PBT弹性体力学性能及低温脆性研究

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。

Mechanical properties and low temperature embrittleness of PBT elastomer

The thermosetting PBT elastomer was synthesized using one-step process,and its hydrogen bond structure,stressstrain 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 elastomer 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.