Performance Characteristics of Fluorinated Surfactants

A unique characteristic of fluorinated surfactants is the chemical stability of the fluorocarbon chain to strong acids, oxidizing agents, and concentrated alkalis. Hence, fluorinated surfactants can be used in media where hydrocarbon-based surfactants would decompose. 

Fluorinated surfactants are useful emulsifiers and dispersants for systems in which either the continuous phase or the disperse phase is a fluorocarbon. Mixtures of fluorinated and hydrocarbon surfactants can be more effective and less expensive than each component alone. 

Note Rf = F(CF2)n- Surfactant concentrations are given in percent active ingredient. Source Ref. 8. 

The foaming properties of fluorinated surfactants vary widely (see Section 4.9). For example, amphoteric surfactants, Zonyl FSK and Zonyl FSC, are outstanding foaming agents. In contrast, the anionic fluorinated surfactant, Zonyl FSP, and the nonionic fluorinated surfactant, Zonyl FSN, are low foaming. In some systems, Zonyl FSP can function as an antifoam agent. 

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. 

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