端环氧基二氧化硅/环氧树脂/双马来酰亚胺树脂固化反应动力学及性能

Curing Reaction Kinetics and Properties of Epoxy Terminated Silicon Oxide/Epoxy Resin/Bismaleimides

为赋予双马来酰亚胺树脂(BMI)更高的耐热性能和力学性能,并优化其固化工艺,以正硅酸乙酯(TEOS)为前驱体、以末端含有环氧基的(3-环氧乙基甲氧基丙基)三甲氧基硅烷(KH-560)作硅烷偶联剂,采用溶胶凝胶法制备了端环氧基的纳米二氧化硅(E-SiO_(2));以其作为纳米填料,以环氧树脂(EP)作为有机改性体系,共同加入到BMI中进行共聚,以期制备出一种综合性能优异的新型E-SiO_(2)/EP/BMI树脂材料,并详细研究了E-SiO_(2)和EP添加对BMI树脂固化反应动力学的影响。结果表明,相比纯BMI树脂而言,当加入质量分数4.0%的E-SiO_(2)、10.0%的EP时,E-SiO_(2)/EP/BMI树脂体系的凝胶时间从19 min缩短至4 min,但表观活化能变化不大;其弯曲强度从125.53 MPa提高到182.14 MPa,提高了32.3%,且在500℃之前具有更为良好的耐热性能。

To endow the bismaleimide(BMI)resins with higher heat resistance and mechanical properties,the silicon dioxide with terminal epoxy groups(E-SiO_(2))was prepared via sol-gel process using ethyl orthosilicate(TEOS)and 3-epoxide methoxypropyltrimethoxysilane(KH-560)with terminal epoxy groups as precursor and silane coupling agent,respectively,and the curing process of BMI was also optimized.E-SiO_(2)/EP/BMI composites with excellent comprehensive performance were fabricated using E-SiO_(2) as nano-filler and epoxy resin(EP)as organic moification system by the copolymerization of BMI.It is found that the curing reaction kinetics of BMI resin are affected by the addition of E-SiO_(2) and EP.The results show that,compared with the pure BMI resin,the gel time of the E-SiO_(2)/EP/BMI resin system is shortened from 19 min to 4 min with the addition of 4.0%E-SiO_(2) and 10.0%EP,but the apparent activation energy changes little.The bending strength of the material is increased from 125.53 MPa to 182.14 MPa,increased by 32.3%,while it also exhibits a better heat resistance before 500℃.