摘要：采用3种硅烷偶联剂双-[γ-(三乙氧基硅)丙基]四硫化物(Si69)、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)、乙基三甲氧基硅烷(11-100)对沉淀法白炭黑粉体进行有机湿法改性。借助傅里叶红外光谱、接触角仪、纳米粒度及Zeta电位仪、扫描电镜等检测手段对白炭黑改性前后的结构及性能进行表征,研究考察3种不同偶联剂对沉淀法白炭黑的疏水性及分散性的影响。结果表明:3种不同硅烷偶联剂都已成功接枝到白炭黑表面,其中Si69改性的白炭黑剩余羟基数与未改性白炭黑表面羟基数的比值最小,为34.23%;经偶联剂改性后的白炭黑,团聚现象减弱,粒径分布变窄,分散性得到改善,疏水性大小依次为Si69-SiO₂>KH570-SiO₂>11-100-SiO₂;综合对比3种偶联剂的改性效果,Si69的改性效果最好。

关键词：白炭黑；硅烷偶联剂；表面改性；疏水性；分散性

Abstract：Three different silane coupling agents bis [γ-(triethoxysilyl)propyl]tetrasulfide(Si69), γ-methacryloxypropyl trimethoxy silane(KH570), ethyltrimethoxysilane(11-100)were used to modify the precipitated silica powder by organic wet process. Then, the structure and property of silica of before and after modification were characterized by Fourier transform infrared spectroscopic, contact angle instrument, nanoparticle size, Zeta potentiometer, and scanning electron microscopy. The effects of three different coupling agents on hydrophobicity and dispersion of precipitated silica were studied. The results show that three different silane coupling agents are grafted successfully onto the surface of silica, the content of remaining hydroxyl of silica modified by Si69 reaches the minimum 34.23%. After the silica modified by the coupling agents, the reunion phenomenon reduces, the size distribution becomes narrow, the dispersity obtains obvious improvement. The hydrophobicity is in turn Si69-SiO₂>KH570-SiO₂>11-100-SiO₂. Through the comparison of modification effect, the modification effect of Si69 is the best in all products in this test.

Keywords: precipitated silica；coupling agent；surface modification；hydrophobicity；decentrality