| Full text | |
| Author(s): |
Jora, Manazael Z.
[1]
;
de Souza, Renato N.
[1]
;
Barbosa, Thais M.
[2]
;
Tormena, Claudio F.
[2]
;
Sabadini, Edvaldo
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Campinas UNICAMP, Inst Chem, Phys Chem Dept, POB 6154, BR-13084862 Campinas, SP - Brazil
[2] Univ Campinas UNICAMP, Inst Chem, Organ Chem Dept, POB 6154, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Langmuir; v. 35, n. 52, p. 17046-17053, DEC 31 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
The energy released when tetradecyltrimethylammonium bromide (C(14)TAB) is combined with different derivatives of chlorobenzoates in an isothermal titration calorimeter (ITC) allows a direct evaluation of the spontaneity of the threading of the aromatic anions into the micellar palisade. The comparison between the enthalpimetric curves with the ones for viscosity of the solutions, hydrodynamic radii of the aggregates (dynamic light scattering experiments), and the fraction of aromatic anions incorporated (diffusion-ordered spectroscopy experiments) allows the establishment of the variations of enthalpy with formation, growth, and decrease of the wormlike micelles (WLMs). The formation of WLMs with C(14)TAB is very favored (very exothermic) for titrations of chlorobenzoate derivatives which present the chlorine atom in positions 3 or 4 of the aromatic ring. However, the aggregation is highly unfavorable if chlorine is at position 2 of chlorobenzoate. According to the results, the high potential of the ITC to determine critical concentrations and the energies associated with the aggregation of a cationic surfactant and aromatic anions for the formation of WLMs was demonstrated. (AU) | |
| FAPESP's process: | 15/25406-5 - Organizing matter: colloids formed by association of surfactants, polymers and nanoparticles |
| Grantee: | Watson Loh |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 15/08541-6 - Nuclear magnetic resonance spectroscopy: beyond molecular structure assignment |
| Grantee: | Claudio Francisco Tormena |
| Support Opportunities: | Research Projects - Thematic Grants |