2—甲苯缩水甘油醚协同提升环氧复合物韧性及刚性研究

Synergistic Enhancement of Toughness and Rigidity of Epoxy Composites by 2—Toluene Glycidyl Ether

电气及电子设备集成度的不断提高,对环氧复合物的热学与力学综合性能提出了更高需求。环氧复合物的耐热性能、刚性与韧性三者之间存在“跷跷板”现象,难以协同提升。该文提出将六氢邻苯二甲酸酐/四氢邻苯二甲酸酐/邻苯二甲酸酐3种固化剂复配提升环氧复合物热学性能,并采用2—甲苯缩水甘油醚协同提升环氧复合物韧性及刚性的方法。研究表明:固化剂复配的方法将环氧复合物的玻璃化转变温度Tg及热分解温度T5%分别提升了17.93%、7.72%;2—甲苯缩水甘油醚改性使得环氧复合物冲击强度和弯曲强度分别提升了123.03%、61.71%。采用分子动力学模拟,从分子角度揭示了2—甲苯缩水甘油醚提升环氧固化物性能的机理,其刚性苯环基团增强了环氧体系分子结构稳定性,柔性—C—O—C—链段改善了交联体系柔韧性。该研究提出一种不降低环氧复合物热学性能,并协同提升其韧性与刚性的可行方法,可为具备高综合热学与力学性能环氧复合物配方的设计提供新思路。

The continuous improvement of the integration of electrical and electronic equipment has put forward higher demands on the comprehensive thermodynamic performance of epoxy composites.“Seesaw”phenomenon exists between heat resistance,rigidity and toughness of epoxy composites,and it is difficult to improve synergistically.In this study,the three curing agents of hexahydrophthalic anhydride/tetrahydrophthalic anhydride/phthalic anhydride are compounded to improve the thermalperformance of epoxy composites.And 2—toluene glycidyl ether is used to synergistically improve the toughness and rigidity of epoxy composites.The study shows that the method of curing agent compounding increases the Tg and T5%of epoxy composites by 17.93%and 7.72%,respectively;the 2—tolyl glycidyl ether modification results in the 123.03%and 61.71%increase in impact strength and flexural strength of the epoxy composites,respectively.Molecular dynamics simulations are used to reveal the mechanism of 2—toluene glycidyl ether from a molecular perspective.Its rigid benzene ring group enhances the stability of the molecular structure of the epoxy system,and the flexible—C—O—C—chain segment improves the flexibility of the cross-linked system.A possible method to enhance the toughness and rigidity of epoxy composites without degrading their thermal performance is proposed in this study,which provides a new idea for the design of epoxy composites formulations with high integrated thermomechanical performance.