双酚A型活性酯的环氧固化行为及其性能研究

Study on the curing behavior for epoxy resin of bisphenol A type active ester and its performance

以双酚A型活性酯(H7070)为双环戊二烯环氧树脂(DCPD)和酚醛环氧树脂(638S)的固化剂,采用傅里叶红外光谱(FTIR)对两种环氧体系固化前后的结构进行了表征,发现固化后环氧基伸缩振动峰几乎消失。通过非等温示差扫描量热法研究两种环氧体系的固化行为,分别得到两种体系的表观活化能、反应级数、表观指前因子和动力学方程。对两种体系进行热重分析,发现H7070/DCPD体系有2个热失重峰,H7070/638S体系有1个热失重峰,H7070/DCPD的热稳定性略优于H7070/638S。两种环氧体系的介电指标相近,介电性能良好。试样H7070/DCPD的弯曲强度,冲击强度分别为92 MPa和60kJ/m^2,略优于H7070/638S。

The bisphenol A type active ester(H7070)was used as curing agent for dicyclopentadiene epoxy resin(DCPD)and novolac epoxy resin(638 S). The structures of the two epoxy systems before and after curing were characterized by FTIR,and it was found that the epoxy stretching vibration peak was disappeared almost after curing. The curing behaviors of the two epoxy systems were studied by non-isothermal differential scanning calorimetry,and the apparent activation energy,reaction order,apparent pre-exponential factor and kinetic equation of the two systems were obtained. The thermogravimetric analysis of the two systems showed that the H7070/DCPD system had two thermogravimetric peaks,and the H7070/638 S system had one thermogravimetric peak. The thermal stability of H7070/DCPD was slightly better than that of H7070/638 S.The dielectric properties of the two epoxy systems were similar and the dielectric properties were good. The flexural strength and impact strength of the sample H7070/DCPD were 92 MPa and 60 k J/m^2,respectively and slightly better than those of H7070/638S.