Resolving the puzzle of ferrofluid dispersants

被引：149

作者：

Tadmor, R ^{[1
]}

Rosensweig, RE ^{[1
]}

Frey, J ^{[1
]}

Klein, J ^{[1
]}

机构：

[1] Weizmann Inst Sci, Dept Mat & Interfaces, IL-76100 Rehovot, Israel

来源：

LANGMUIR | 2000年 / 16卷 / 24期

关键词：

D O I：

10.1021/la0009137

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Oleic acid and stearic acid are similar surfactants which, however, lead respectively to stability and to precipitation of ferrofluid suspensions: to understand this, the forces between layers of oleic-like surfactants and between layers of stearic-like surfactants across a hexadecane (HD) medium were measured using a surface force balance (SFB). Separate measurements reveal that only the oleic layers are solvated by HD, while the SFB results reveal that for both surfactants a marked net attraction is present between the surfaces. Simple considerations based on these observations explain why, despite this attraction, ferrofluid dispersions are stabilized by oleic but not by stearic surfactants.

引用

页码：9117 / 9120

页数：4

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