Synthesis and Characterization of Some Nonionic Bolaamphiphiles

Abstract

A series of nonionic bolaamphiphiles were synthesized from the reaction of fluoroalkylene (dimercaptoacetates) with maleate crown ethers. Surface activity of the new surfactants was evaluated on the basis of surface tension measurements. The new fluorinated bolamphiphiles exhibit a remarkable lowering of surface tension in comparison with nonfluorinated analogues.

Synthesis and Determination of Critical Micelle Concentration of Betainthioates Surfactants

“…Nevertheless, when compared to other surfactants, compounds 3 exhibit higher and comparable CMC values toward nonionic (Khalfallah et al, 2010; Khalfallah et al, 2014) and cationic (Victor et al, 2013) surfactants respectively.…”

“…The synthetic procedure for the preparation of betainthioates series carrying a single hydrocarbon chain ( 3a‐f ) are depicted in Scheme 1. The starting compounds, alkyl sulfanylacetate 1a‐c and alkyl‐α,ω‐diyl bis(sulfanylacetate) 1d‐f were prepared by esterification reaction of mercapto acetic acid with respectively alcohol and diol (Khalfallah et al, 2014). These compounds were reacted with excess of bromoacetyl bromide in triethylamine (Narasimhan et al, 2007) to afford respectively alkyl [(bromoacetyl)sulfanyl]actate 2a‐c and alkyl‐α,ω‐diyl bis{[(bromoacetyl)sulfanyl]acetate} 2d‐f .…”

“…On the other hand, the CMC values of bolaphiles 3d‐f are higher than those monotailed analogues 3a‐c . This could be explained by the better solubility of bola‐types (Khalfallah et al, 2014).…”

Structure and Applications of Surfactants

“…These surfactants (Figure 17) may be inefficient in the formation of aggregates because of their low hydrophilicity. This problem is solved by the addition of a cap anion [97] or by the introduction of an oligooxyethylene group between the hydrophobic part and the ring of crown ethers [98][99][100] to reinforce the hydrophilicity.…”