不同纤维织物/乙烯基酯复合材料的湿热老化

本文将不同纤维织物与750HOI环氧乙烯基酯树脂复合成三种层合结构的复合材料,对比研究了树脂浇铸体及复合材料在60℃与90℃去离子水中的湿热性能。通过材料的吸湿特性、弯曲性能、微观结构以及动态热机械性能的变化,分析了材料的湿热老化机理。研究表明:不同纤维织物增强的复合材料吸湿行为具有较大差异;90℃浸泡2160h后,添加碳纤维表面毡的复合材料F2弯曲强度保留率为70.42%,而表面层为方格布的复合材料J的保留率为51.88%;红外光谱(FTIR)研究表明:90℃湿热老化后复合材料基体树脂发生了水解断裂;扫描电镜(SEM)和动态热机械分析(DMA)研究发现:老化后复合材料中纤维/基体界面发生脱粘破坏,界面结合强度降低,试样的Tg和储能模量减小。

Hydrothermal Ageing of Different Fiber Fabrics/Vinylester Composites

In order to investigate the effects of hydrothermal ageing on properties of different fiber fabrics/750 HOI vinylester composites,three kinds of laminated structure composites were prepared and immersed under 60℃ and 90℃ deionized water.Hydrothermal ageing mechanisms of specimens were analyzed through moisture content,flexural property,microstructure and dynamic thermal mechanical property.The results show that moisture absorption behaviors of composites with different fiber fabrics are quite different.After 2160h aged at 90℃,the flexural strength retention rate of composite F2 with carbon fiber surface mat is 70.42％,and composite J with woven roving at the surface is just 51.88％.Fourier transform infrared spectroscopy shows that the matrix resin is hydrolyzed after ageing at 90℃.Scanning electron microscope and dynamic mechanical analysis find that Tg and storage modulus of composites decrease because of the interfacial debonding damage between fiber and matrix.