用低支化聚酯液晶/POSS共混改性环氧树脂的研究

Study on the blend modification of epoxy resin by lower-branched liquid crystalline polyester/POSS

以对羟基苯甲酸、对苯二甲酰氯和偏苯三酸酐(TMA)为原料,合成了低支化聚酯液晶聚合物(LLCP),并将其与γ-氨基六面体倍半硅氧烷(POSS)协同改性环氧树脂体系。研究结果表明,LLCP/POSS能对环氧树脂复合材料起到很好的增韧作用,改性后的环氧树脂复合材料冲击性能是纯环氧树脂的2.1倍。利用扫描电镜(SEM)观察复合材料断裂面形貌,探讨其增韧机理。热重分析(TG)表明:改性后材料的起始分解温度和最大分解速率温度分别比纯环氧树脂高出20℃和13℃,材料热稳定性提高。

A new kind of lower-branched liquid crystalline polyester(LLCP) containing polyester mesogenic units was synthesized by p-hydroxybenzoic acid,terephthalyl chloride and trimellitic anhydride(TMA),then was used as collaborative modifier for the epoxy resin(E-51) with γ-azyl polyhedral oligomeric silsesquioxane(POSS).The experimental results showed that the LLCP / POSS could act as an effective toughening modifier for the epoxy resin.The impact strength of the composites modified with LLCP and POSS was 2.1 times higher than that of the unmodified system,and discussed the toughening mechanism by SEM.The temperature of starting decomposition and maximum decomposition rate improved about 20℃ and 13℃,respectively.