呋喃共聚醚(PBT)弹性体,并对其氢键结构、应力-应变关系和动态力学性能及低温脆性进行了研究。结果表明,合成的PBT弹性体拉伸强度和断裂伸长率在DEG羟基含量为35%、R=0.97时,可达2.51 MPa和1 274%,玻璃化温度为-34.5℃。高DEG含量的PBT弹性体脆化参数较低,与常温力学性能变化规律相反。因此,引入低温脆化参数,对PBT弹性体的性能优化具有积极意义。

The thermosetting PBT elastomer was synthesized using one-step process, and its hydrogen bond structure, stress- strain relationship, dynamic mechanical properties and low temperature brittleness were studied. The results show that the tensile strength and elongation at break reach 2.51 MPa and 1 274%, and the glass transition temperature is -34.5 ℃ for the elastomer containing 35% carboxyl-end group content of DEG.In contrast to the change of mechanical properties at room temperature, the elas- tomer with higher DEG content has lower embrittlement parameters. It has positive significance to optimize the mechanical properties of PBT elastomer by introducing low temperature embrittlement parameter.