CTAB在纳米CaCO3表面吸附引起的界面性质变化

利用十六烷基三甲基溴化铵(CTAB)对纳米CaCO3进行表面改性.采用FTIR、XRD、TG-DTG等分析技术对改性前后的纳米CaCO3进行表征,并通过Zeta电位、Brookfield黏度、吸油值、比表面积等实验对纳米CaCO3的表面改性效果进行评价.分析结果表明,CTAB在纳米CaCO3的表面形成化学吸附,经2.0%CTAB表面改性后,纳米CaCO3的界面性质发生了较大变化——纳米CaCO3的Zeta电位由负电性转向正电性,Brookfield黏度大大降低,吸油值由96.8 g降至53.1 g,比表面积从20.1m2/g增大到26.0m2/g.

Change of Interface Properties Caused by CTAB Adsorption on Surface of Nano-Sized Calcium Carbonate

In this paper,cetyl trimethyl ammonium bromide(CTAB) was used to perform the surface modification of nano-sized calcium carbonate.Then,FT-IR,XRD and TGDTG were adopted to characterize the samples before and after the modification.Moreover,the Zeta potential,Brookfield viscosity,oil-absorbed value and specific surface area of the samples were measured to evaluate the modification effect.The results indicate that the modification by CTAB may result in a chemical adsorption on the surface of nano-sized calcium carbonate,and that the modification with 2.0% of CTAB may cause great changes of the interface characteristics.Concretely,the Zeta potential changes form negative to positive,the Brookfield viscosity greatly decreases,the oil-absorbed value decreases from 96.8 g to 53.1 g,and the specific surface area increases from 20.1 m2/g to 26.0 m2/g.