Aggregation behavior of alkyl triphenyl phosphonium bromides in aprotic and protic ionic liquids

• Published in: Colloid and polymer science Vol. 291; no. 10; pp. 2375 - 2384
• Main Authors: Lu, Fei, Shi, Lijuan, Gu, Yingqiu, Yang, Xiujie, Zheng, Liqiang
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2013; Springer; Springer Nature B.V
• Subjects: Agglomeration; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Complex Fluids and Microfluidics; Exact sciences and technology; Food Science; General and physical chemistry; Nanotechnology and Microengineering; Original Contribution; Physical Chemistry; Polymer Sciences; Soft and Granular Matter; Surface physical chemistry; Surface-active agents: properties; Aggregation behavior; Aprotic; Alkyltriphenylphonium bromides; Protic; Ionic liquid; Solvent effect; Substituent effect; Imidazole derivatives; Chemical solution; Iminium compounds; Cationic surfactant; Temperature effect; Experimental study; Dimension spectrum; Protic solvent; Quaternary phosphonium compound; Micellar critical concentration; Ammonium compound; Micellar solution; Aprotic solvent
• ISSN: 0303-402X; 1435-1536
• DOI: 10.1007/s00396-013-2986-x

The aggregation behavior of alkyltriphenylphonium bromides, C n TPB ( n  = 12 and 14), has been investigated in two different room-temperature ionic liquids (ILs), the aprotic 1-butyl-3-metyllimidazolium tetrafluoroborate ([bmim][BF 4 ]), and the protic ethylammonium nitrate (EAN). The critical micelle concentration was determined by the surface tension measurements. The calculated thermodynamic parameters based on surface tension measurements at various temperatures indicate that the micellization for C n TPB in both aprotic [bmim][BF 4 ] and protic EAN is enthalpy-driven. But stronger solvophobic interactions presented between C n TPB and protic EAN than aprotic [bmim][BF 4 ]. 1 H NMR spectra were further conducted to reveal that ethylammonium cation can insert into the micelle while imidazole cation only locates among the head groups of C n TPB.