水基NiFe_2O_4磁流体在无磁场时的沉降稳定性  

Sedimentation stability of water-based NiFe_2O_4 ferrofluid in the absence of magnetic field

作　　者：胡臻尚 吴张永[1] 莫子勇[1] 蔡晓明[1] 魏镜弢[1] HU Zhenshang;WU Zhangyong;MO Ziyong;CAI Xiaoming;WEI Jingtao(Faculty of Mechanical and Electrical Engineering,Kunming University of Science and Technology,Kunming 650500,Yunnan,China)

机构地区：[1]昆明理工大学机电工程学院,云南昆明650500

出　　处：《化工进展》2017年第9期3414-3421,共8页Chemical Industry and Engineering Progress

基　　金：云南省教育厅科学研究基金(2015Y080);国家自然科学基金(51165012)项目

摘　　要：为研究水基NiFe_2O_4磁流体在不施加磁场时沉降稳定性的影响因素,先采用两步法制备该磁流体样品。其中,纳米粒子为纳米NiFe_2O_4粉体,载液为RO反渗透膜处理水,分散剂包括十二烷基苯磺酸钠、十二烷基硫酸钠、油酸钠、聚乙二醇、十六烷基三甲基溴化铵、油酸和硬脂酸等。在重力场下,研究分散剂种类、质量分数和纳米粒子质量分数对磁流体沉降稳定性的影响,并测量部分磁流体样品的零场黏度,以得到使该磁流体稳定性和流动性较好的制备方法。然后参考以上方法,制备以CoFe_2O_4和Fe_3O_4为纳米粒子的磁流体。并通过与NiFe_2O_4磁流体进行对比,研究水基NiFe_2O_4磁流体在重力场下的热稳定性。实验表明,当分散剂分别为油酸、十二烷基苯磺酸钠和十二烷基硫酸钠,其质量分数分别为4.0%~4.6%、3.4%~3.7%和1.5%~1.7%,且NiFe_2O_4纳米粒子质量分数为1.9%时,这种磁流体的沉降稳定性和流动性能达到较好效果,并且水基NiFe_2O_4磁流体相比其他磁流体具有良好的热稳定性。To study factors that affect sedimentation stability of water-based NiFe2O4ferrofluid in the absence of magnetic field,the ferrofluid samples,firstly,were prepared by two-step method.Among the materials utilized to prepare the fluids,the nanoparticles and carrier liquid were nano NiFe2O4powders and RO reverse osmosis membrane-treated water,respectively and the dispersant agents used include sodium dodecyl benzene sulfonate,sodium lauryl sulfate,sodium oleate,polyethylene glycol,cetrimonium bromide,oleic acid and stearic acid,etc.In gravitational field,the effects of types of dispersant agents,mass fraction of dispersant agent,and the nanoparticles'mass fraction on the stability were explored.Meanwhile,viscosities of some samples were measured to obtain better preparation method which can improve the stability and fluidity of the fluids.Afterwards,using the same method,we prepared two other ferrofluids,with nanoparticles of CoFe2O4and Fe3O4respectively.The NiFe2O4ferrofluid's thermostability in gravitational field was also studied by comparing that of it with its counterparts.The experiments showed that sedimentation stability and fluidity of the fluid could be better when dispersant agents were oleic acid,sodium dodecyl benzene sulfonate and sodium lauryl sulfate whose mass fractions were4.0%-4.6%,3.4%-3.7%and1.5%-1.7%,respectively,and the mass fraction of NiFe2O4nanoparticles is1.9%.Moreover,the fluid is better thermostability compared with other ferrofluids.

关 键 词：NiFe2O4磁流体 重力场 分散剂 纳米粒子 稳定性 沉降 黏度 

分 类 号：TB34[一般工业技术—材料科学与工程]