纳米填料对含长链取代基液晶环氧树脂固化动力学及热性能的影响

Effect of nano-fillers on curing kinetics and thermal property of liquid crystalline epoxy resins with long chain substituents

制备了几种不同纳米粒子(SiO2、TiO2、有机化黏土10A、有机化黏土30B)填充的液晶环氧树脂EP-6-DDM复合材料,并用差示热分析(DSC)、偏光显微镜(POM)、X射线衍射(XRD)和热失重分析(TGA)等方法研究了纳米填料/EP-6-DDM复合材料体系的固化反应过程及其相结构变化和热性能。结果表明,四种纳米填料对于EP-6-DDM体系均有催化作用,其中SiO2的催化能力最强,有机化黏土30B的催化能力最弱。当黏土的质量分数为1%时,形成了剥离型纳米复合材料,大于3%时则剥离型和插层型共存。纳米填料的加入并未改变EP-6-DDM的液晶相织构,但是会破坏向列相液晶纹影织构的形成和完整性。热分析结果表明,纳米填料的加入使体系的热稳定性略有降低。

A series of nano{illers/iiquid crystalline epoxy composites with different nano-filiers were prepared. The curing reaction and phase behavior of 2,5 - his [-4- （2,3- epoxypropoxy） - oxy] benzoic acid hexanol ester （EP- 6） - 4, 4＇-diaminodiphenyl methane （DDM） system were studied by non-isothermal DSC, POM and XRD. The thermal property of the nano- fillers/EP- 6 - DDM composites was characterized by TGA. It was found that in all the four nano- fillers catalyzed the curing of EP- 6 - DDM system. SiO2 has the highest catalytic reactivity and organoclay cloisite 30B has the lowest. The XRD data indicated that only exfoliated nanocomposites formed when the mass fraction of 30B is below 1%, while both exfoliated and intercalated nanocomposites formed when the content of 30B is above 3%. Polarizing optical microscope observation showed that the nano-fillers did not change the nematic structure of resin matrix, but retarded the appearance of nematic texture. Thermogravimetric analysis indicated that the thermal stability of cured nano-fillers/EP-6 -DDM decreased slightly.