Characterization of Anionic Reverse Micelles Formulated on Biobased Solvents as Replacing Conventional Nonpolar Organic Solvents

OYARZUN, MAURICIO; OLIVA, GUILLERMO; FALCONE, R. DARIO; PAVEZ, PAULINA

ACS Sustainable Chemistry & Engineering

ACS

Año: 2020 vol. 8 p. 5478 - 5484

2168-0485

Two reverse micelles (RMs) employing 1,4-bis-2-ethylhexylsulfosuccinate (AOT) and two biobased solvents, pcymene (p-cym) or limonene (lim), have been formulated with theaim to obtain systems more environmentally friendly. Both RMswere studied by using different techniques such as dynamic lightscattering (DLS) and 1H NMR. Additionally, spectroscopytechniques were used to obtain information such as critical micellarconcentration and aggregation number of the system investigated.Our results show that both biobased solvents can be used togenerate AOT RMs. Interestingly, even the maximum amount ofwater dispersed are similar for both RMs, and the sizes of thesystems are not identical, being that the RMs are formulated in limlarger than in p-cym. Both the biobased solvent and RMs show interaction of the entrapped water and the interface; however, thisinteraction is different depending on the solvent employed to prepare the RMs. Thus, the interaction water−surfactant at theinterface is weaker in p-cym/AOT than in lim/AOT RMs. We think that the different penetration of the external solvent to theinterfacial region is the main reason for the facts observed. In this sense, the polarity of these biobased solvents could explain why thepenetration of both biobased solvents is different, making the p-cym/AOT RMs less interactive and, therefore, with smaller dropletssizes values. In summary, the different capacities of these biobased solvents to penetrate into the AOT interface allow us to obtain anew interface with peculiar characteristics and therefore with diverse applications.