论文部分内容阅读
利用十二烷基改性海藻酸钠(Na Alg-Dode)在Ti O2纳米颗粒表面上的吸附,得到了稳定的纳米Ti O2颗粒悬浮液。采用傅里叶变换红外光谱仪(FTIR)、动态光散射仪(DLS)及流变仪对颗粒粒径、表面电位及其悬浮体系的流变性进行了测定,研究了不同p H下Na Alg-Dode对纳米Ti O2颗粒在水溶液中聚集行为和流变性的影响。结果表明,加入Na Alg-Dode后,在p H=4~8内均有利于悬浮体系稳定,p H=6.3(等电点)处Ti O2颗粒的平均粒径由2.5μm降低至500 nm左右,颗粒表面Zeta电位由0降低至-40 m V左右。同时随着Na Alg-Dode的加入,Ti O2悬浮体系的剪切应力逐渐增大,表明颗粒间的相互作用增强。由此推知,Na Alg-Dode提高纳米Ti O2颗粒悬浮体系的稳定机制:Na Alg-Dode分子在不同p H下能够通过静电作用、氢键作用及疏水作用等吸附在Ti O2颗粒上,改变颗粒表面电性及空间位阻,从而降低颗粒的团聚。
The adsorption of NaAlg-Dode on the surface of Ti02 nanoparticles was used to obtain a stable suspension of nano-TiO2 particles. The particle size, surface potential and the rheological properties of the suspensions were characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and rheometer. The effects of Na Alg-Dode Effect of Nano Ti O2 Particles Aggregation Behavior and Rheology on Aqueous Solution. The results show that the addition of Na Alg-Dode can stabilize the suspension at p H = 4 ~ 8, and the average particle diameter of Ti O 2 at p H = 6.3 (isoelectric point) is reduced from 2.5 μm to about 500 nm , The Zeta potential of particles decreases from 0 to about -40 mV. At the same time, with the addition of Na Alg-Dode, the shear stress of the Ti O2 suspension gradually increases, indicating that the interaction between the particles is enhanced. It can be deduced that Na Alg-Dode can improve the stability mechanism of nano-Ti O2 particle suspension system: Na Alg-Dode molecules can adsorb on Ti O2 particles through electrostatic interaction, hydrogen bonding and hydrophobic interaction under different p H, Surface electrical and steric hindrance, thereby reducing the particle agglomeration.