硅含量对气相SiO2/环氧树脂复合材料热稳定性的影响

Effect of Fumed Silica Filler Content on Thermal Stability of Silica/epoxy Resin Composites

采用一定含量的气相SiO_2改性2-氨基苯并噻唑(2-ABZ)固化的4,5-环氧环己烷-1,2-二甲酸二缩水甘油酯环氧树脂(TDE-85),制备一种气相SiO_2/环氧树脂复合材料(SiO_2-EC),通过热重分析(TGA)研究SiO_2-EC的热稳定性能.基于TGA曲线,通过运用扣除SiO_2质量的校正方法与没有扣除SiO_2质量的未校正方法,分别得到校正与未校正的初始分解温度(tIDT),最高质量损失速率温度(tmax)和积分过程分解温度(tIPDT),探究气相SiO_2对复合材料热性能的影响.结果表明:SiO_2-EC校正前后的TGA数据均高于纯环氧树脂,气相SiO_2的加入提高了环氧树脂的热稳定性能,随着气相SiO_2含量的增加,气相SiO_2提高环氧树脂热稳定性的效果呈先增加后降低的趋势,当气相SiO_2含量为6%时增强效果最好,其在复合材料中分散均匀,热稳定性良好,tIDT、tmax和tIPDT分别为291,370,490℃,600℃时的质量保留率为13.52%,比纯环氧树脂提高了5.84%,这是因为气相SiO_2与环氧树脂基体发生了物理交联和化学键合,从而提高了树脂的热稳定性能.

Composites（ SiO2-EC） of fumed silica modified 4,5-epoxycyclohexane 1,2-dicarboxylic acid dilycidyl epoxy resin（ TDE-85） were cured by 2-benzothiazole（ 2-ABZ） and their thermal stabilities were studied by TGA. Initial decomposition temperature（ tIDT）,temperature of maximum rate of weight loss（ tmax） and integration process decomposition temperature（ tIPDT） were found through corrected method of deducting fumed silica weight and uncorrected method of not deducting fumed silica weight to study the thermal stabilities of SiO2-EC. The results showed that the three temperatures of corrected and uncorrected were higher than that of pure epoxy resin,which suggested that fumed silica improved the thermal stability of the epoxy resin. With the increased of fumed silica,tIDTof SiO2-EC appeared increased firstly,and then decreased. When the fumed silica content was 6%,SiO2/6-EC exhibited excellent thermal stability because the fumed silica distributed uniformly and occured physical cross linking and chemical bonding in the epoxy matrix. tIDT,tmax and tIPDTof SiO2/6-EC were 291 ℃,370 ℃ and 490 ℃ respectively,the weight retention was13. 52% at 600 ℃,which was higher than that of pure epoxy resin.