热致性液晶固化剂增韧环氧树脂的研究

Epoxy Resin Toughened by Thermotropic Liquid Crystal Curing Agent

合成了一种环氧树脂的热致性液晶固化剂 ,利用红外光谱、偏光显微镜 (POM )、差热分析仪 (DSC)、元素分析等手段确认其结构。将此液晶固化剂加入环氧树脂 /二氨基二苯砜 (DDS)固化体系中 ,测试了固化物的力学性能 ,并用热重分析仪 (TG)、DSC测试了固化物的玻璃化转变温度 (Tg)和热失重温度 (Td) ,用偏光显微镜 (POM )对不同配比的环氧树脂 /液晶固化剂体系的固化样品形貌进行观察。结果表明 :加入不到 3 %的液晶固化剂 ,可以使环氧固化物的拉伸强度提高 5 0 % ,冲击强度提高近一倍 ,Tg 和Td 明显提高 ,偏光显微镜照片表明液晶固化剂的加入使固化体系出现了相分离。

A novel thermotropic liquid crystal curing agent was synthesized to modify epoxy resin. The structure and composition of LCC were analyzed by FTIR and Element Analyzer. Liquid crystalline behavior of LCC was characterized by DSC and POM. When LCC was added to epoxy resin/DDS curing system, mechanical and thermal properties of the curing materials were tested. The result showed that LCC enhanced the impact strength of the curing material by 100 %,tensile strength by 50 % while only less than 3 % LCC was incorporated into the curing system. The thermal performance was also improved. POM observation of the LCC-epoxy resin curing system showed that the phase separation occurred with the addition of liquid crystal curing agent.