Fluorad surfactants, surface tension

Carboxylates with a fluorinated alkyl chain are marketed by the 3M/Industrial Chemical Products Company under the trade name Fluorad surfactants. They also include other functional derivatives of fluorinated and perfluorinated alkyl chains. Replacement of hydrogens on the hydrophobe by fluorine atoms leads to surfactant molecules of unusually low surface tension. This property imparts excellent leveling effectiveness. 

Table 8.1 Surface Tension of Fluorad Fluorinated Surfactants...

The structures and surface tensions of some Fluorad fluorinated surfactants, produced by electrochemical fluorination, are shown in Table 8.1. 3M has discontinued the production of Flourad fluorinated surfactants based on perfluo-rooctanesulfonic and perfluorooctanesulfonic acid (see Chapter 10). The structures and surface tensions of Zonyl fluorinated surfactants, produced by telomer-ization. are shown in Table 4.4. 

Fluorinated surfactants can reduce the surface tension of water and organic solvents and aid wetting of low-energy plastic surfaces. For example, a nonionic fluorinated surfactant, Fluorad FC-740, can lower the surface tension of some low-polarity solvents to 20-24 mN/m and facilitate wetting of plastic surfaces which might be contaminated with silicones, oil, or grease [8]. 

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