将聚对苯二甲酰己二胺(PA6T)在20、90、150℃水浴中进行湿热老化处理,对不同老化时间材料物理和力学性能进行了表征.结果表明,随着处理时间的延长,PA6T的吸水率逐渐增大;而随着温度的升高,PA6T的扩散系数及平衡吸水率均增加;20℃和90℃时PA6T未发生明显降解,而150℃时PA6T降解导致相对分子质量减小;水分子的增塑作用增强了分子链活动性,提高了冲击强度,结合水分子与酰胺键之间的强氢键作用导致拉伸模量升高.%A hygrothermal aging experiment was conducted for polyhexamethylene terephthalamide (PA6T)at 20,90 and 150 ℃,and effect of aging time on physical and mechanical properties of PA6T specimens was investigated.The results indicated that water absorption of PA6T increased with an increase of aging time,and its diffusion coefficient and equilibrium moisture absorption were also improved as the aging temperature increased.There was no change in intrinsic viscosity observed from of PA6T specimens at 20 and 90 ℃.However,the intrinsic viscosity decreased evidently at 150 ℃because of the hydrolysis of PA6T.The impact strength of PA6T was enhanced due to the increase of activity of its molecular chains.Furthermore,hydrogen bonding between water and amide groups led to an increase in tensile modulus.
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