摘要
用化学共沉淀法,以不同浓度的葡聚糖40000和20000水溶液作为分散剂,制备纳米铁氧体磁流体。铁氧体粒子的平均直径为15 nm左右,其分散主要依靠空间位阻作用维持。葡聚糖磁流体中铁氧体粒子与葡聚糖以氢键、范德华力结合,葡聚糖包覆量约为8%。随葡聚糖相对分子质量和浓度的升高,磁流体(2.45%)的稳定性上升,用50%葡聚糖40000水溶液制备的磁流体,在室温静置72 h以上,没有分层现象。
Water-based magnetic fluids were prepared by co-precipitation method using dextran 40000 and 20000 solutions of different concentrations as coating agent. The average size of ferrite particles was about 15 nm. The dispersal of particles was obtained due to steric hindrance. Dextran was coated on ferrite particles through hydrogen bond and van der Waals force, and the proportion of coated dextran was about 8 %. The stability of fluids （2.45 % ） was increased with increasing molecular weight and concentration of dextran. As for the fluid coated with 50% dextran 40000, no stratification appeared after placing at room temperature more than 72 h.
出处
《化学世界》
CAS
CSCD
北大核心
2006年第4期193-195,214,共4页
Chemical World
基金
863(2002AA302210)
上海市纳米专项(0249nm071)资助项目
关键词
磁流体
葡聚糖
制备
表征
magnetic fluid
dextran
preparation
property
