短玻纤增强尼龙10T复合材料的热氧老化性能

通过熔融共混法制备短玻纤增强尼龙10T(SGF/PA10T)复合材料,采用DSC、DMA、红外光谱、力学测试等表征方法对240℃下SGF/PA10T的热氧老化性能进行研究。结果表明:热氧老化使SGF/PA10T的初始结晶温度有所增加,玻纤与PA10T基体之间的界面作用减弱,阻尼性能下降;随着热氧老化时间的延长,复合材料的玻璃化转变温度先增加后减小,通过Arrhenius方程对SGF/PA10T发生玻璃化转变时的活化能进行计算,结果进一步证明热氧老化影响分子链的活动能力,并且PA10T分子链在老化初期发生微交联;同时热氧老化显著降低SGF/PA10T的力学性能,当老化天数为50d时,拉伸强度、弯曲强度和缺口冲击强度保持率分别为18.4%,9.8%和37.7%。

T hermal-oxidative Aging Properties of Short Glass Fiber Reinforced Nylon 10T Composites

Short glass fiber reinforced polyamide 10T (SGF/PA10T ) composites were prepared by melt blending method ,and the thermal-oxidative aging properties of SGF/PA10T composites at 240℃were characterized by differential scanning calorimetry (DSC) ,dynamic mechanical thermal analysis (DMA) ,FT-IR and mechanical properties test .The results show that the crystallization onset tem-perature of SGF/PA10T increases ,the interfacial interaction between glass fiber and PA10T matrix is weakened ,and damping capacity decreases during the thermal-oxygen aging process . With the in-crease of thermal-oxygen aging time ,the glass transition temperature increases first and then decrea-ses .Arrhenius equation was used to determine the glass transition activation energy of SGF/PA10T , and the results show that the mobility of molecular chain is changed and PA10T molecular chains are slight cross-linked in preliminary aging stage .At the same time ,the thermal-oxygen can significantly reduce the mechanical properties of SGF/PA10T composites ,after age at 240℃ for 50d ,the tensile strength ,flexural strength and impact strength retention rates are 18 .4% ,9 .8% and 37 .7% respec-tively .