Phase behavior and aggregation property of polyglyceryl-modified silicone surfactant in [EMIM][NTf2]

摘要

Room temperature ionic liquid (IL) 1-ethy1-3-methylimidazoliumBis(trifluoromethylsulfonyl) imide ([EMIM][PITf2]) and Polyglyceryl-modified silicone surfactant (KF-61) binary system and KF-61/[EMIM][NTf2]/silicone oil ternary system were investigated, and the surface tension, dynamic light scattering (DLS), Cryo-transmission electron microscopy (cryo-TEM) and LIV-vis spectra methods and measurements were carried out to characterize the surface activity, phase behavior and aggregation properties. The results revealed that KF-61 can reduce the surface tension remarkably to 23.4 mN.m(-1) in [EMIM][NTf2] and form the micelles with 5 to 80 nm diameter size at different concentrations. By introducing silicone oil, nonaqueous reverse microemulsion consisting of [EMIM][NTf2]/KF-61/silicone oil were formulated for the first time, and the phase diagram was studied using UV-vis absorbance spectra of methyl orange (MO) to verify the characteristics at different compositions of [EMIM][NTf2] in silicone oil (IL/Si) microemulsions. The results indicated that the polarity of the microenvironment increased with successive addition of the [EMIM][NTf2] into the KF-61/silicone oil system and would be constant once the IL pools were formed. The IL pools size in microemulsion grows from 25 to 94 nm and this may find positive factors for potential applications such as microreaction compartmentalization etc. (C) 2016 Elsevier B.V. All rights reserved.