Fluorinated surfactants properties

Fluorinated Surfactants Synthesis Properties Applications, Erik Kissa... 

Chemistry of Organic Fluorine Compounds II Table 7. Properties of Fluorinated Surfactants... 

E Kissa, Fluorinated surfactants synthesis, properties, applications (New York Marcel Dekker, 1993). 

E. Kissa, In M.J. Schick and F.M. Fowkes (Eds.), Fluorinated surfactants synthesis, properties, applications, Surfactant Science Series, Vol. 50, Marcel Dekker, New York, USA, 1994. 

Kissa, E. (1994) Fluorinated Surfactants-Synthesis, Properties and Applications. Dekker, New York. 

Kissa, E. Fluorinated Surfactants, Synthesis, Properties, Applications. Marcel Dekker, New York, 2001. 

Fluorinated surfactants (or fluorosurfactants, i.e., surfactants with hydrophobic tails comprising a fluorocarbon moiety) provide an alternative means of achieving extremely stable PFC emulsions, as they can provide very low PFC/water interfacial tensions [cr , another factor in Eq. (2)]. d s yet, this option has not been developed, in part because of the added cost involved in the evaluation for approval of a novel active excipient. A further means of effectively increasing the stability of EYP-based PFC emulsion consists of supplementing standard phospholipids with mixed fluorocarbon-hydrocarbon diblock compounds, such as 14 or 15. Such diblocks, which have fluorophilic-lipophilic amphiphilic properties, are expected to improve the adhesion of the phospholipid film onto the PFC droplet. 

Fluorinated surfactants or graft polymers are typically necessary in C02 applications [48, 49]. Research into the self-assembly of these surfactants and polymers in C02 have focused on dilute systems where only reverse water-in-C02 micelles are expected [39, 50-52, 53]. Regions of the phase diagrams where C02-in-water micelles, bicontinuous microemulsions or liquid crystalline phases are formed remain to be investigated in detail. There is only one system known so far where all these phases have been observed. We will come back to this at the end of Section 7.4. The properties of reverse micelles in C02... 

In this chapter, we focus in two kinds of surfactants that so far have not been common as structure-directing agents in the synthesis of mesoporous silica, namely, silicone and fluorinated surfactants, having a hydrophobic chain different from that of conventional hydrocarbon surfactants, which imparts peculiar properties to the systems. 

Fluorinated surfactants can be very intereshng for the preparation of mesoporous materials, due to their good self-aggregation properties, allowing a more precise control of the mesostructure and properties of materials. In this context, the use of fluorocarbon surfactants allows the formahon of ordered mesoporous materials with a long-range organizahon [52, 53],... 

Nowadays, partially or fuUy fluorinated surfactants are available with a variety of chemical structure and chain lengths. Therefore hydrophilic-lipophilic properties can be controlled and these new surfactant molecules may provide a rich phase behavior, which could be used to obtain well-organized mesoporous materials. 

Surfactants with hydrophobic chains different from conventional hydrocarbon alkyl chains possess interesting properties as structure-directing agents in self-assembly processes. Both silicone and fluorinated chains are less soluble in many organic solvents than their hydrocarbon counterparts. Moreover, sihcone and fluorinated surfactants reduce the surface tension of water more effectively than... 

In this context, silicone and fluorinated surfactants, which can impart peculiar properties to mesoporous materials, constitutes a research field that may be exploited to obtain new nanostructured materials for novel applications and many future developments may still arise in this field. The literature on the use of nonhydrocarbon surfactants for the preparation of mesostructured materials remains relatively scarce and many aspects are still unexplored. 

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