酚酞基聚芳醚酮增韧改性环氧树脂的结构与性能

Structure and Properties of Phenolphthalein-Based Polyaryl Ether Ketone Toughened Modified Epoxy Resin

针对耐高温环氧树脂韧性低的问题,采用酚酞基聚芳醚酮(PEK-C)增韧改性耐高温环氧树脂。研究了PEK-C相对分子质量和含量对改性树脂的固化反应、增韧效果和耐热性能的影响。结果表明,PEK-C的加入对固化反应、耐热性能的影响较小,但会显著提升环氧树脂的韧性,且在一定范围内,PEK-C的相对分子质量和添加量越大,增韧效果越好。15%相对分子质量为8×104的PEK-C改性树脂具有最佳的力学性能,其拉伸强度和断裂伸长率分别达到了80 MPa和3.1%,较未改性树脂分别提高了68%和121%,冲击韧性高达23.3 kJ/m2,较未改性树脂提升了99%。采用透射电子显微镜表征了不同PEK-C含量改性树脂的微观相结构,结果表明,随PEK-C含量增加,依次观测到了从海岛相到双连续再到相反转的相结构转变。

In view of the low toughness of high temperature epoxy resin,phenolphthalein-based polyaryletherketone(PEK-C) was adopted to toughen and modify high temperature epoxy resin.The effects of the molecular weight and content of PEK-C on the curing reaction,toughening effect and heat resistance of the modified resin were studied.The results show that the addition of PEK-C has little effect on the curing reaction and heat resistance,but it can significantly improve the toughness of the epoxy resin.The 15% PEK-C with the molecular weight of 8×10~4 modified resin has the best mechanical properties,the tensile strength and elongation at break reach80 MPa and 3.1%,respectively,which are 68% and 121% higher than those of the unmodified resin,respectively.The impact toughness is as high as 23.3 k J/m~2,which is 99% higher than that of the unmodified resin.The microphase structures of the modified resins with different PEK-C contents were characterized by transmission electron microscopy(TEM).With the increase of PEK-C content,the phase structure transition from sea-island phase to bicontinuous phase inversion is sequentially observed.