由于氨基酸基的独特性质，我们以甘氨酸作为阴离子，醚基咪唑基团作为阳离子合成了一种新型离子液体1-甲氧乙基-3-甲基咪唑甘氨酸[MOEMIM][Gly]，并经过核磁共振氢谱、核磁共振碳谱和差示扫描量热进行表征。由于离子液体和水之间形成氢键导致传统的方法不能去除水的影响，所以在实验测定中，选用标准加入法在温度范围为298.15–338.15 K,每隔5 K测定离子液体[MOEMIM][Gly]的密度和表面张力。利用密度数据，计算得到离子液体[MOEMIM][Gly]的摩尔体积，并且摩尔体积随着温度的升高而增加，同时得到了热膨胀系数。根据离子液体[MOEMIM][Gly]的摩尔表面Gibbs自由能，改进了传统的E？tv？s经验方程，使得方程具有更明确的物理意义，即截距C0代表摩尔表面焓，它是一个与温度无关的常数，斜率则为摩尔表面熵，这表明改进的E？tv？s方程不仅是一个经验方程，而且还是严格的热力学方程。另外，结合摩尔表面Gibbs自由能和改进的E？tv？s方程，估算了离子液体的[MOEMIM][Gly]的表面张力，并与实验值进行比较，发现两者很好的一致。 Because of the unique acid-base behavior of amino acids, we combined glycine as the anion with an ether group as the cation and prepared a novel ionic liquid (IL), 1-methoxyethyl-3-methylimidazolium glycine [MOEMIM][Gly]. The formation of this IL was confirmed by 1H-NMR, 13C-NMR, differential scanning calorimetry (DSC) and thermogravimetry (TG) analyses. The density, ρ, and surface tension, γ, of the ILs were measured in the temperature range from 298.15 K to 338.15 K at intervals of 5 K using the standard addition method, because the strong hydrogen bonds between the IL [MOEMIM][Gly] and trace amounts of water made it, extremely difficult to remove water by convention methods. The calculated molar volume, Vm, of [MOEMIM][Gly] increased with increasing temperature. The thermal expansion coef？cient, α, was also obtained based on the density values. In terms of the molar surface Gibbs free energy, gs for [MOEMIM][Gly], the traditional E？tv？s equation is improved so that it has physical signi？cance, that is, the intercept C0 represents molar surface enthalpy, h, which is a temperature-independent constant and the slop C1 = ？($\partial $gs/$\partial $T)p is molar surface entropy, s, it shows that modified E？tv？s equation is not only an empirical equation, but also a strict thermodynamic one. In addition, by a combination of gs and the modified E？tv？s equation, the surface tension values of [MOEMIM][Gly] were estimated and compared with the experimental values; both sets of data were in good accordance with each other
References
[1]
1 Beniwal V. ; Kumar A. J. Phys. Chem. B 2017, 121, 11367. doi: 10.1021/acs.jpcb.7b08240
[2]
2 Kuhlmann E. ; Himmler S. ; Giebelhaus H. ; Wasserscheid P. Green Chem. 2007, 9, 233. doi: 10.1039/B611974C
[3]
3 Zhao H. ; Baker G. A. ; Song Z. ; Olubajo O. ; Crittle T. ; Peters D. Green Chem. 2008, 10, 696. doi: 10.1039/B801489B
[4]
4 Zhao H. ; Jones C. L. ; Cowins J. V. Green Chem. 2009, 11, 1128. doi: 10.1039/B905388C
[5]
5 Zhao H. ; Baker G. A. ; Cowins J. V. Biotechnol. Prog. 2010, 26, 127. doi: 10.1002/btpr.331
[6]
6 Galletti P. ; Moretti F. ; Samori C. ; Tagliavini E. Green Chem. 2007, 9, 987. doi: 10.1039/B702031G
[7]
7 Revelli A. L. ; Mutelet F. ; Jaubert J. N. ; Garcia-Martinez M. ; Sprunger L. M. ; AcreeJr W. E. ; Baker G. A. J. Chem. Eng. Data 2010, 55, 2434. doi: 10.1021/je900838a
[8]
8 Mutelet F. ; Revelli A. L. ; Jaubert J. N. ; Sprunger L. M. ; Acree W. E. ; Baker G. A. J. Chem. Eng. Data 2010, 55, 234. doi: 10.1021/je9003178
[9]
28 Wei J. ; Fan B. H. ; Pan Y. ; Xing N. N. ; Men S. Q. ; Tong J. ; Guan W. 2016, 101, 278. doi: 10.1016/j.jct.2016.03.043
[10]
23 Fang D. W. ; Tong J. ; Guan W. ; Wang H. ; Yang J. Z. J. Phys. Chem. B 2010, 114, 13808. doi: 10.1021/jp107452q
[11]
27 Tong J. ; Yang H. X. ; Liu R. J. ; Li C. ; Xia L. X. ; Yang J. Z. J. Phys. Chem. B 2014, 118, 12972d. doi: 10.1021/jp509240w
[12]
9 Yang Z. Z. ; Zhao Y. N. ; He L. N. RSC Adv 2011, 1, 545. doi: 10.1039/C1RA00307K
[13]
10 Ginderen P. V. ; Herrebout W. A. ; van der Veken B. J. J. Phys. Chem. A 2003, 107, 5391. doi: 10.1021/jp034553i
[14]
11 Sasaki K. ; Matsumura S. ; Toshima K. A. Tetrahedron Lett. 2004, 45, 7043. doi: 10.1016/j.tetlet.2004.07.128
[15]
12 Wang L. ; Zhang Y. H. ; Xie C. S. ; Wang Y. G. 2005, 36, 1861. doi: 10.1055/s-2005-871566
[16]
13 Luo C. ; Zhang Y. ; Wang Y. J. Mol. Catal. A: Chem. 2005, 229, 7. doi: 10.1016/j.molcata.2004.10.039
[17]
14 Petrovi? Z. D. ; Markovi? S. ; Petrovi? V. P. ; Simijonovi? D. J. Mol. Model. 2012, 18, 433. doi: 10.1007/s00894-011-1052-1
[18]
15 Monteiro M. J. ; Camilo F. F. ; Ribeiro M. C. C. ; Torresi R. M. J. Phys. Chem. B. 2010, 114, 12488. doi: 10.1021/jp104419k
[19]
16 Smith G. D. ; Borodin O. ; Li L. ; Kim H. ; Liu Q. ; Bara J. E. ; Gin D. L. ; Nobel R. A. Phys. Chem. Chem. Phys. 2008, 10, 6301. doi: 10.1039/B808303G
[20]
17 Fang S. ; Yang L. ; Wang J. ; Li M. ; Tachibana K. ; Kamijima K. Electrochim. Acta 2009, 54, 4269. doi: 10.1016/j.electacta.2009.02.082
[21]
18 Zheng J. C. ; Tong X. ; Lee J. M. RSC Adv. 2012, 2, 10564. doi: 10.1039/C2RA21772D
[22]
19 Tao G. H. ; He L. ; Liu W. S. ; Xu L. ; Xiong W. ; Wang T. ; Kou Y. Green Chem. 2006, 8, 639. doi: 10.1039/B600813E
[23]
20 Fukumoto K. ; Yoshizawa M. ; Ohno H. J. Am. Chem. Soc. 2005, 127, 2398. doi: 10.1021/ja043451i
[24]
21 Wei J. ; Chang C. ; Zhang Y. Y. ; Hou S. Y. ; Fang D. W. ; Guan W. J. Chem. Thermodyn. 2015, 90, 310. doi: 10.1016/j.jct.2015.04.029
[25]
22 Ma X. X. ; Wei J. ; Zhang Q. B. ; Tian F. ; Feng Y. Y. ; Guan W. Ind. Eng. Chem. Res. 2013, 52, 9490. doi: 10.1021/ie401130d
[26]
24 Lide D. R. Handbook of Chemistry and Physics, 82nd ed., CRC Press: Boca Raton, FL, USA 2001–2002.
[27]
25 Adamson A.W. Physical Chemistry of Surfaces; Wiley: New York, NY, USA 1976.
[28]
26 Tong J. ; Wang L. F. ; Liu D. L. ; Chen T. F. ; Tong J. ; Yang J. Z. J. Chem. Thermodyn. 2016, 97, 221. doi: 10.1016/j.jct.2016.01.009
[29]
29 Mountain B. W. ; Seward T. M. Geochim. Cosmochim. Acta 2003, 67, 3005. doi: 10.1016/S0016-703700303-X
