聚醚砜/氰酸酯/环氧树脂体系固化动力学及韧性研究

Study on Curing Kinetics and Toughness of PES/Cyanate/Epoxy Resin System

采用非等温DSC法分别对氰酸酯/环氧树脂(CE/EP)及聚醚砜/氰酸酯/环氧树脂(PES/CE/EP)体系的固化过程进行了研究。利用Kissinger法计算得到两个体系固化反应的表观活化能Ea、指前因子A、固化反应级数n等动力学参数,建立了固化反应动力学方程,并用T-β外推法确定了固化工艺。通过红外光谱、力学性能测试、扫描电镜等方法研究了PES/CE/EP体系的固化反应机理、浇铸体力学性能及微观形貌。结果表明,PES的加入,降低了CE/EP体系固化反应的完全程度,体系的Ea由61.76降低到60.41KJ/mol,A由8.50×105提升到7.22×105,两个体系的反应级数基本一致。PES/CE/EP体系比较合理的固化工艺为120℃/2h+150℃/1h+180℃/4h+200℃/2h。PES的加入可有效改善CE/EP体系的冲击韧性,当PES含量达到15wt%时达到最佳,是CE/EP树脂体系冲击强度的2倍,并且浇铸体断口形貌呈现出明显的颗粒相结构,同时该颗粒相又以连续相的形式分散在树脂体系中,使得浇铸体力学性能最优。

The curing process of cyanate ester/epoxy resin(CE/EP)and polyether sulibne/cyanate ester/epoxy resin(PES/CE/EP)systems was studied by non-isothermal DSC.The kinetic parameters such as apparent activation energy Ea,pre-exponential factor A and curing reaction order n of the two systems were calculated by Kissinger method,and the curing reaction kinetic equation was established,and the curing process was determined by T-βextrapolation method.The curing reaction mechanism,casting mechanical properties and micro-morphology of PES/CE/EP system were studied by means of infrared spectrum,mechanical properties test and scanning electron microscope.The results showed that the addition of PES reduced the complete degree of the curing reaction of CE/EP system,and the Ea of the system decreased from 61.76 to 60.41 KJ/mol,and A increased from 8.50x105 to 7.22x105,and the reaction order of the two systems was basically the same.The reasonable curing process of PES/CE/EP system is 120℃/2h+150℃/1 h+180℃/4h+200℃/2h.The addition of PES can effectively improve the impact toughness of CE/EP system,which can be reached when the PES content reaches 15wt%.