Synthesis of phosphate-type fluorocarbon–hydrocarbon hybrid surfactants and their adsorption onto calcium hydroxyapatite

Abstract

Five novel phosphate-type hybrid surfactants, C m F 2m+1 C 6 H 4 CH[OPO 2 (OC 6 H 5 )Na]C n H 2n+1 (FmPHnPPhNa: m = 4, 6, 8; n = 3, 5; C 6 H 4 = p-phenylene, C 6 H 5 = phenyl), have been synthesized. When compared with sulfate-type hybrid surfactants, C m F 2m+1 C 6 H 4 CH(O-SO 3 Na)C n H 2n+1 (C 6 H 4 = p-phenylene), the new hybrid surfactants are found to have comparable abilities to lower surface tension of water. The critical micelle concentrations of FmPHnPPhNa follow Klevens rule and their occupied areas per molecule increase with increasing m and n. Calcium hydroxyapatite (CaHAp) pellets modified with FmPH3PPhNa gives high hydrophobic and lipophobic surfaces. The hybrid surfactants are expected as new dental reagents for oral hygiene. #

Synthesis and Solution Properties of Sulfate-Type Hybrid Surfactants with an Ethylene Spacer

“…FmPHnS are expected to be a good emulsifier for making aqueous fluorocarbon paints because they are able to emulsify fluorocarbon/water/hydrocarbon systems (6). The present authors have also reported that the synthesized hybrid surfactants form long-life micelles detected by NMR (7) and abnormally highly viscous solutions at about 10 wt% and 36 (8)(9)(10)(11)(12), and have a human tooth reformability for the prevention of its decay (13). These properties are characteristic of the hybrid surfactants and cannot be developed by mixed systems of fluorocarbon and hydrocarbon surfactants.…”

“…S N (13) Here, N is the aggregation number and S and S N denote respectively monomer and micelle. The equilibrium constant K is given by Eq.…”

Micelle Formation of Phosphate-Type Hybrid Surfactants in Aqueous Solution

“…The synthesis of phosphate-type hybrid surfactants has been described elsewhere (10). They are denoted as FmPHnPPhNa in ref.…”

“…A series of novel phosphate-type hybrid surfactants ( Fig. 1(a)) have been synthesized quite recently (10). This type of surfactants is expected to be useful in the field of dentistry, because they would adsorb strongly on teeth due to the phenyl phosphate group and would keep the teeth clean owing to their hydrophobic and lipophobic nature.…”

“…This type of surfactants is expected to be useful in the field of dentistry, because they would adsorb strongly on teeth due to the phenyl phosphate group and would keep the teeth clean owing to their hydrophobic and lipophobic nature. Actually, it was demonstrated that the surface of calcium hydroxyapatite pellets modified with FmPHnPPhNa exhibit high hydro-and lipophobicity (10). Aside from the dental application, the solution property itself is also an interesting research subject for this series of surfactants.…”