POE-g-MAH对玻纤增强高温尼龙复合材料力学性能的影响

采用双螺杆挤出机制备基于尼龙6T/66 (PA6T/66)和PA10T的玻纤增强高温尼龙(PA)复合材料,玻璃纤维的质量分数为20%。研究了增韧剂马来酸酐接枝乙烯–辛烯共聚物(POE-g-MAH)对复合材料力学性能的影响,并与玻纤增强PA66复合材料体系进行对比。研究结果表明:在高温PA体系中,随着POE-g-MAH含量的增加,拉伸强度和弯曲强度先上升后下降,对PA6T/66体系,POE-g-MAH添加量为5%时增强效果最优,拉伸强度和弯曲强度的提高比例分别为19%和15%,对PA10T体系,POE-g-MAH添加量为15%时增强效果最优,拉伸强度和弯曲强度的提高比例分别为25%和20%;而在PA66体系中,随POE-g-MAH含量的增加,拉伸强度和弯曲强度均下降。通过毛细管流变和扫描电镜的分析以及加偶联剂实验的数据,证实POE-g-MAH在玻纤增强高温PA体系中起到了界面相容剂的作用,增强了玻纤与高温PA树脂基体的相容性。高温PA较高的加工温度造成玻纤表面的偶联剂的降解损失是导致POE-g-MAH在该体系中产生增强效果的原因,并且增强效果最优时的POE-g-MAH添加量与不同高温PA的加工温度直接相关。

Effect of POE-g-MAH on Mechanical Properties of Glass Fiber Reinforced High Temperature Polyamide Composites

The PA6T/66 and PA10T-based glass fiber reinforced composites were prepared by twin-screw extruder(the mass fraction of glass fiber was 20%)and the influence of the toughing agent maleic anhydride grafted ethylene-1-octene copolymer(POEg-MAH)on mechanical properties of the composites were studied.The results show that the tensile strength and flexural strength first increase and then decrease with the POE-g-MAH content for semi-aromatic polyamide composites,compared with the continuous decline of these two strength properties for PA66 composite.For PA6T/66 composite,its tensile strength and flexural strength could be improved by 19%and 15%respectively when the optimal amount of POE-g-MAH about 5%is added.For PA10T composite,its tensile strength and flexural strength could be improved by 25%and 20%respectively when the optimal amount of POE-g-MAH about 15%is added.With the rheology data,scanning electron microscop morphology observation and the experiment of adding the coupling agent,it is tested and verified that in glass fiber reinforced semi-aromatic polyamide composites,the POE-g-MAH acted as the interfacial compatilizer to strengthen the bonding of polyamide resin and glass fiber.Degradation of coupling agent on the surface of glass fiber caused by the rather high processing temperature of semi-aromatic polyamide is the reason why POE-g-MAH could have the strengthening effect in these systems,and the POE-g-MAH content for optimal strengthening effect is directly related to processing temperature of different semi-aromatic polyamide.