Synthesis and properties of gemini-type hydrocarbon–fluorocarbon hybrid surfactants

Abstract

Gemini-type hybrid surfactants with two fluorocarbon chains connected through a hydrocarbon spacer, F(CF 2) m (CH 2) 2CH(OSO 3Na)(CH 2) n CH(OSO 3Na)(CH 2) 2(CF 2) m F [F m(H n)F mOS, m = 4, 6; n = 5, 6, 7, 8)], were synthesized and their surface chemical properties were examined with the aim to have highly functional and highly water-soluble fluorinated surfactants when compared with the conventional fluorinated surfactants. Comparisons of the surface chemical properties of the synthesized gemini-type hybrid surfactants with those of monounit-type hybrid surfactants, F(CF 2) m (CH 2) 2CH(OSO 3Na)(CH 2) n H [F mEH nOS, m = 4, 6; n = 3, 5)], revealed that gemination causes a remarkable lowering (about 1/100) in cmc value while it produces little changes in Krafft point (below 0 °C) and surface tension at cmc ( γ cmc).