纳米二氧化硅粒子的改性研究

Modification of nano silicon dioxide particles

利用傅立叶红外光谱仪、接触角测试仪和Zeta电位测定仪等仪器分别测试未改性和γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)改性的纳米二氧化硅粒子表面的分子结构、接触角和电荷,分析两者之间的宏观性能和微观分子结构区别,以此判断改性效果;采用TG定量分析纳米二氧化硅(Si O_2)表面偶联剂KH570的接枝率,研究分散液的p H值、偶联剂用量、水用量等工艺条件对接枝率的影响,结果表明:当偶联剂KH570用量在20%二氧化硅质量范围内,随着偶联剂用量增加接枝率不断增大,当超过这个用量后,则由于空间位阻效应导致接枝率变化不明显.

Fourier transform infrared spectrometer,contact angle test and nano particle potential meter were used to analysis the surface structure,contact angle and charge of unmodified nano silica particles and γ-（ methacryloxypropyl） trimethoxy silane（ KH570） modified nano silica particles,macro-properties and micro molecule structure were discussed to judge the surface modification effect; TG was used to analysis the content of KH570 on the surface of nano silicon dioxide（ Si O2）. Effects of the dispersion of p H value,the content of KH570 and water on the graft ratio were discussed. The results showed that： the dispersion of p H value and the content of water had a great effect on the graft ratio. When KH570 was less than 20% silicon dioxide,graft ratio increased with the content of KH570 increasing,when KH570 was more than 20%,graft ratio changed little because of space steric effect.