摘要
利用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对提纯海泡石矿物进行表面改性,探索改性前、后海泡石表面性能的变化。利用傅里叶红外光谱(FTIR)、光电子能谱(XPS)、热分析(TG-DTA)、表面张力仪、Zeta电位仪和扫描电镜(SEM)等手段测试改性前、后海泡石表面官能团的存在形式及键合状态的变化。结果表明:KH-570以物理包覆和化学键合两种方式存在于海泡石纳米纤维的表面,其化学接枝率约为38.3%。海泡石表面Si2p的电子结合能减少了0.22 eV,O1s的电子结合能减少了0.78 eV,O原子的化学位移较大,说明接枝反应发生在Si—OH中的O原子上。改性后海泡石粉体的表面自由能由52.63 m J/m^2减小到31.56 m J/m^2,Zeta电位绝对值增大,减轻了海泡石纳米纤维的团聚行为。
The modified sepiolites were prepared by organic surface modification via γ-methacryloxypropyl trimethoxy silane （KH-570） in order to explore the variation trend of surface properties of sepiolite.The existing form and chemical bonding state of surface functional groups of modified sepiolites were studied by infrared spectroscopy （FTIR）, photoelectron spectroscopy （XPS）, thermal analysis （TG-DTA）, the surface tension meter, zeta potential and scanning electron microscopy （SEM）, respectively.The result show that the KH-570 exists on the surface of modified sepiolites by two ways of physically coating and chemically bonding, and the chemical grafting rate is about 38.3%.The binding energy of Si2p and O1s decreases by 0.22 eV and 0.78 eV, respectively.It indicates that the grafting reaction occured in O atoms of Si-OH groups due to the larger chemical shift of O atoms.Finally, the surface free energy decreases from 52.63 mJ/m2 to 31.56 mJ/m2 and the absolute value of zeta potential rapidly increases, which demonstrates that the aggregate behavior of sepiolite nano-fiber can be effectively reduced.
出处
《科学技术与工程》
北大核心
2017年第20期17-22,共6页
Science Technology and Engineering
基金
河北省自然科学基金(E2013202142)资助
关键词
无机非金属材料
海泡石
表面改性
官能团
接枝率
inorganic non-metallic materials
sepiolite
surface modification
functional group
grafting rate
