JSD-12-0080 Supplementary files

Aggregation behaviorof surface active dialkylimidazolium ionic liquids [C12Cnim]Br (n=1-4)in aqueous solutions

Xuefeng Liu* · Jie Hu · Yijun Huang · Yun Fang

The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China

ESM Figure 1 The ESI-MS spectra of [C12Cnim]Br, (n=2-4) with positive ion mode.

ESM Table 1

The results of elemental analysis for [C12Cnim]NO3, (n=2-4).

[C12C2im]NO3 / [C12C3im]NO3 / [C12C4im]NO3
Found / calculated / Found / calculated / Found / calculated
C / 62.33% / 62.35% / 63.30% / 62.31% / 64.13% / 64.19%
H / 10.32% / 10.16% / 10.38% / 10.33% / 10.56% / 10.49%
O / 14.55% / 14.66% / 14.02% / 14.06% / 13.49% / 13.50%
N / 12.80% / 12.83% / 12.30% / 12.30% / 11.82% / 11.82%

ESM Figure 2 The1H NMR spectra of [C12Cnim]Br, (n=2-4) using CDCl3 as the solvent.

ESM Figure 3 The plot of γversus the drop detachment time t at 25 oC and the concentration of [C12C1im]Br is fixed at 0.063 mmol L-1.

The calculation of the activity (a) of the surfactant solutions

The activity coefficients can be calculated by the Debye-Hückel limiting law:

where γ± is the mean activity coefficient of the 1:1 ionic surfactant, ε is the dielectric constant of water (78.48 at 25 oC) [1], T is the temperature (K), z+ and z- are the ion charge of the surfactant in aqueous solution, and I is the ion strength of the surfactant solution.

Reference

[1] Albright P S, Gosting L J (1946) Dielectric Constants of the Methanol-Water System from 5 to 55°. J. Am. Chem. Soc. 68: 1061-1062

ESM Figure 4Pyrene fluorescence emission spectra in [C12C1im]Br aqueous solution at 25 oC. c([C12C1im]Br) is 0.06 molL-1, c(Py) is 1.0×10-7 molL-1, cQ/(mmolL-1): (a) 0,(b) 0.08,(c) 0.16,(d) 0.24,(e) 0.32, and (f) 0.40.

ESM Figure 5Theplot of ln(I0/I) versuscQ of [C12C1im]Br aqueous solution at 25 oC.The data of fluorescence quenching are from the ESMFigure 4.

Thus,

c=0.06 molL-1, CMC=8.22 mmolL-1,

Nm=59.5